feat: add board interface with cards, columns and dialogs

YKanBan.Tests/Storage/AppData/AppConfigStoreTests.cs

@@ -21,9 +21,10 @@ public class AppConfigStoreTests
         Assert.AreEqual(AppConfig.CurrentFormatVersion, config.Version);
         Assert.AreEqual(AppConfig.DefaultLanguage, config.Language);
         Assert.AreEqual(ThemeOption.FollowSystem, config.Theme);
-        Assert.AreEqual(CardSortOption.Id, config.Sort.Card);
+        Assert.AreEqual(SortOption.IdAscending, config.Display.CardSort);
-        Assert.AreEqual(ColumnWidthPreset.Standard, config.ColumnWidth.Preset);
+        Assert.AreEqual(SortOption.IdAscending, config.Display.ColumnSort);
-        Assert.AreEqual(320, config.ColumnWidth.CustomPixels);
+        Assert.AreEqual(ColumnWidthPreset.Standard, config.Display.ColumnWidth.Preset);
+        Assert.AreEqual(320, config.Display.ColumnWidth.CustomPixels);
         Assert.IsTrue(config.Confirmations.DeleteCard);
         Assert.IsTrue(config.Confirmations.DeleteColumn);
         Assert.IsTrue(config.Confirmations.DeleteTag);
@@ -66,8 +67,11 @@ public class AppConfigStoreTests
               "version": {{AppConfig.CurrentFormatVersion}},
               "language": "zh-Hans",
               "theme": "dark",
-              "sort": { "card": "title" },
+              "display": {
-              "column-width": { "preset": "custom", "custom-pixels": 400 },
+                "column-width": { "preset": "custom", "custom-pixels": 400 },
+                "card-sort": "title-asc",
+                "column-sort": "id-desc"
+              },
               "confirmations": {
                 "delete-card": false,
                 "delete-column": false,
@@ -82,9 +86,10 @@ public class AppConfigStoreTests
 
         Assert.AreEqual("zh-Hans", config.Language);
         Assert.AreEqual(ThemeOption.Dark, config.Theme);
-        Assert.AreEqual(CardSortOption.Title, config.Sort.Card);
+        Assert.AreEqual(SortOption.TitleAscending, config.Display.CardSort);
-        Assert.AreEqual(ColumnWidthPreset.Custom, config.ColumnWidth.Preset);
+        Assert.AreEqual(SortOption.IdDescending, config.Display.ColumnSort);
-        Assert.AreEqual(400, config.ColumnWidth.CustomPixels);
+        Assert.AreEqual(ColumnWidthPreset.Custom, config.Display.ColumnWidth.Preset);
+        Assert.AreEqual(400, config.Display.ColumnWidth.CustomPixels);
         Assert.IsFalse(config.Confirmations.DeleteCard);
         Assert.IsFalse(config.Confirmations.DeleteColumn);
         Assert.IsFalse(config.Confirmations.DeleteTag);
@@ -101,10 +106,10 @@ public class AppConfigStoreTests
 
         AppConfig config = store.Load();
 
-        Assert.IsNotNull(config.Sort);
+        Assert.IsNotNull(config.Display);
-        Assert.IsNotNull(config.ColumnWidth);
+        Assert.IsNotNull(config.Display.ColumnWidth);
         Assert.IsNotNull(config.Confirmations);
-        Assert.AreEqual(ColumnWidthPreset.Standard, config.ColumnWidth.Preset);
+        Assert.AreEqual(ColumnWidthPreset.Standard, config.Display.ColumnWidth.Preset);
     }
 
     [TestMethod]
@@ -117,8 +122,12 @@ public class AppConfigStoreTests
         var config = new AppConfig
         {
             Theme = ThemeOption.FollowSystem,
-            Sort = new SortSettings { Card = CardSortOption.UpdatedAt },
+            Display = new DisplaySettings
-            ColumnWidth = new ColumnWidthSettings { Preset = ColumnWidthPreset.Custom, CustomPixels = 500 },
+            {
+                CardSort = SortOption.UpdatedDescending,
+                ColumnSort = SortOption.CreatedAscending,
+                ColumnWidth = new ColumnWidthSettings { Preset = ColumnWidthPreset.Custom, CustomPixels = 500 },
+            },
             Confirmations = new ConfirmationSettings { DeleteColumn = false },
         };
         store.Save(config);
@@ -126,9 +135,12 @@ public class AppConfigStoreTests
         string json = File.ReadAllText(path);
         StringAssert.Contains(json, "\"delete-column\"");
         StringAssert.Contains(json, "\"discard-edit\"");
+        StringAssert.Contains(json, "\"card-sort\"");
+        StringAssert.Contains(json, "\"column-sort\"");
         StringAssert.Contains(json, "\"custom-pixels\"");
         StringAssert.Contains(json, "\"follow-system\"");
-        StringAssert.Contains(json, "\"updated-at\"");
+        StringAssert.Contains(json, "\"updated-desc\"");
+        StringAssert.Contains(json, "\"created-asc\"");
         // No member-name CamelCase must leak into the file.
         Assert.IsFalse(json.Contains("deleteColumn", StringComparison.Ordinal));
         Assert.IsFalse(json.Contains("CustomPixels", StringComparison.Ordinal));
@@ -145,8 +157,12 @@ public class AppConfigStoreTests
         {
             Language = "zh-Hans",
             Theme = ThemeOption.Light,
-            Sort = new SortSettings { Card = CardSortOption.CreatedAt },
+            Display = new DisplaySettings
-            ColumnWidth = new ColumnWidthSettings { Preset = ColumnWidthPreset.Wide },
+            {
+                CardSort = SortOption.CreatedDescending,
+                ColumnSort = SortOption.TitleAscending,
+                ColumnWidth = new ColumnWidthSettings { Preset = ColumnWidthPreset.Wide },
+            },
             Confirmations = new ConfirmationSettings { DiscardEdit = false },
         };
         store.Save(config);
@@ -154,8 +170,9 @@ public class AppConfigStoreTests
         AppConfig reloaded = store.Load();
         Assert.AreEqual(config.Language, reloaded.Language);
         Assert.AreEqual(config.Theme, reloaded.Theme);
-        Assert.AreEqual(config.Sort.Card, reloaded.Sort.Card);
+        Assert.AreEqual(config.Display.CardSort, reloaded.Display.CardSort);
-        Assert.AreEqual(config.ColumnWidth.Preset, reloaded.ColumnWidth.Preset);
+        Assert.AreEqual(config.Display.ColumnSort, reloaded.Display.ColumnSort);
+        Assert.AreEqual(config.Display.ColumnWidth.Preset, reloaded.Display.ColumnWidth.Preset);
         Assert.AreEqual(config.Confirmations.DiscardEdit, reloaded.Confirmations.DiscardEdit);
     }
 }

YKanBan.Tests/Storage/Workspace/WorkspacePresetTests.cs

@@ -6,34 +6,43 @@ using YKanBan.Tests.TestUtilities;
 namespace YKanBan.Tests.Storage.Workspace;
 
 /// <summary>
-/// Verifies that the preset column titles follow the UI language active when
+/// Verifies that the preset columns and tags follow the UI language active when
-/// they are added and then live as ordinary data. These tests mutate the
+/// they are added and then live as ordinary data. These tests mutate the global
-/// global <see cref="Resources.Culture"/>, so they are marked do-not-parallelize.
+/// <see cref="Resources.Culture"/>, so they are marked do-not-parallelize.
 /// </summary>
 [TestClass]
 [DoNotParallelize]
 public class WorkspacePresetTests
 {
     [TestMethod]
-    public void AddPresetColumnsStoresEnglishTitlesUnderEnglishCulture()
+    public void AddPresetColumnsStoresEnglishTextUnderEnglishCulture()
     {
         CultureInfo? original = Resources.Culture;
         try
         {
             Resources.Culture = new CultureInfo("en");
-            string[] expected =
-            [
-                Resources.PresetColumn_Todo,
-                Resources.PresetColumn_InProgress,
-                Resources.PresetColumn_Done,
-            ];
 
             using var directory = new TempDirectory();
             WorkspaceInitializer.Initialize(directory.FullPath);
             WorkspacePreset.AddPresetColumns(directory.FullPath);
 
             using SqliteConnection connection = SqliteTestHelper.OpenWorkspace(directory.FullPath);
-            CollectionAssert.AreEqual(expected, SqliteTestHelper.GetColumnTitles(connection));
+            CollectionAssert.AreEqual(
+                new[]
+                {
+                    Resources.PresetColumn_Todo,
+                    Resources.PresetColumn_InProgress,
+                    Resources.PresetColumn_Done,
+                },
+                SqliteTestHelper.GetColumnTitles(connection));
+            CollectionAssert.AreEqual(
+                new[]
+                {
+                    Resources.PresetColumn_Todo_Description,
+                    Resources.PresetColumn_InProgress_Description,
+                    Resources.PresetColumn_Done_Description,
+                },
+                SqliteTestHelper.GetColumnDescriptions(connection));
         }
         finally
         {
@@ -42,25 +51,29 @@ public class WorkspacePresetTests
     }
 
     [TestMethod]
-    public void AddPresetColumnsStoresChineseTitlesUnderChineseCulture()
+    public void AddPresetColumnsStoresChineseTextUnderChineseCulture()
     {
         CultureInfo? original = Resources.Culture;
         try
         {
             Resources.Culture = new CultureInfo("zh-Hans");
-            string[] expected =
-            [
-                Resources.PresetColumn_Todo,
-                Resources.PresetColumn_InProgress,
-                Resources.PresetColumn_Done,
-            ];
 
             using var directory = new TempDirectory();
             WorkspaceInitializer.Initialize(directory.FullPath);
             WorkspacePreset.AddPresetColumns(directory.FullPath);
 
             using SqliteConnection connection = SqliteTestHelper.OpenWorkspace(directory.FullPath);
-            CollectionAssert.AreEqual(expected, SqliteTestHelper.GetColumnTitles(connection));
+            CollectionAssert.AreEqual(
+                new[]
+                {
+                    Resources.PresetColumn_Todo,
+                    Resources.PresetColumn_InProgress,
+                    Resources.PresetColumn_Done,
+                },
+                SqliteTestHelper.GetColumnTitles(connection));
+            // Chinese resources must resolve to different text than English.
+            Assert.AreEqual("待办", Resources.PresetColumn_Todo);
+            Assert.AreEqual("已完成的任务。", Resources.PresetColumn_Done_Description);
         }
         finally
         {
@@ -69,27 +82,74 @@ public class WorkspacePresetTests
     }
 
     [TestMethod]
-    public void PresetTitlesAreDataAndIgnoreLaterCultureChanges()
+    public void AddPresetTagsStoresEightTagsUnderEnglishCulture()
+    {
+        CultureInfo? original = Resources.Culture;
+        try
+        {
+            Resources.Culture = new CultureInfo("en");
+
+            using var directory = new TempDirectory();
+            WorkspaceInitializer.Initialize(directory.FullPath);
+            WorkspacePreset.AddPresetTags(directory.FullPath);
+
+            using SqliteConnection connection = SqliteTestHelper.OpenWorkspace(directory.FullPath);
+            List<(string Name, string Color, string Description)> tags = SqliteTestHelper.GetTags(connection);
+
+            Assert.AreEqual(8, tags.Count);
+            Assert.AreEqual(("bug", "#d73a4a", "Something isn't working"), tags[0]);
+            Assert.AreEqual(("documentation", "#0075ca", "Improvements or additions to documentation"), tags[1]);
+            Assert.AreEqual(("wontfix", "#ffffff", "This will not be worked on"), tags[7]);
+        }
+        finally
+        {
+            Resources.Culture = original;
+        }
+    }
+
+    [TestMethod]
+    public void AddPresetTagsStoresChineseNamesUnderChineseCulture()
+    {
+        CultureInfo? original = Resources.Culture;
+        try
+        {
+            Resources.Culture = new CultureInfo("zh-Hans");
+
+            using var directory = new TempDirectory();
+            WorkspaceInitializer.Initialize(directory.FullPath);
+            WorkspacePreset.AddPresetTags(directory.FullPath);
+
+            using SqliteConnection connection = SqliteTestHelper.OpenWorkspace(directory.FullPath);
+            List<(string Name, string Color, string Description)> tags = SqliteTestHelper.GetTags(connection);
+
+            Assert.AreEqual(8, tags.Count);
+            Assert.AreEqual("缺陷", tags[0].Name);
+            Assert.AreEqual("功能没有正常工作", tags[0].Description);
+        }
+        finally
+        {
+            Resources.Culture = original;
+        }
+    }
+
+    [TestMethod]
+    public void PresetContentIsDataAndIgnoresLaterCultureChanges()
     {
         CultureInfo? original = Resources.Culture;
         try
         {
             Resources.Culture = new CultureInfo("en");
-            string[] expected =
-            [
-                Resources.PresetColumn_Todo,
-                Resources.PresetColumn_InProgress,
-                Resources.PresetColumn_Done,
-            ];
 
             using var directory = new TempDirectory();
             WorkspaceInitializer.Initialize(directory.FullPath);
             WorkspacePreset.AddPresetColumns(directory.FullPath);
+            WorkspacePreset.AddPresetTags(directory.FullPath);
 
             // Switching the language after adding the presets must not rewrite stored data.
             Resources.Culture = new CultureInfo("zh-Hans");
             using SqliteConnection connection = SqliteTestHelper.OpenWorkspace(directory.FullPath);
-            CollectionAssert.AreEqual(expected, SqliteTestHelper.GetColumnTitles(connection));
+            Assert.AreEqual("To Do", SqliteTestHelper.GetColumnTitles(connection)[0]);
+            Assert.AreEqual("bug", SqliteTestHelper.GetTags(connection)[0].Name);
         }
         finally
         {

YKanBan.Tests/TestUtilities/SqliteTestHelper.cs

@@ -87,6 +87,44 @@ public static class SqliteTestHelper
         return titles;
     }
 
+    /// <summary>
+    /// Returns the descriptions of all columns, ordered by id ascending.
+    /// </summary>
+    /// <param name="connection">An open database connection.</param>
+    /// <returns>The column descriptions in id order.</returns>
+    public static List<string> GetColumnDescriptions(SqliteConnection connection)
+    {
+        using var command = connection.CreateCommand();
+        command.CommandText = "SELECT description FROM columns ORDER BY id ASC;";
+        using var reader = command.ExecuteReader();
+
+        var descriptions = new List<string>();
+        while (reader.Read())
+        {
+            descriptions.Add(reader.GetString(0));
+        }
+        return descriptions;
+    }
+
+    /// <summary>
+    /// Returns all tags as name/color/description tuples, ordered by id ascending.
+    /// </summary>
+    /// <param name="connection">An open database connection.</param>
+    /// <returns>The tags in id order.</returns>
+    public static List<(string Name, string Color, string Description)> GetTags(SqliteConnection connection)
+    {
+        using var command = connection.CreateCommand();
+        command.CommandText = "SELECT name, color, description FROM tags ORDER BY id ASC;";
+        using var reader = command.ExecuteReader();
+
+        var tags = new List<(string, string, string)>();
+        while (reader.Read())
+        {
+            tags.Add((reader.GetString(0), reader.GetString(1), reader.GetString(2)));
+        }
+        return tags;
+    }
+
     /// <summary>
     /// Opens a workspace database with the real workspace migration list.
     /// </summary>

YKanBan/App.axaml

@@ -26,10 +26,20 @@
                 <ResourceDictionary x:Key="Light">
                     <SolidColorBrush x:Key="TopBarBackgroundBrush" Color="#F6F7F9"/>
                     <SolidColorBrush x:Key="TopBarBorderBrush" Color="#E2E4EA"/>
+                    <SolidColorBrush x:Key="BoardColumnBackgroundBrush" Color="#F1F2F5"/>
+                    <SolidColorBrush x:Key="BoardColumnBorderBrush" Color="#E2E4EA"/>
+                    <SolidColorBrush x:Key="CardBackgroundBrush" Color="#FFFFFF"/>
+                    <SolidColorBrush x:Key="CardBorderBrush" Color="#E2E4EA"/>
+                    <SolidColorBrush x:Key="ErrorTextBrush" Color="#C0392B"/>
                 </ResourceDictionary>
                 <ResourceDictionary x:Key="Dark">
                     <SolidColorBrush x:Key="TopBarBackgroundBrush" Color="#1C1E24"/>
                     <SolidColorBrush x:Key="TopBarBorderBrush" Color="#2C2F37"/>
+                    <SolidColorBrush x:Key="BoardColumnBackgroundBrush" Color="#17181C"/>
+                    <SolidColorBrush x:Key="BoardColumnBorderBrush" Color="#2C2F37"/>
+                    <SolidColorBrush x:Key="CardBackgroundBrush" Color="#23252B"/>
+                    <SolidColorBrush x:Key="CardBorderBrush" Color="#33363F"/>
+                    <SolidColorBrush x:Key="ErrorTextBrush" Color="#FF6B6B"/>
                 </ResourceDictionary>
             </ResourceDictionary.ThemeDictionaries>
         </ResourceDictionary>

YKanBan/Assets/Locales/Resources.resx

@@ -25,6 +25,9 @@
   <data name="Common_Cancel" xml:space="preserve">
     <value>Cancel</value>
   </data>
+  <data name="Common_Delete" xml:space="preserve">
+    <value>Delete</value>
+  </data>
   <data name="Main_Export" xml:space="preserve">
     <value>Export</value>
   </data>
@@ -40,6 +43,171 @@
   <data name="Tab_Board" xml:space="preserve">
     <value>Board</value>
   </data>
+  <data name="Board_SearchPlaceholder" xml:space="preserve">
+    <value>Search…</value>
+  </data>
+  <data name="Board_Search" xml:space="preserve">
+    <value>Search</value>
+  </data>
+  <data name="Board_ClearSearch" xml:space="preserve">
+    <value>Clear</value>
+  </data>
+  <data name="Board_AddColumn" xml:space="preserve">
+    <value>Add Column</value>
+  </data>
+  <data name="Board_ColumnWidth" xml:space="preserve">
+    <value>Column Width</value>
+  </data>
+  <data name="Board_SortCard" xml:space="preserve">
+    <value>Card Sort</value>
+  </data>
+  <data name="Board_SortColumn" xml:space="preserve">
+    <value>Column Sort</value>
+  </data>
+  <data name="Board_Display" xml:space="preserve">
+    <value>Display</value>
+  </data>
+  <data name="Board_NoColumns" xml:space="preserve">
+    <value>No columns yet.</value>
+  </data>
+  <data name="Sort_IdAsc" xml:space="preserve">
+    <value>ID Ascending</value>
+  </data>
+  <data name="Sort_IdDesc" xml:space="preserve">
+    <value>ID Descending</value>
+  </data>
+  <data name="Sort_CreatedAsc" xml:space="preserve">
+    <value>Created Ascending</value>
+  </data>
+  <data name="Sort_CreatedDesc" xml:space="preserve">
+    <value>Created Descending</value>
+  </data>
+  <data name="Sort_UpdatedAsc" xml:space="preserve">
+    <value>Modified Ascending</value>
+  </data>
+  <data name="Sort_UpdatedDesc" xml:space="preserve">
+    <value>Modified Descending</value>
+  </data>
+  <data name="Sort_TitleAsc" xml:space="preserve">
+    <value>Title Ascending</value>
+  </data>
+  <data name="Sort_TitleDesc" xml:space="preserve">
+    <value>Title Descending</value>
+  </data>
+  <data name="Column_AddCard" xml:space="preserve">
+    <value>New Card</value>
+  </data>
+  <data name="Column_Edit" xml:space="preserve">
+    <value>Edit</value>
+  </data>
+  <data name="Column_Delete" xml:space="preserve">
+    <value>Delete</value>
+  </data>
+  <data name="Card_Delete" xml:space="preserve">
+    <value>Delete</value>
+  </data>
+  <data name="Card_Move" xml:space="preserve">
+    <value>Move to Column…</value>
+  </data>
+  <data name="ColumnDialog_AddTitle" xml:space="preserve">
+    <value>New Column</value>
+  </data>
+  <data name="ColumnDialog_EditTitle" xml:space="preserve">
+    <value>Edit Column</value>
+  </data>
+  <data name="ColumnDialog_Title" xml:space="preserve">
+    <value>Title</value>
+  </data>
+  <data name="ColumnDialog_Description" xml:space="preserve">
+    <value>Description</value>
+  </data>
+  <data name="ColumnDialog_InvalidTitle" xml:space="preserve">
+    <value>The title is empty or already used.</value>
+  </data>
+  <data name="CardDialog_AddTitle" xml:space="preserve">
+    <value>New Card</value>
+  </data>
+  <data name="CardDialog_EditTitle" xml:space="preserve">
+    <value>Edit Card</value>
+  </data>
+  <data name="CardDialog_Title" xml:space="preserve">
+    <value>Title</value>
+  </data>
+  <data name="CardDialog_Content" xml:space="preserve">
+    <value>Content</value>
+  </data>
+  <data name="CardDialog_Tags" xml:space="preserve">
+    <value>Tags</value>
+  </data>
+  <data name="CardDialog_AddTag" xml:space="preserve">
+    <value>Add Tag</value>
+  </data>
+  <data name="CardDialog_Id" xml:space="preserve">
+    <value>ID: {0}</value>
+  </data>
+  <data name="CardDialog_Created" xml:space="preserve">
+    <value>Created: {0}</value>
+  </data>
+  <data name="CardDialog_Modified" xml:space="preserve">
+    <value>Modified: {0}</value>
+  </data>
+  <data name="CardDialog_TimePattern" xml:space="preserve">
+    <value>yyyy-MM-dd HH:mm</value>
+  </data>
+  <data name="CardDialog_Error" xml:space="preserve">
+    <value>Could not save the card.</value>
+  </data>
+  <data name="TagDialog_Title" xml:space="preserve">
+    <value>Add Tag</value>
+  </data>
+  <data name="TagDialog_Target" xml:space="preserve">
+    <value>Tag</value>
+  </data>
+  <data name="TagDialog_NoTargets" xml:space="preserve">
+    <value>There are no more tags to add.</value>
+  </data>
+  <data name="MoveDialog_Title" xml:space="preserve">
+    <value>Move Card</value>
+  </data>
+  <data name="MoveDialog_Target" xml:space="preserve">
+    <value>Target Column</value>
+  </data>
+  <data name="MoveDialog_NoTargets" xml:space="preserve">
+    <value>There is nowhere to move this card.</value>
+  </data>
+  <data name="WidthPreset_Narrow" xml:space="preserve">
+    <value>Narrow</value>
+  </data>
+  <data name="WidthPreset_Standard" xml:space="preserve">
+    <value>Standard</value>
+  </data>
+  <data name="WidthPreset_Wide" xml:space="preserve">
+    <value>Wide</value>
+  </data>
+  <data name="WidthPreset_Custom" xml:space="preserve">
+    <value>Custom</value>
+  </data>
+  <data name="WidthDialog_Pixels" xml:space="preserve">
+    <value>Pixels (160–720)</value>
+  </data>
+  <data name="Confirm_DeleteColumn_Title" xml:space="preserve">
+    <value>Delete Column</value>
+  </data>
+  <data name="Confirm_DeleteColumn_Message" xml:space="preserve">
+    <value>Delete column "{0}" and its {1} card(s)?</value>
+  </data>
+  <data name="Confirm_DeleteCard_Title" xml:space="preserve">
+    <value>Delete Card</value>
+  </data>
+  <data name="Confirm_DeleteCard_Message" xml:space="preserve">
+    <value>Delete card #{0}?</value>
+  </data>
+  <data name="Confirm_Discard_Title" xml:space="preserve">
+    <value>Discard Changes</value>
+  </data>
+  <data name="Confirm_Discard_Message" xml:space="preserve">
+    <value>Discard the unsaved changes?</value>
+  </data>
   <data name="Error_Argument_Title" xml:space="preserve">
     <value>Invalid arguments</value>
   </data>
@@ -62,7 +230,7 @@
     <value>The folder does not contain a .ykanban workspace: {0}</value>
   </data>
   <data name="Error_NotInitialized_Initialize" xml:space="preserve">
-    <value>Initialize workspace</value>
+    <value>Initialize Workspace</value>
   </data>
   <data name="Error_LockConflict_Title" xml:space="preserve">
     <value>Workspace locked</value>
@@ -95,7 +263,7 @@
     <value>Dark</value>
   </data>
   <data name="Settings_ThemeFollowSystem" xml:space="preserve">
-    <value>Follow system</value>
+    <value>Follow System</value>
   </data>
   <data name="Settings_Confirmations" xml:space="preserve">
     <value>Confirmations</value>
@@ -130,12 +298,69 @@
   <data name="PresetColumn_Todo" xml:space="preserve">
     <value>To Do</value>
   </data>
+  <data name="PresetColumn_Todo_Description" xml:space="preserve">
+    <value>Tasks that are planned but not started.</value>
+  </data>
   <data name="PresetColumn_InProgress" xml:space="preserve">
     <value>In Progress</value>
   </data>
+  <data name="PresetColumn_InProgress_Description" xml:space="preserve">
+    <value>Tasks that are currently being worked on.</value>
+  </data>
   <data name="PresetColumn_Done" xml:space="preserve">
     <value>Done</value>
   </data>
+  <data name="PresetColumn_Done_Description" xml:space="preserve">
+    <value>Tasks that have been completed.</value>
+  </data>
+  <data name="PresetTag_Bug_Name" xml:space="preserve">
+    <value>bug</value>
+  </data>
+  <data name="PresetTag_Bug_Description" xml:space="preserve">
+    <value>Something isn't working</value>
+  </data>
+  <data name="PresetTag_Documentation_Name" xml:space="preserve">
+    <value>documentation</value>
+  </data>
+  <data name="PresetTag_Documentation_Description" xml:space="preserve">
+    <value>Improvements or additions to documentation</value>
+  </data>
+  <data name="PresetTag_Duplicate_Name" xml:space="preserve">
+    <value>duplicate</value>
+  </data>
+  <data name="PresetTag_Duplicate_Description" xml:space="preserve">
+    <value>This issue or pull request already exists</value>
+  </data>
+  <data name="PresetTag_Enhancement_Name" xml:space="preserve">
+    <value>enhancement</value>
+  </data>
+  <data name="PresetTag_Enhancement_Description" xml:space="preserve">
+    <value>New feature or request</value>
+  </data>
+  <data name="PresetTag_HelpWanted_Name" xml:space="preserve">
+    <value>help-wanted</value>
+  </data>
+  <data name="PresetTag_HelpWanted_Description" xml:space="preserve">
+    <value>Extra attention is needed</value>
+  </data>
+  <data name="PresetTag_Invalid_Name" xml:space="preserve">
+    <value>invalid</value>
+  </data>
+  <data name="PresetTag_Invalid_Description" xml:space="preserve">
+    <value>This doesn't seem right</value>
+  </data>
+  <data name="PresetTag_Question_Name" xml:space="preserve">
+    <value>question</value>
+  </data>
+  <data name="PresetTag_Question_Description" xml:space="preserve">
+    <value>Further information is requested</value>
+  </data>
+  <data name="PresetTag_Wontfix_Name" xml:space="preserve">
+    <value>wontfix</value>
+  </data>
+  <data name="PresetTag_Wontfix_Description" xml:space="preserve">
+    <value>This will not be worked on</value>
+  </data>
   <data name="Export_FileNamePattern" xml:space="preserve">
     <value>{0}-export-{1:yyyyMMdd-HHmmss}.md</value>
   </data>

YKanBan/Assets/Locales/Resources.zh-Hans.resx

@@ -25,6 +25,9 @@
   <data name="Common_Cancel" xml:space="preserve">
     <value>取消</value>
   </data>
+  <data name="Common_Delete" xml:space="preserve">
+    <value>删除</value>
+  </data>
   <data name="Main_Export" xml:space="preserve">
     <value>导出</value>
   </data>
@@ -40,6 +43,171 @@
   <data name="Tab_Board" xml:space="preserve">
     <value>看板</value>
   </data>
+  <data name="Board_SearchPlaceholder" xml:space="preserve">
+    <value>搜索…</value>
+  </data>
+  <data name="Board_Search" xml:space="preserve">
+    <value>搜索</value>
+  </data>
+  <data name="Board_ClearSearch" xml:space="preserve">
+    <value>清空</value>
+  </data>
+  <data name="Board_AddColumn" xml:space="preserve">
+    <value>新增列</value>
+  </data>
+  <data name="Board_ColumnWidth" xml:space="preserve">
+    <value>列宽</value>
+  </data>
+  <data name="Board_SortCard" xml:space="preserve">
+    <value>卡片排序</value>
+  </data>
+  <data name="Board_SortColumn" xml:space="preserve">
+    <value>列排序</value>
+  </data>
+  <data name="Board_Display" xml:space="preserve">
+    <value>显示</value>
+  </data>
+  <data name="Board_NoColumns" xml:space="preserve">
+    <value>还没有列。</value>
+  </data>
+  <data name="Sort_IdAsc" xml:space="preserve">
+    <value>ID 正序</value>
+  </data>
+  <data name="Sort_IdDesc" xml:space="preserve">
+    <value>ID 倒序</value>
+  </data>
+  <data name="Sort_CreatedAsc" xml:space="preserve">
+    <value>创建时间正序</value>
+  </data>
+  <data name="Sort_CreatedDesc" xml:space="preserve">
+    <value>创建时间倒序</value>
+  </data>
+  <data name="Sort_UpdatedAsc" xml:space="preserve">
+    <value>修改时间正序</value>
+  </data>
+  <data name="Sort_UpdatedDesc" xml:space="preserve">
+    <value>修改时间倒序</value>
+  </data>
+  <data name="Sort_TitleAsc" xml:space="preserve">
+    <value>标题正序</value>
+  </data>
+  <data name="Sort_TitleDesc" xml:space="preserve">
+    <value>标题倒序</value>
+  </data>
+  <data name="Column_AddCard" xml:space="preserve">
+    <value>新建卡片</value>
+  </data>
+  <data name="Column_Edit" xml:space="preserve">
+    <value>编辑</value>
+  </data>
+  <data name="Column_Delete" xml:space="preserve">
+    <value>删除</value>
+  </data>
+  <data name="Card_Delete" xml:space="preserve">
+    <value>删除</value>
+  </data>
+  <data name="Card_Move" xml:space="preserve">
+    <value>移动到列…</value>
+  </data>
+  <data name="ColumnDialog_AddTitle" xml:space="preserve">
+    <value>新增列</value>
+  </data>
+  <data name="ColumnDialog_EditTitle" xml:space="preserve">
+    <value>编辑列</value>
+  </data>
+  <data name="ColumnDialog_Title" xml:space="preserve">
+    <value>标题</value>
+  </data>
+  <data name="ColumnDialog_Description" xml:space="preserve">
+    <value>描述</value>
+  </data>
+  <data name="ColumnDialog_InvalidTitle" xml:space="preserve">
+    <value>标题为空或已被使用。</value>
+  </data>
+  <data name="CardDialog_AddTitle" xml:space="preserve">
+    <value>新增卡片</value>
+  </data>
+  <data name="CardDialog_EditTitle" xml:space="preserve">
+    <value>编辑卡片</value>
+  </data>
+  <data name="CardDialog_Title" xml:space="preserve">
+    <value>标题</value>
+  </data>
+  <data name="CardDialog_Content" xml:space="preserve">
+    <value>内容</value>
+  </data>
+  <data name="CardDialog_Tags" xml:space="preserve">
+    <value>标签</value>
+  </data>
+  <data name="CardDialog_AddTag" xml:space="preserve">
+    <value>添加标签</value>
+  </data>
+  <data name="CardDialog_Id" xml:space="preserve">
+    <value>编号：{0}</value>
+  </data>
+  <data name="CardDialog_Created" xml:space="preserve">
+    <value>创建：{0}</value>
+  </data>
+  <data name="CardDialog_Modified" xml:space="preserve">
+    <value>修改：{0}</value>
+  </data>
+  <data name="CardDialog_TimePattern" xml:space="preserve">
+    <value>yyyy年M月d日 HH:mm</value>
+  </data>
+  <data name="CardDialog_Error" xml:space="preserve">
+    <value>无法保存卡片。</value>
+  </data>
+  <data name="TagDialog_Title" xml:space="preserve">
+    <value>添加标签</value>
+  </data>
+  <data name="TagDialog_Target" xml:space="preserve">
+    <value>标签</value>
+  </data>
+  <data name="TagDialog_NoTargets" xml:space="preserve">
+    <value>没有可添加的标签。</value>
+  </data>
+  <data name="MoveDialog_Title" xml:space="preserve">
+    <value>移动卡片</value>
+  </data>
+  <data name="MoveDialog_Target" xml:space="preserve">
+    <value>目标列</value>
+  </data>
+  <data name="MoveDialog_NoTargets" xml:space="preserve">
+    <value>没有可移动到的目标列。</value>
+  </data>
+  <data name="WidthPreset_Narrow" xml:space="preserve">
+    <value>窄</value>
+  </data>
+  <data name="WidthPreset_Standard" xml:space="preserve">
+    <value>标准</value>
+  </data>
+  <data name="WidthPreset_Wide" xml:space="preserve">
+    <value>宽</value>
+  </data>
+  <data name="WidthPreset_Custom" xml:space="preserve">
+    <value>自定义</value>
+  </data>
+  <data name="WidthDialog_Pixels" xml:space="preserve">
+    <value>像素（160–720）</value>
+  </data>
+  <data name="Confirm_DeleteColumn_Title" xml:space="preserve">
+    <value>删除列</value>
+  </data>
+  <data name="Confirm_DeleteColumn_Message" xml:space="preserve">
+    <value>删除列“{0}”及其 {1} 张卡片？</value>
+  </data>
+  <data name="Confirm_DeleteCard_Title" xml:space="preserve">
+    <value>删除卡片</value>
+  </data>
+  <data name="Confirm_DeleteCard_Message" xml:space="preserve">
+    <value>删除卡片 #{0}？</value>
+  </data>
+  <data name="Confirm_Discard_Title" xml:space="preserve">
+    <value>放弃修改</value>
+  </data>
+  <data name="Confirm_Discard_Message" xml:space="preserve">
+    <value>放弃未保存的修改？</value>
+  </data>
   <data name="Error_Argument_Title" xml:space="preserve">
     <value>参数错误</value>
   </data>
@@ -130,12 +298,69 @@
   <data name="PresetColumn_Todo" xml:space="preserve">
     <value>待办</value>
   </data>
+  <data name="PresetColumn_Todo_Description" xml:space="preserve">
+    <value>已计划但尚未开始的任务。</value>
+  </data>
   <data name="PresetColumn_InProgress" xml:space="preserve">
     <value>进行中</value>
   </data>
+  <data name="PresetColumn_InProgress_Description" xml:space="preserve">
+    <value>正在处理中的任务。</value>
+  </data>
   <data name="PresetColumn_Done" xml:space="preserve">
     <value>已完成</value>
   </data>
+  <data name="PresetColumn_Done_Description" xml:space="preserve">
+    <value>已完成的任务。</value>
+  </data>
+  <data name="PresetTag_Bug_Name" xml:space="preserve">
+    <value>缺陷</value>
+  </data>
+  <data name="PresetTag_Bug_Description" xml:space="preserve">
+    <value>功能没有正常工作</value>
+  </data>
+  <data name="PresetTag_Documentation_Name" xml:space="preserve">
+    <value>文档</value>
+  </data>
+  <data name="PresetTag_Documentation_Description" xml:space="preserve">
+    <value>文档的改进或补充</value>
+  </data>
+  <data name="PresetTag_Duplicate_Name" xml:space="preserve">
+    <value>重复</value>
+  </data>
+  <data name="PresetTag_Duplicate_Description" xml:space="preserve">
+    <value>该问题或请求已存在</value>
+  </data>
+  <data name="PresetTag_Enhancement_Name" xml:space="preserve">
+    <value>增强</value>
+  </data>
+  <data name="PresetTag_Enhancement_Description" xml:space="preserve">
+    <value>新功能或请求</value>
+  </data>
+  <data name="PresetTag_HelpWanted_Name" xml:space="preserve">
+    <value>需要帮助</value>
+  </data>
+  <data name="PresetTag_HelpWanted_Description" xml:space="preserve">
+    <value>需要额外关注</value>
+  </data>
+  <data name="PresetTag_Invalid_Name" xml:space="preserve">
+    <value>无效</value>
+  </data>
+  <data name="PresetTag_Invalid_Description" xml:space="preserve">
+    <value>似乎不正确</value>
+  </data>
+  <data name="PresetTag_Question_Name" xml:space="preserve">
+    <value>疑问</value>
+  </data>
+  <data name="PresetTag_Question_Description" xml:space="preserve">
+    <value>需要进一步信息</value>
+  </data>
+  <data name="PresetTag_Wontfix_Name" xml:space="preserve">
+    <value>不予处理</value>
+  </data>
+  <data name="PresetTag_Wontfix_Description" xml:space="preserve">
+    <value>不会被处理</value>
+  </data>
   <data name="Export_FileNamePattern" xml:space="preserve">
     <value>{0}-导出-{1:yyyyMMdd-HHmmss}.md</value>
   </data>

YKanBan/Storage/AppData/AppConfig.cs

@@ -4,26 +4,42 @@ using Newtonsoft.Json;
 namespace YKanBan.Storage.AppData;
 
 /// <summary>
-/// Card ordering options. Every order falls back to id ascending as the final
+/// Display ordering options, used for both cards and columns. Except for the id
-/// tie-breaker.
+/// order, every option falls back to id ascending as the final tie-breaker.
 /// </summary>
-public enum CardSortOption
+public enum SortOption
 {
-    /// <summary>Primary key ascending (default).</summary>
+    /// <summary>Primary key ascending.</summary>
-    [EnumMember(Value = "id")]
+    [EnumMember(Value = "id-asc")]
-    Id,
+    IdAscending,
 
-    /// <summary>Creation time, oldest first.</summary>
+    /// <summary>Primary key descending.</summary>
-    [EnumMember(Value = "created-at")]
+    [EnumMember(Value = "id-desc")]
-    CreatedAt,
+    IdDescending,
 
-    /// <summary>Last modification time, most recently modified first.</summary>
+    /// <summary>Creation time ascending.</summary>
-    [EnumMember(Value = "updated-at")]
+    [EnumMember(Value = "created-asc")]
-    UpdatedAt,
+    CreatedAscending,
 
-    /// <summary>Title by code points (BINARY collation); empty titles sort first.</summary>
+    /// <summary>Creation time descending.</summary>
-    [EnumMember(Value = "title")]
+    [EnumMember(Value = "created-desc")]
-    Title,
+    CreatedDescending,
+
+    /// <summary>Last modification time ascending.</summary>
+    [EnumMember(Value = "updated-asc")]
+    UpdatedAscending,
+
+    /// <summary>Last modification time descending.</summary>
+    [EnumMember(Value = "updated-desc")]
+    UpdatedDescending,
+
+    /// <summary>Title by code points (BINARY collation) ascending.</summary>
+    [EnumMember(Value = "title-asc")]
+    TitleAscending,
+
+    /// <summary>Title by code points (BINARY collation) descending.</summary>
+    [EnumMember(Value = "title-desc")]
+    TitleDescending,
 }
 
 /// <summary>
@@ -66,18 +82,6 @@ public enum ThemeOption
     FollowSystem,
 }
 
-/// <summary>
-/// Card ordering settings. The chosen order is global, not per workspace.
-/// </summary>
-public sealed class SortSettings
-{
-    /// <summary>
-    /// Gets or sets the order used by the board.
-    /// </summary>
-    [JsonProperty("card")]
-    public CardSortOption Card { get; set; } = CardSortOption.Id;
-}
-
 /// <summary>
 /// Board column width settings, applied globally.
 /// </summary>
@@ -97,6 +101,31 @@ public sealed class ColumnWidthSettings
     public int CustomPixels { get; set; } = 320;
 }
 
+/// <summary>
+/// Everything that controls how the board is displayed: the column width and
+/// the card and column ordering.
+/// </summary>
+public sealed class DisplaySettings
+{
+    /// <summary>
+    /// Gets or sets the board column width settings.
+    /// </summary>
+    [JsonProperty("column-width")]
+    public ColumnWidthSettings ColumnWidth { get; set; } = new();
+
+    /// <summary>
+    /// Gets or sets the order of cards within their column.
+    /// </summary>
+    [JsonProperty("card-sort")]
+    public SortOption CardSort { get; set; } = SortOption.IdAscending;
+
+    /// <summary>
+    /// Gets or sets the left-to-right order of the columns.
+    /// </summary>
+    [JsonProperty("column-sort")]
+    public SortOption ColumnSort { get; set; } = SortOption.IdAscending;
+}
+
 /// <summary>
 /// Confirmation-dialog toggles for the destructive actions.
 /// </summary>
@@ -164,16 +193,10 @@ public sealed class AppConfig
     public ThemeOption Theme { get; set; } = ThemeOption.FollowSystem;
 
     /// <summary>
-    /// Gets or sets the card ordering settings.
+    /// Gets or sets the board display settings (width and ordering).
     /// </summary>
-    [JsonProperty("sort")]
+    [JsonProperty("display")]
-    public SortSettings Sort { get; set; } = new();
+    public DisplaySettings Display { get; set; } = new();
-
-    /// <summary>
-    /// Gets or sets the board column width settings.
-    /// </summary>
-    [JsonProperty("column-width")]
-    public ColumnWidthSettings ColumnWidth { get; set; } = new();
 
     /// <summary>
     /// Gets or sets the confirmation-dialog settings.

YKanBan/Storage/AppData/AppConfigStore.cs

@@ -56,8 +56,7 @@ public sealed class AppConfigStore
             }
 
             // Older or hand-edited files may miss whole sections; each falls back to its defaults.
-            config.Sort ??= new SortSettings();
+            config.Display ??= new DisplaySettings();
-            config.ColumnWidth ??= new ColumnWidthSettings();
             config.Confirmations ??= new ConfirmationSettings();
             return config;
         }

YKanBan/Storage/Workspace/WorkspacePreset.cs

@@ -3,16 +3,16 @@ using Microsoft.Data.Sqlite;
 namespace YKanBan.Storage.Workspace;
 
 /// <summary>
-/// Adds the initial workspace content. The three preset column titles are read
+/// Adds the initial workspace content. The preset column titles/descriptions and
-/// straight from the ResX resources in the UI language active when they are
+/// tag names/descriptions are read straight from the ResX resources in the UI
-/// added; they then become ordinary data that no longer follows language
+/// language active when they are added; they then become ordinary data that no
-/// switches.
+/// longer follows language switches.
 /// </summary>
 public static class WorkspacePreset
 {
     /// <summary>
     /// Inserts the three preset columns (the current language's equivalents of
-    /// To Do / In Progress / Done) in a single transaction.
+    /// To Do / In Progress / Done) with their descriptions in a single transaction.
     /// </summary>
     /// <param name="folderPath">The initialized workspace folder.</param>
     /// <exception cref="SqliteException">The workspace database does not exist or a title collides with an existing column.</exception>
@@ -23,28 +23,70 @@ public static class WorkspacePreset
 
         long now = UnixTime.Now;
 
-        // Preset titles are data at creation time: whatever the current language says gets stored.
+        // Preset titles and descriptions are data at creation time: whatever the current language says gets stored.
-        string[] titles =
+        (string Title, string Description)[] columns =
         [
-            Resources.PresetColumn_Todo,
+            (Resources.PresetColumn_Todo, Resources.PresetColumn_Todo_Description),
-            Resources.PresetColumn_InProgress,
+            (Resources.PresetColumn_InProgress, Resources.PresetColumn_InProgress_Description),
-            Resources.PresetColumn_Done,
+            (Resources.PresetColumn_Done, Resources.PresetColumn_Done_Description),
         ];
 
         // Insert all three atomically so a partially populated workspace can never exist.
         using var transaction = connection.BeginTransaction();
-        foreach (string title in titles)
+        foreach ((string title, string description) in columns)
         {
             using var command = connection.CreateCommand();
             command.Transaction = transaction;
             command.CommandText = """
                 INSERT INTO columns (title, description, created_at, updated_at)
-                VALUES ($title, '', $now, $now);
+                VALUES ($title, $description, $now, $now);
                 """;
             command.Parameters.AddWithValue("$title", title);
+            command.Parameters.AddWithValue("$description", description);
             command.Parameters.AddWithValue("$now", now);
             command.ExecuteNonQuery();
         }
         transaction.Commit();
     }
+
+    /// <summary>
+    /// Inserts the preset tag set (names, colors and descriptions in the current
+    /// language) in a single transaction.
+    /// </summary>
+    /// <param name="folderPath">The initialized workspace folder.</param>
+    /// <exception cref="SqliteException">The workspace database does not exist or a tag name collides.</exception>
+    public static void AddPresetTags(string folderPath)
+    {
+        using SqliteConnection connection = SqliteDatabase.Open(
+            WorkspacePaths.Database(folderPath), WorkspaceSchema.Migrations);
+
+        // Colors are stored in the canonical lowercase #rrggbb form.
+        (string Name, string Color, string Description)[] tags =
+        [
+            (Resources.PresetTag_Bug_Name, "#d73a4a", Resources.PresetTag_Bug_Description),
+            (Resources.PresetTag_Documentation_Name, "#0075ca", Resources.PresetTag_Documentation_Description),
+            (Resources.PresetTag_Duplicate_Name, "#cfd3d7", Resources.PresetTag_Duplicate_Description),
+            (Resources.PresetTag_Enhancement_Name, "#a2eeef", Resources.PresetTag_Enhancement_Description),
+            (Resources.PresetTag_HelpWanted_Name, "#008672", Resources.PresetTag_HelpWanted_Description),
+            (Resources.PresetTag_Invalid_Name, "#e4e669", Resources.PresetTag_Invalid_Description),
+            (Resources.PresetTag_Question_Name, "#d876e3", Resources.PresetTag_Question_Description),
+            (Resources.PresetTag_Wontfix_Name, "#ffffff", Resources.PresetTag_Wontfix_Description),
+        ];
+
+        using var transaction = connection.BeginTransaction();
+        foreach ((string name, string color, string description) in tags)
+        {
+            using var command = connection.CreateCommand();
+            command.Transaction = transaction;
+            command.CommandText = """
+                INSERT INTO tags (name, color, description)
+                VALUES ($name, $color, $description);
+                """;
+            command.Parameters.AddWithValue("$name", name);
+            command.Parameters.AddWithValue("$color", color);
+            command.Parameters.AddWithValue("$description", description);
+            command.ExecuteNonQuery();
+        }
+        transaction.Commit();
+    }
 }

YKanBan/ViewModels/Board/BoardViewModel.cs

@@ -0,0 +1,271 @@
+using System.Collections.ObjectModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using YKanBan.Models;
+using YKanBan.Services;
+using YKanBan.Storage.AppData;
+using YKanBan.Storage.Workspace;
+
+namespace YKanBan.ViewModels.Board;
+
+/// <summary>
+/// The board tab: a toolbar (search box, add-column and the Display button)
+/// over horizontally arranged columns of vertically stacked cards. All
+/// persistence goes through the workspace repository; the board reloads from it
+/// after each change.
+/// </summary>
+public sealed partial class BoardViewModel : ViewModelBase
+{
+    private readonly AppServices _services;
+    private readonly WorkspaceRepository _repository;
+
+    /// <summary>
+    /// Initializes the board, loading its current content.
+    /// </summary>
+    /// <param name="services">The process composition root (configuration access).</param>
+    /// <param name="session">The open workspace session.</param>
+    public BoardViewModel(AppServices services, WorkspaceSession session)
+    {
+        _services = services;
+        _repository = session.Repository;
+        Display = new DisplaySettingsViewModel(_services.Config, Reload);
+
+        Reload();
+    }
+
+    /// <summary>
+    /// Gets the workspace repository used for all board data access.
+    /// </summary>
+    public WorkspaceRepository Repository => _repository;
+
+    /// <summary>
+    /// Gets the live application configuration.
+    /// </summary>
+    public AppConfig Config => _services.Config;
+
+    /// <summary>
+    /// Gets the display options (column width, card sort, column sort).
+    /// </summary>
+    public DisplaySettingsViewModel Display { get; }
+
+    /// <summary>
+    /// Gets the columns shown by the board, in display order.
+    /// </summary>
+    public ObservableCollection<ColumnViewModel> Columns { get; } = [];
+
+    /// <summary>
+    /// Gets or sets the search box text. The board does not filter on change;
+    /// the search runs only when the search button is used.
+    /// </summary>
+    [ObservableProperty]
+    private string searchText = string.Empty;
+
+    /// <summary>
+    /// Gets the rendered column width in pixels, applied globally.
+    /// </summary>
+    [ObservableProperty]
+    private double columnWidth;
+
+    /// <summary>
+    /// Gets a value indicating whether the board has any columns.
+    /// </summary>
+    public bool HasColumns => Columns.Count > 0;
+
+    /// <summary>
+    /// Gets a value indicating whether the board is empty.
+    /// </summary>
+    public bool HasNoColumns => Columns.Count == 0;
+
+    #region Interactions
+
+    /// <summary>Gets the interaction that opens the new-column editor.</summary>
+    public Interaction<Unit> AddColumn { get; } = new();
+
+    /// <summary>Gets the interaction that opens the column editor.</summary>
+    public Interaction<ColumnViewModel> EditColumn { get; } = new();
+
+    /// <summary>Gets the interaction that confirms and deletes a column.</summary>
+    public Interaction<ColumnViewModel> DeleteColumn { get; } = new();
+
+    /// <summary>Gets the interaction that opens the new-card editor.</summary>
+    public Interaction<ColumnViewModel> AddCard { get; } = new();
+
+    /// <summary>Gets the interaction that opens the card editor.</summary>
+    public Interaction<CardViewModel> EditCard { get; } = new();
+
+    /// <summary>Gets the interaction that confirms and deletes a card.</summary>
+    public Interaction<CardViewModel> DeleteCard { get; } = new();
+
+    /// <summary>Gets the interaction that opens the move-card dialog.</summary>
+    public Interaction<CardViewModel> MoveCard { get; } = new();
+
+    /// <summary>Gets the interaction that runs the current search.</summary>
+    public Interaction<Unit> RunSearch { get; } = new();
+
+    #endregion
+
+    #region Commands
+
+    /// <summary>
+    /// Opens the new-column editor.
+    /// </summary>
+    [RelayCommand]
+    private Task AddNewColumnAsync() => AddColumn.Handle(Unit.Value);
+
+    /// <summary>
+    /// Runs the current search (wired up with the search feature).
+    /// </summary>
+    [RelayCommand]
+    private Task SearchAsync() => RunSearch.Handle(Unit.Value);
+
+    /// <summary>
+    /// Clears the search box.
+    /// </summary>
+    [RelayCommand]
+    private void ClearSearch() => SearchText = string.Empty;
+
+    #endregion
+
+    #region Requests from columns and cards
+
+    /// <summary>
+    /// Requests the new-card editor for the given column.
+    /// </summary>
+    /// <param name="column">The target column.</param>
+    /// <returns>A task completing after the editor closes.</returns>
+    public Task RequestAddCardAsync(ColumnViewModel column) => AddCard.Handle(column);
+
+    /// <summary>
+    /// Requests the editor for the given card.
+    /// </summary>
+    /// <param name="card">The card to edit.</param>
+    /// <returns>A task completing after the editor closes.</returns>
+    public Task RequestEditCardAsync(CardViewModel card) => EditCard.Handle(card);
+
+    /// <summary>
+    /// Requests deletion of the given card.
+    /// </summary>
+    /// <param name="card">The card to delete.</param>
+    /// <returns>A task completing after confirmation.</returns>
+    public Task RequestDeleteCardAsync(CardViewModel card) => DeleteCard.Handle(card);
+
+    /// <summary>
+    /// Requests moving the given card to another column.
+    /// </summary>
+    /// <param name="card">The card to move.</param>
+    /// <returns>A task completing after the move.</returns>
+    public Task RequestMoveCardAsync(CardViewModel card) => MoveCard.Handle(card);
+
+    /// <summary>
+    /// Requests the editor for the given column.
+    /// </summary>
+    /// <param name="column">The column to edit.</param>
+    /// <returns>A task completing after the editor closes.</returns>
+    public Task RequestEditColumnAsync(ColumnViewModel column) => EditColumn.Handle(column);
+
+    /// <summary>
+    /// Requests deletion of the given column.
+    /// </summary>
+    /// <param name="column">The column to delete.</param>
+    /// <returns>A task completing after confirmation.</returns>
+    public Task RequestDeleteColumnAsync(ColumnViewModel column) => DeleteColumn.Handle(column);
+
+    #endregion
+
+    #region Loading and ordering
+
+    /// <summary>
+    /// Reloads all columns and cards from the repository and rebuilds the board.
+    /// </summary>
+    public void Reload()
+    {
+        IReadOnlyList<ColumnModel> columns = _repository.GetColumns();
+        IReadOnlyList<CardModel> cards = _repository.GetCards();
+
+        // Group cards by column once so each column can be built independently.
+        Dictionary<long, List<CardModel>> cardsByColumn = cards
+            .GroupBy(card => card.ColumnId)
+            .ToDictionary(group => group.Key, group => group.ToList());
+
+        IEnumerable<ColumnModel> orderedColumns = SortColumns(columns, _services.Config.Display.ColumnSort);
+
+        Columns.Clear();
+        foreach (ColumnModel column in orderedColumns)
+        {
+            // Cards are sorted within their column by the selected card order.
+            IEnumerable<CardModel> columnCards = cardsByColumn.TryGetValue(column.Id, out List<CardModel>? list)
+                ? SortCards(list, _services.Config.Display.CardSort)
+                : [];
+            Columns.Add(new ColumnViewModel(this, column, columnCards.Select(card => new CardViewModel(this, card))));
+        }
+
+        ApplyColumnWidth();
+        OnPropertyChanged(nameof(HasColumns));
+        OnPropertyChanged(nameof(HasNoColumns));
+    }
+
+    /// <summary>
+    /// Recomputes the global column width and pushes it to every column.
+    /// </summary>
+    public void ApplyColumnWidth()
+    {
+        ColumnWidth = ColumnWidthPixels(_services.Config.Display.ColumnWidth);
+        foreach (ColumnViewModel column in Columns)
+        {
+            column.Width = ColumnWidth;
+        }
+    }
+
+    /// <summary>
+    /// Resolves a column width setting to its pixel value.
+    /// </summary>
+    /// <param name="settings">The configured column width.</param>
+    /// <returns>The width in pixels.</returns>
+    public static double ColumnWidthPixels(ColumnWidthSettings settings) => settings.Preset switch
+    {
+        ColumnWidthPreset.Narrow => 240,
+        ColumnWidthPreset.Wide => 480,
+        ColumnWidthPreset.Custom => settings.CustomPixels,
+        _ => 320,
+    };
+
+    /// <summary>
+    /// Orders cards by the selected option, tie-breaking by id ascending.
+    /// </summary>
+    /// <param name="cards">The cards to order.</param>
+    /// <param name="option">The selected order.</param>
+    /// <returns>The ordered cards.</returns>
+    private static IEnumerable<CardModel> SortCards(IEnumerable<CardModel> cards, SortOption option) => option switch
+    {
+        SortOption.IdAscending => cards.OrderBy(card => card.Id),
+        SortOption.IdDescending => cards.OrderByDescending(card => card.Id),
+        SortOption.CreatedAscending => cards.OrderBy(card => card.CreatedAt).ThenBy(card => card.Id),
+        SortOption.CreatedDescending => cards.OrderByDescending(card => card.CreatedAt).ThenBy(card => card.Id),
+        SortOption.UpdatedAscending => cards.OrderBy(card => card.UpdatedAt).ThenBy(card => card.Id),
+        SortOption.UpdatedDescending => cards.OrderByDescending(card => card.UpdatedAt).ThenBy(card => card.Id),
+        SortOption.TitleAscending => cards.OrderBy(card => card.Title, StringComparer.Ordinal).ThenBy(card => card.Id),
+        SortOption.TitleDescending => cards.OrderByDescending(card => card.Title, StringComparer.Ordinal).ThenBy(card => card.Id),
+        _ => cards.OrderBy(card => card.Id),
+    };
+
+    /// <summary>
+    /// Orders columns by the selected option, tie-breaking by id ascending.
+    /// </summary>
+    /// <param name="columns">The columns to order.</param>
+    /// <param name="option">The selected order.</param>
+    /// <returns>The ordered columns.</returns>
+    private static IEnumerable<ColumnModel> SortColumns(IEnumerable<ColumnModel> columns, SortOption option) => option switch
+    {
+        SortOption.IdAscending => columns.OrderBy(column => column.Id),
+        SortOption.IdDescending => columns.OrderByDescending(column => column.Id),
+        SortOption.CreatedAscending => columns.OrderBy(column => column.CreatedAt).ThenBy(column => column.Id),
+        SortOption.CreatedDescending => columns.OrderByDescending(column => column.CreatedAt).ThenBy(column => column.Id),
+        SortOption.UpdatedAscending => columns.OrderBy(column => column.UpdatedAt).ThenBy(column => column.Id),
+        SortOption.UpdatedDescending => columns.OrderByDescending(column => column.UpdatedAt).ThenBy(column => column.Id),
+        SortOption.TitleAscending => columns.OrderBy(column => column.Title, StringComparer.Ordinal).ThenBy(column => column.Id),
+        SortOption.TitleDescending => columns.OrderByDescending(column => column.Title, StringComparer.Ordinal).ThenBy(column => column.Id),
+        _ => columns.OrderBy(column => column.Id),
+    };
+
+    #endregion
+}

YKanBan/ViewModels/Board/CardViewModel.cs

@@ -0,0 +1,105 @@
+using CommunityToolkit.Mvvm.Input;
+using YKanBan.Models;
+
+namespace YKanBan.ViewModels.Board;
+
+/// <summary>
+/// One card on the board. Clicking the card body opens the editor; the corner
+/// menu offers delete and move. The shown text is the "#id title" heading, a
+/// truncated content preview and the colored tag badges; timestamps are not
+/// shown on the board.
+/// </summary>
+public sealed partial class CardViewModel : ViewModelBase
+{
+    /// <summary>Maximum number of content characters shown in the card preview.</summary>
+    private const int PreviewLength = 200;
+
+    private readonly BoardViewModel _board;
+
+    /// <summary>
+    /// Initializes the card view from its model.
+    /// </summary>
+    /// <param name="board">The owning board view model.</param>
+    /// <param name="card">The card model to display.</param>
+    public CardViewModel(BoardViewModel board, CardModel card)
+    {
+        _board = board;
+        Model = card;
+        TagBadges = card.Tags.Select(tag => new TagBadgeViewModel(tag)).ToList();
+    }
+
+    /// <summary>
+    /// Gets the underlying card model.
+    /// </summary>
+    public CardModel Model { get; }
+
+    /// <summary>
+    /// Gets the card id.
+    /// </summary>
+    public long Id => Model.Id;
+
+    /// <summary>
+    /// Gets the owning column id.
+    /// </summary>
+    public long ColumnId => Model.ColumnId;
+
+    /// <summary>
+    /// Gets the tag badges shown under the content.
+    /// </summary>
+    public IReadOnlyList<TagBadgeViewModel> TagBadges { get; }
+
+    /// <summary>
+    /// Gets the bold id marker, for example "#61".
+    /// </summary>
+    public string IdText => $"#{Model.Id}";
+
+    /// <summary>
+    /// Gets the card title, empty when the card has no title.
+    /// </summary>
+    public string TitleText => Model.Title;
+
+    /// <summary>
+    /// Gets a value indicating whether the card has a title to show.
+    /// </summary>
+    public bool HasTitle => Model.Title.Length > 0;
+
+    /// <summary>
+    /// Gets a value indicating whether the card has content to preview.
+    /// </summary>
+    public bool HasContent => Model.Content.Length > 0;
+
+    /// <summary>
+    /// Gets the content preview, collapsed to one line and truncated.
+    /// </summary>
+    public string PreviewContent
+    {
+        get
+        {
+            string singleLine = Model.Content.Replace("\r", " ").Replace("\n", " ");
+            return singleLine.Length <= PreviewLength ? singleLine : singleLine[..PreviewLength] + "…";
+        }
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether the card has any tags.
+    /// </summary>
+    public bool HasTags => TagBadges.Count > 0;
+
+    /// <summary>
+    /// Opens the card editor.
+    /// </summary>
+    [RelayCommand]
+    private void Edit() => _ = _board.RequestEditCardAsync(this);
+
+    /// <summary>
+    /// Asks the board to delete this card.
+    /// </summary>
+    [RelayCommand]
+    private void Delete() => _ = _board.RequestDeleteCardAsync(this);
+
+    /// <summary>
+    /// Asks the board to move this card to another column.
+    /// </summary>
+    [RelayCommand]
+    private void Move() => _ = _board.RequestMoveCardAsync(this);
+}

YKanBan/ViewModels/Board/ColumnViewModel.cs

@@ -0,0 +1,89 @@
+using System.Collections.ObjectModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using YKanBan.Models;
+
+namespace YKanBan.ViewModels.Board;
+
+/// <summary>
+/// One board column: a header with its title, card count and actions, plus the
+/// vertically stacked cards.
+/// </summary>
+public sealed partial class ColumnViewModel : ViewModelBase
+{
+    private readonly BoardViewModel _board;
+
+    /// <summary>
+    /// Initializes the column view from its model and cards.
+    /// </summary>
+    /// <param name="board">The owning board view model.</param>
+    /// <param name="column">The column model.</param>
+    /// <param name="cards">The already sorted cards belonging to this column.</param>
+    public ColumnViewModel(BoardViewModel board, ColumnModel column, IEnumerable<CardViewModel> cards)
+    {
+        _board = board;
+        Model = column;
+        Cards = new ObservableCollection<CardViewModel>(cards);
+        width = board.ColumnWidth;
+    }
+
+    /// <summary>
+    /// Gets the underlying column model.
+    /// </summary>
+    public ColumnModel Model { get; }
+
+    /// <summary>
+    /// Gets the column id.
+    /// </summary>
+    public long Id => Model.Id;
+
+    /// <summary>
+    /// Gets the column title.
+    /// </summary>
+    public string Title => Model.Title;
+
+    /// <summary>
+    /// Gets the column description.
+    /// </summary>
+    public string Description => Model.Description;
+
+    /// <summary>
+    /// Gets the cards in this column, already in display order.
+    /// </summary>
+    public ObservableCollection<CardViewModel> Cards { get; }
+
+    /// <summary>
+    /// Gets the number of cards in this column.
+    /// </summary>
+    public int CardCount => Cards.Count;
+
+    /// <summary>
+    /// Gets the tooltip text: the column description when present, otherwise
+    /// <see langword="null"/> so no tooltip is shown.
+    /// </summary>
+    public string? ToolTipText => Model.Description.Length > 0 ? Model.Description : null;
+
+    /// <summary>
+    /// Gets or sets the rendered column width in pixels, applied globally.
+    /// </summary>
+    [ObservableProperty]
+    private double width;
+
+    /// <summary>
+    /// Opens the editor for a new card in this column.
+    /// </summary>
+    [RelayCommand]
+    private void AddCard() => _ = _board.RequestAddCardAsync(this);
+
+    /// <summary>
+    /// Opens the editor for this column.
+    /// </summary>
+    [RelayCommand]
+    private void Edit() => _ = _board.RequestEditColumnAsync(this);
+
+    /// <summary>
+    /// Asks the board to delete this column.
+    /// </summary>
+    [RelayCommand]
+    private void Delete() => _ = _board.RequestDeleteColumnAsync(this);
+}

YKanBan/ViewModels/Board/DisplaySettingsViewModel.cs

@@ -0,0 +1,170 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using YKanBan.Storage.AppData;
+
+namespace YKanBan.ViewModels.Board;
+
+/// <summary>
+/// The board display options shown in the Display flyout: the global column
+/// width and the separate card and column orderings. Every change writes to
+/// the configuration and asks the board to refresh immediately.
+/// </summary>
+public sealed partial class DisplaySettingsViewModel : ViewModelBase
+{
+    /// <summary>Smallest accepted manual width.</summary>
+    public const int MinimumPixels = 160;
+
+    /// <summary>Largest accepted manual width.</summary>
+    public const int MaximumPixels = 720;
+
+    private readonly AppConfig _config;
+    private readonly Action _refresh;
+
+    /// <summary>
+    /// Initializes the display options from the configuration.
+    /// </summary>
+    /// <param name="config">The live application configuration.</param>
+    /// <param name="refresh">Invoked after every change to refresh the board.</param>
+    public DisplaySettingsViewModel(AppConfig config, Action refresh)
+    {
+        _config = config;
+        _refresh = refresh;
+
+        Presets =
+        [
+            new OptionItem(ColumnWidthPreset.Narrow, Resources.WidthPreset_Narrow),
+            new OptionItem(ColumnWidthPreset.Standard, Resources.WidthPreset_Standard),
+            new OptionItem(ColumnWidthPreset.Wide, Resources.WidthPreset_Wide),
+            new OptionItem(ColumnWidthPreset.Custom, Resources.WidthPreset_Custom),
+        ];
+        SortOptions = BuildSortOptions();
+
+        selectedPreset = Presets.FirstOrDefault(option => (ColumnWidthPreset)option.Value == config.Display.ColumnWidth.Preset)
+            ?? Presets[1];
+        customPixels = config.Display.ColumnWidth.CustomPixels;
+        selectedCardSort = FindSort(SortOptions, config.Display.CardSort);
+        selectedColumnSort = FindSort(SortOptions, config.Display.ColumnSort);
+    }
+
+    /// <summary>
+    /// Gets the width preset choices.
+    /// </summary>
+    public IReadOnlyList<OptionItem> Presets { get; }
+
+    /// <summary>
+    /// Gets the ordering choices (shared by cards and columns).
+    /// </summary>
+    public IReadOnlyList<OptionItem> SortOptions { get; }
+
+    /// <summary>
+    /// Gets or sets the selected width preset.
+    /// </summary>
+    [ObservableProperty]
+    private OptionItem? selectedPreset;
+
+    /// <summary>
+    /// Gets or sets the manual pixel width used by the custom preset.
+    /// </summary>
+    [ObservableProperty]
+    private decimal? customPixels;
+
+    /// <summary>
+    /// Gets or sets the selected card order.
+    /// </summary>
+    [ObservableProperty]
+    private OptionItem? selectedCardSort;
+
+    /// <summary>
+    /// Gets or sets the selected column order.
+    /// </summary>
+    [ObservableProperty]
+    private OptionItem? selectedColumnSort;
+
+    /// <summary>
+    /// Gets a value indicating whether the custom preset is selected.
+    /// </summary>
+    public bool IsCustom => SelectedPreset is not null && (ColumnWidthPreset)SelectedPreset.Value == ColumnWidthPreset.Custom;
+
+    /// <summary>
+    /// Stores the width preset and refreshes the board.
+    /// </summary>
+    /// <param name="value">The new selection.</param>
+    partial void OnSelectedPresetChanged(OptionItem? value)
+    {
+        OnPropertyChanged(nameof(IsCustom));
+        if (value is not null)
+        {
+            _config.Display.ColumnWidth.Preset = (ColumnWidthPreset)value.Value;
+            _refresh();
+        }
+    }
+
+    /// <summary>
+    /// Stores the manual width and refreshes the board when the custom preset is active.
+    /// </summary>
+    /// <param name="value">The new pixel count.</param>
+    partial void OnCustomPixelsChanged(decimal? value)
+    {
+        if (value is null)
+        {
+            return;
+        }
+
+        int pixels = (int)value.Value;
+        _config.Display.ColumnWidth.CustomPixels = pixels;
+        if (IsCustom)
+        {
+            _refresh();
+        }
+    }
+
+    /// <summary>
+    /// Stores the card order and refreshes the board.
+    /// </summary>
+    /// <param name="value">The new selection.</param>
+    partial void OnSelectedCardSortChanged(OptionItem? value)
+    {
+        if (value is not null)
+        {
+            _config.Display.CardSort = (SortOption)value.Value;
+            _refresh();
+        }
+    }
+
+    /// <summary>
+    /// Stores the column order and refreshes the board.
+    /// </summary>
+    /// <param name="value">The new selection.</param>
+    partial void OnSelectedColumnSortChanged(OptionItem? value)
+    {
+        if (value is not null)
+        {
+            _config.Display.ColumnSort = (SortOption)value.Value;
+            _refresh();
+        }
+    }
+
+    /// <summary>
+    /// Builds the localized eight-way ordering option list.
+    /// </summary>
+    /// <returns>The ordering options.</returns>
+    private static IReadOnlyList<OptionItem> BuildSortOptions() =>
+    [
+        new OptionItem(SortOption.IdAscending, Resources.Sort_IdAsc),
+        new OptionItem(SortOption.IdDescending, Resources.Sort_IdDesc),
+        new OptionItem(SortOption.CreatedAscending, Resources.Sort_CreatedAsc),
+        new OptionItem(SortOption.CreatedDescending, Resources.Sort_CreatedDesc),
+        new OptionItem(SortOption.UpdatedAscending, Resources.Sort_UpdatedAsc),
+        new OptionItem(SortOption.UpdatedDescending, Resources.Sort_UpdatedDesc),
+        new OptionItem(SortOption.TitleAscending, Resources.Sort_TitleAsc),
+        new OptionItem(SortOption.TitleDescending, Resources.Sort_TitleDesc),
+    ];
+
+    /// <summary>
+    /// Finds the option matching a stored sort value.
+    /// </summary>
+    /// <param name="options">The option list.</param>
+    /// <param name="value">The stored value.</param>
+    /// <returns>The matching option, or the first option.</returns>
+    private static OptionItem FindSort(IReadOnlyList<OptionItem> options, SortOption value) =>
+        options.FirstOrDefault(option => (SortOption)option.Value == value) ?? options[0];
+}

YKanBan/ViewModels/Board/TagBadgeViewModel.cs

@@ -0,0 +1,62 @@
+using Avalonia.Media;
+using YKanBan.Models;
+
+namespace YKanBan.ViewModels.Board;
+
+/// <summary>
+/// A read-only colored tag badge shown on a card: the tag name over a
+/// background taken directly from the tag color (user data, never themed) and
+/// an automatically contrasting text color.
+/// </summary>
+public sealed class TagBadgeViewModel
+{
+    /// <summary>
+    /// Initializes a badge from a tag.
+    /// </summary>
+    /// <param name="tag">The tag to render.</param>
+    public TagBadgeViewModel(TagModel tag)
+    {
+        Tag = tag;
+        Name = tag.Name;
+        Color background = Color.FromRgb(tag.Color.R, tag.Color.G, tag.Color.B);
+        Background = new SolidColorBrush(background);
+        Foreground = new SolidColorBrush(ContrastingTextColor(background));
+    }
+
+    /// <summary>
+    /// Gets the underlying tag model.
+    /// </summary>
+    public TagModel Tag { get; }
+
+    /// <summary>
+    /// Gets the tag name.
+    /// </summary>
+    public string Name { get; }
+
+    /// <summary>
+    /// Gets the tooltip text: the tag description when present, otherwise
+    /// <see langword="null"/> so no tooltip is shown.
+    /// </summary>
+    public string? ToolTipText => Tag.Description.Length > 0 ? Tag.Description : null;
+
+    /// <summary>
+    /// Gets the badge background brush.
+    /// </summary>
+    public IBrush Background { get; }
+
+    /// <summary>
+    /// Gets the badge text brush.
+    /// </summary>
+    public IBrush Foreground { get; }
+
+    /// <summary>
+    /// Picks black or white text for readability against the given background.
+    /// </summary>
+    /// <param name="background">The badge background color.</param>
+    /// <returns>The contrasting text color.</returns>
+    private static Color ContrastingTextColor(Color background)
+    {
+        double luminance = (0.299 * background.R + 0.587 * background.G + 0.114 * background.B) / 255.0;
+        return luminance > 0.6 ? Colors.Black : Colors.White;
+    }
+}

YKanBan/ViewModels/Dialogs/AssignedTagViewModel.cs

@@ -0,0 +1,55 @@
+using Avalonia.Media;
+using CommunityToolkit.Mvvm.Input;
+using YKanBan.Models;
+using YKanBan.ViewModels.Board;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// One tag assigned to the card being edited, shown with a colored badge and a
+/// remove action that only changes the in-memory assignment (the actual write
+/// happens on confirm).
+/// </summary>
+public sealed partial class AssignedTagViewModel
+{
+    private readonly CardEditorViewModel _editor;
+    private readonly TagBadgeViewModel _badge;
+
+    /// <summary>
+    /// Initializes the assigned-tag row.
+    /// </summary>
+    /// <param name="editor">The owning card editor.</param>
+    /// <param name="tag">The assigned tag.</param>
+    public AssignedTagViewModel(CardEditorViewModel editor, TagModel tag)
+    {
+        _editor = editor;
+        Tag = tag;
+        _badge = new TagBadgeViewModel(tag);
+    }
+
+    /// <summary>
+    /// Gets the assigned tag model.
+    /// </summary>
+    public TagModel Tag { get; }
+
+    /// <summary>
+    /// Gets the tag name.
+    /// </summary>
+    public string Name => _badge.Name;
+
+    /// <summary>
+    /// Gets the badge background brush.
+    /// </summary>
+    public IBrush Background => _badge.Background;
+
+    /// <summary>
+    /// Gets the badge text brush.
+    /// </summary>
+    public IBrush Foreground => _badge.Foreground;
+
+    /// <summary>
+    /// Removes this tag from the in-memory assignment.
+    /// </summary>
+    [RelayCommand]
+    private void Remove() => _editor.RemoveTag(Tag);
+}

YKanBan/ViewModels/Dialogs/CardEditorViewModel.cs

@@ -0,0 +1,196 @@
+using System.Collections.ObjectModel;
+using System.Globalization;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using Microsoft.Data.Sqlite;
+using YKanBan.Models;
+using YKanBan.Storage.Workspace;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The add/edit card dialog: title, content and the assigned-tag area, plus
+/// read-only id and timestamps for an existing card. The confirm writes the
+/// card and its tag assignment as one unit; a confirm with no effective change
+/// writes nothing; cancelling never writes.
+/// </summary>
+public sealed partial class CardEditorViewModel : ViewModelBase
+{
+    private readonly WorkspaceRepository _repository;
+    private readonly long _columnId;
+    private readonly CardModel? _existing;
+
+    /// <summary>
+    /// Initializes the dialog for a new or existing card.
+    /// </summary>
+    /// <param name="repository">The workspace repository.</param>
+    /// <param name="columnId">The owning column (used when adding).</param>
+    /// <param name="existing">The card to edit, or <see langword="null"/> to add one.</param>
+    public CardEditorViewModel(WorkspaceRepository repository, long columnId, CardModel? existing)
+    {
+        _repository = repository;
+        _columnId = columnId;
+        _existing = existing;
+        title = existing?.Title ?? string.Empty;
+        content = existing?.Content ?? string.Empty;
+        AssignedTags = new ObservableCollection<AssignedTagViewModel>(
+            (existing?.Tags ?? []).Select(tag => new AssignedTagViewModel(this, tag)));
+
+        if (existing is not null)
+        {
+            IdLine = string.Format(Culture, Resources.CardDialog_Id, $"#{existing.Id}");
+            CreatedLine = string.Format(Culture, Resources.CardDialog_Created, FormatTime(existing.CreatedAt));
+            ModifiedLine = string.Format(Culture, Resources.CardDialog_Modified, FormatTime(existing.UpdatedAt));
+        }
+    }
+
+    /// <summary>
+    /// Gets the interaction that opens the nested tag picker.
+    /// </summary>
+    public Interaction<Unit, TagModel?> ShowTagPicker { get; } = new();
+
+    /// <summary>
+    /// Gets the workspace repository (used by the tag picker).
+    /// </summary>
+    public WorkspaceRepository Repository => _repository;
+
+    /// <summary>
+    /// Gets a value indicating whether this dialog creates a new card.
+    /// </summary>
+    public bool IsNew => _existing is null;
+
+    /// <summary>
+    /// Gets the localized window title.
+    /// </summary>
+    public string WindowTitle => IsNew ? Resources.CardDialog_AddTitle : Resources.CardDialog_EditTitle;
+
+    /// <summary>
+    /// Gets the read-only id line, empty for a new card.
+    /// </summary>
+    public string IdLine { get; } = string.Empty;
+
+    /// <summary>
+    /// Gets the read-only created line, empty for a new card.
+    /// </summary>
+    public string CreatedLine { get; } = string.Empty;
+
+    /// <summary>
+    /// Gets the read-only modified line, empty for a new card.
+    /// </summary>
+    public string ModifiedLine { get; } = string.Empty;
+
+    /// <summary>
+    /// Gets the tags currently assigned to the card (in memory until confirmed).
+    /// </summary>
+    public ObservableCollection<AssignedTagViewModel> AssignedTags { get; }
+
+    /// <summary>
+    /// Gets or sets the card title.
+    /// </summary>
+    [ObservableProperty]
+    private string title;
+
+    /// <summary>
+    /// Gets or sets the card content.
+    /// </summary>
+    [ObservableProperty]
+    private string content;
+
+    /// <summary>
+    /// Gets or sets the inline error shown when the write fails.
+    /// </summary>
+    [ObservableProperty]
+    private string? errorMessage;
+
+    /// <summary>
+    /// Gets a value indicating whether there are unsaved effective changes.
+    /// </summary>
+    public bool HasChanges
+    {
+        get
+        {
+            if (_existing is null)
+            {
+                return Title.Length > 0 || Content.Length > 0 || AssignedTags.Count > 0;
+            }
+
+            bool tagsChanged = !AssignedTags.Select(row => row.Tag.Id).ToHashSet()
+                .SetEquals(_existing.Tags.Select(tag => tag.Id));
+            return _existing.Title != Title || _existing.Content != Content || tagsChanged;
+        }
+    }
+
+    /// <summary>
+    /// Opens the nested tag picker and adds the chosen tag when it is new to the card.
+    /// </summary>
+    [RelayCommand]
+    private async Task AddTagAsync()
+    {
+        TagModel? tag = await ShowTagPicker.Handle(Unit.Value);
+        if (tag is not null && AssignedTags.All(row => row.Tag.Id != tag.Id))
+        {
+            AssignedTags.Add(new AssignedTagViewModel(this, tag));
+        }
+    }
+
+    /// <summary>
+    /// Removes a tag from the in-memory assignment.
+    /// </summary>
+    /// <param name="tag">The tag to remove.</param>
+    public void RemoveTag(TagModel tag)
+    {
+        AssignedTagViewModel? row = AssignedTags.FirstOrDefault(item => item.Tag.Id == tag.Id);
+        if (row is not null)
+        {
+            AssignedTags.Remove(row);
+        }
+    }
+
+    /// <summary>
+    /// Writes the card and its tags when there is an effective change.
+    /// </summary>
+    /// <returns><see langword="true"/> when the dialog may close.</returns>
+    public bool TryAccept()
+    {
+        ErrorMessage = null;
+
+        // A confirm with no effective change writes nothing and just closes.
+        if (!HasChanges)
+        {
+            return true;
+        }
+
+        try
+        {
+            IReadOnlyCollection<long> tagIds = AssignedTags.Select(row => row.Tag.Id).ToList();
+            if (_existing is null)
+            {
+                _repository.AddCard(_columnId, Title, Content, tagIds);
+            }
+            else
+            {
+                _repository.UpdateCard(_existing.Id, Title, Content, tagIds);
+            }
+
+            return true;
+        }
+        catch (SqliteException)
+        {
+            ErrorMessage = Resources.CardDialog_Error;
+            return false;
+        }
+    }
+
+    /// <summary>
+    /// Gets the culture used for formatted read-only lines.
+    /// </summary>
+    private static CultureInfo Culture => Resources.Culture ?? CultureInfo.CurrentCulture;
+
+    /// <summary>
+    /// Formats a stored timestamp as a local time using the UI language pattern.
+    /// </summary>
+    /// <param name="unixSeconds">The stored timestamp.</param>
+    /// <returns>The formatted local time.</returns>
+    private static string FormatTime(long unixSeconds) =>
+        DateTimeOffset.FromUnixTimeSeconds(unixSeconds).ToLocalTime().ToString(Resources.CardDialog_TimePattern, Culture);
+}

YKanBan/ViewModels/Dialogs/ColumnEditorViewModel.cs

@@ -0,0 +1,85 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using Microsoft.Data.Sqlite;
+using YKanBan.Models;
+using YKanBan.Storage.Workspace;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The add/edit column dialog: a required title and an optional description.
+/// The write happens when the dialog is accepted; a duplicate or empty title
+/// keeps the dialog open with an inline error.
+/// </summary>
+public sealed partial class ColumnEditorViewModel : ViewModelBase
+{
+    private readonly WorkspaceRepository _repository;
+    private readonly ColumnModel? _existing;
+
+    /// <summary>
+    /// Initializes the dialog for a new or existing column.
+    /// </summary>
+    /// <param name="repository">The workspace repository.</param>
+    /// <param name="existing">The column to edit, or <see langword="null"/> to add one.</param>
+    public ColumnEditorViewModel(WorkspaceRepository repository, ColumnModel? existing)
+    {
+        _repository = repository;
+        _existing = existing;
+        title = existing?.Title ?? string.Empty;
+        description = existing?.Description ?? string.Empty;
+    }
+
+    /// <summary>
+    /// Gets a value indicating whether this dialog creates a new column.
+    /// </summary>
+    public bool IsNew => _existing is null;
+
+    /// <summary>
+    /// Gets the localized window title.
+    /// </summary>
+    public string WindowTitle => IsNew ? Resources.ColumnDialog_AddTitle : Resources.ColumnDialog_EditTitle;
+
+    /// <summary>
+    /// Gets or sets the column title.
+    /// </summary>
+    [ObservableProperty]
+    private string title;
+
+    /// <summary>
+    /// Gets or sets the column description.
+    /// </summary>
+    [ObservableProperty]
+    private string description;
+
+    /// <summary>
+    /// Gets or sets the inline error shown when the title is rejected.
+    /// </summary>
+    [ObservableProperty]
+    private string? errorMessage;
+
+    /// <summary>
+    /// Writes the column when accepted.
+    /// </summary>
+    /// <returns><see langword="true"/> when the dialog may close.</returns>
+    public bool TryAccept()
+    {
+        ErrorMessage = null;
+        try
+        {
+            if (_existing is null)
+            {
+                _repository.AddColumn(Title, Description);
+            }
+            else
+            {
+                _repository.UpdateColumn(_existing.Id, Title, Description);
+            }
+
+            return true;
+        }
+        catch (SqliteException)
+        {
+            ErrorMessage = Resources.ColumnDialog_InvalidTitle;
+            return false;
+        }
+    }
+}

YKanBan/ViewModels/Dialogs/DeleteCardConfirmViewModel.cs

@@ -0,0 +1,26 @@
+using System.Globalization;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The confirmation shown before deleting a card, naming the card id.
+/// </summary>
+public sealed class DeleteCardConfirmViewModel : ViewModelBase
+{
+    /// <summary>
+    /// Initializes the confirmation.
+    /// </summary>
+    /// <param name="cardId">The id of the card to delete.</param>
+    public DeleteCardConfirmViewModel(long cardId)
+    {
+        Message = string.Format(
+            Resources.Culture ?? CultureInfo.CurrentCulture,
+            Resources.Confirm_DeleteCard_Message,
+            cardId);
+    }
+
+    /// <summary>
+    /// Gets the localized confirmation message.
+    /// </summary>
+    public string Message { get; }
+}

YKanBan/ViewModels/Dialogs/DeleteColumnConfirmViewModel.cs

@@ -0,0 +1,29 @@
+using System.Globalization;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The confirmation shown before deleting a column, naming the column and how
+/// many cards it will cascade-delete.
+/// </summary>
+public sealed class DeleteColumnConfirmViewModel : ViewModelBase
+{
+    /// <summary>
+    /// Initializes the confirmation.
+    /// </summary>
+    /// <param name="columnTitle">The title of the column to delete.</param>
+    /// <param name="cardCount">The number of cards in the column.</param>
+    public DeleteColumnConfirmViewModel(string columnTitle, int cardCount)
+    {
+        Message = string.Format(
+            Resources.Culture ?? CultureInfo.CurrentCulture,
+            Resources.Confirm_DeleteColumn_Message,
+            columnTitle,
+            cardCount);
+    }
+
+    /// <summary>
+    /// Gets the localized confirmation message.
+    /// </summary>
+    public string Message { get; }
+}

YKanBan/ViewModels/Dialogs/DiscardEditConfirmViewModel.cs

@@ -0,0 +1,12 @@
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The confirmation shown before closing an editor with unsaved changes.
+/// </summary>
+public sealed class DiscardEditConfirmViewModel : ViewModelBase
+{
+    /// <summary>
+    /// Gets the localized confirmation message.
+    /// </summary>
+    public string Message => Resources.Confirm_Discard_Message;
+}

YKanBan/ViewModels/Dialogs/MoveCardViewModel.cs

@@ -0,0 +1,40 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using YKanBan.Models;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The move-card dialog: choose one of the other columns as the destination.
+/// </summary>
+public sealed partial class MoveCardViewModel : ViewModelBase
+{
+    /// <summary>
+    /// Initializes the dialog with the candidate destination columns.
+    /// </summary>
+    /// <param name="columns">All columns; the card's current column is excluded.</param>
+    /// <param name="currentColumnId">The card's current column id.</param>
+    public MoveCardViewModel(IReadOnlyList<ColumnModel> columns, long currentColumnId)
+    {
+        Targets = columns
+            .Where(column => column.Id != currentColumnId)
+            .Select(column => new OptionItem(column.Id, column.Title))
+            .ToList();
+        selectedTarget = Targets.FirstOrDefault();
+    }
+
+    /// <summary>
+    /// Gets the candidate destination columns.
+    /// </summary>
+    public IReadOnlyList<OptionItem> Targets { get; }
+
+    /// <summary>
+    /// Gets or sets the selected destination column.
+    /// </summary>
+    [ObservableProperty]
+    private OptionItem? selectedTarget;
+
+    /// <summary>
+    /// Gets a value indicating whether there is anywhere to move the card.
+    /// </summary>
+    public bool CanMove => Targets.Count > 0;
+}

YKanBan/ViewModels/Dialogs/TagPickerViewModel.cs

@@ -0,0 +1,43 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using YKanBan.Storage.Workspace;
+using YKanBan.ViewModels.Board;
+
+namespace YKanBan.ViewModels.Dialogs;
+
+/// <summary>
+/// The nested tag picker opened from the card editor: choose one tag that is
+/// not already assigned to the card. When no candidate remains the picker
+/// shows a message and cannot be confirmed.
+/// </summary>
+public sealed partial class TagPickerViewModel : ViewModelBase
+{
+    /// <summary>
+    /// Initializes the picker with the tags not yet assigned to the card.
+    /// </summary>
+    /// <param name="repository">The workspace repository.</param>
+    /// <param name="assignedTagIds">The tag ids already assigned to the card.</param>
+    public TagPickerViewModel(WorkspaceRepository repository, IReadOnlyCollection<long> assignedTagIds)
+    {
+        Targets = repository.GetTags()
+            .Where(tag => !assignedTagIds.Contains(tag.Id))
+            .Select(tag => new TagBadgeViewModel(tag))
+            .ToList();
+        selectedTarget = Targets.FirstOrDefault();
+    }
+
+    /// <summary>
+    /// Gets the assignable tags.
+    /// </summary>
+    public IReadOnlyList<TagBadgeViewModel> Targets { get; }
+
+    /// <summary>
+    /// Gets or sets the selected tag.
+    /// </summary>
+    [ObservableProperty]
+    private TagBadgeViewModel? selectedTarget;
+
+    /// <summary>
+    /// Gets a value indicating whether there is a tag to add.
+    /// </summary>
+    public bool CanAdd => Targets.Count > 0;
+}

YKanBan/ViewModels/MainWindowViewModel.cs

@@ -98,7 +98,7 @@ public sealed partial class MainWindowViewModel : ViewModelBase
     private void OpenWorkspace(string folderPath)
     {
         WorkspaceSession session = _services.OpenWorkspace(folderPath);
-        Content = new WorkspaceViewModel(session, ShowSettings, ShowAbout);
+        Content = new WorkspaceViewModel(_services, session, ShowSettings, ShowAbout);
         Title = $"{new DirectoryInfo(folderPath).Name} - {Resources.App_Name}";
     }
 
@@ -118,6 +118,7 @@ public sealed partial class MainWindowViewModel : ViewModelBase
         {
             WorkspaceInitializer.Initialize(page.FolderPath);
             WorkspacePreset.AddPresetColumns(page.FolderPath);
+            WorkspacePreset.AddPresetTags(page.FolderPath);
             OpenWorkspace(page.FolderPath);
         }
         catch (Exception exception) when (exception is YKanBanException or IOException or UnauthorizedAccessException)

YKanBan/ViewModels/WorkspaceViewModel.cs

@@ -1,12 +1,13 @@
 using CommunityToolkit.Mvvm.Input;
+using YKanBan.Services;
 using YKanBan.Storage.Workspace;
+using YKanBan.ViewModels.Board;
 
 namespace YKanBan.ViewModels;
 
 /// <summary>
 /// The normal workspace view: the top display area (name, path and the export,
-/// settings and about buttons) plus the tags/board tabs. The tab contents are
+/// settings and about buttons) plus the board and tags tabs.
-/// filled in by the board and tag features.
 /// </summary>
 public sealed partial class WorkspaceViewModel : ViewModelBase
 {
@@ -16,10 +17,12 @@ public sealed partial class WorkspaceViewModel : ViewModelBase
     /// <summary>
     /// Initializes the view for an open workspace.
     /// </summary>
+    /// <param name="services">The process composition root.</param>
     /// <param name="session">The open workspace session.</param>
     /// <param name="showSettings">The interaction that opens the settings dialog.</param>
     /// <param name="showAbout">The interaction that opens the about dialog.</param>
     public WorkspaceViewModel(
+        AppServices services,
         WorkspaceSession session,
         Interaction<Unit> showSettings,
         Interaction<Unit> showAbout)
@@ -29,6 +32,7 @@ public sealed partial class WorkspaceViewModel : ViewModelBase
         WorkspacePath = session.FolderPath;
         _showSettings = showSettings;
         _showAbout = showAbout;
+        Board = new BoardViewModel(services, session);
     }
 
     /// <summary>
@@ -46,6 +50,11 @@ public sealed partial class WorkspaceViewModel : ViewModelBase
     /// </summary>
     public string WorkspacePath { get; }
 
+    /// <summary>
+    /// Gets the board tab view model.
+    /// </summary>
+    public BoardViewModel Board { get; }
+
     /// <summary>
     /// Opens the settings dialog through the registered interaction.
     /// </summary>

YKanBan/Views/Board/BoardView.axaml

@@ -0,0 +1,114 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:vm="using:YKanBan.ViewModels.Board"
+             xmlns:vmBase="using:YKanBan.ViewModels"
+             xmlns:lang="using:YKanBan"
+             xmlns:icons="using:IconPacks.Avalonia.Lucide"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             mc:Ignorable="d" d:DesignWidth="1000" d:DesignHeight="600"
+             x:Class="YKanBan.Views.Board.BoardView"
+             x:DataType="vm:BoardViewModel">
+
+    <Grid RowDefinitions="Auto,*">
+
+        <!-- Toolbar: search, add column and the combined display options. -->
+        <Grid Grid.Row="0" Margin="8" ColumnDefinitions="*,Auto,Auto,Auto,Auto">
+            <TextBox Grid.Column="0" Text="{Binding SearchText}" VerticalAlignment="Center"
+                     Watermark="{x:Static lang:Resources.Board_SearchPlaceholder}"/>
+
+            <Button Grid.Column="1" Margin="4,0,0,0" Command="{Binding ClearSearchCommand}"
+                    ToolTip.Tip="{x:Static lang:Resources.Board_ClearSearch}">
+                <icons:PackIconLucide Kind="X" Width="16" Height="16"/>
+            </Button>
+
+            <Button Grid.Column="2" Margin="4,0,0,0" Command="{Binding SearchCommand}"
+                    ToolTip.Tip="{x:Static lang:Resources.Board_Search}">
+                <icons:PackIconLucide Kind="Search" Width="16" Height="16"/>
+            </Button>
+
+            <Button Grid.Column="3" Margin="12,0,0,0" Command="{Binding AddNewColumnCommand}">
+                <StackPanel Orientation="Horizontal" Spacing="6">
+                    <icons:PackIconLucide Kind="Plus" Width="16" Height="16"/>
+                    <TextBlock Text="{x:Static lang:Resources.Board_AddColumn}"/>
+                </StackPanel>
+            </Button>
+
+            <Button Grid.Column="4" Margin="4,0,0,0">
+                <StackPanel Orientation="Horizontal" Spacing="6">
+                    <icons:PackIconLucide Kind="SlidersHorizontal" Width="16" Height="16"/>
+                    <TextBlock Text="{x:Static lang:Resources.Board_Display}"/>
+                </StackPanel>
+                <Button.Flyout>
+                    <Flyout Placement="BottomEdgeAlignedRight">
+                        <StackPanel Width="280" Spacing="12" Margin="4">
+
+                            <StackPanel Spacing="4">
+                                <TextBlock Text="{x:Static lang:Resources.Board_ColumnWidth}"/>
+                                <ComboBox ItemsSource="{Binding Display.Presets}"
+                                          SelectedItem="{Binding Display.SelectedPreset}"
+                                          HorizontalAlignment="Stretch">
+                                    <ComboBox.ItemTemplate>
+                                        <DataTemplate x:DataType="vmBase:OptionItem">
+                                            <TextBlock Text="{Binding Label}"/>
+                                        </DataTemplate>
+                                    </ComboBox.ItemTemplate>
+                                </ComboBox>
+                                <StackPanel Orientation="Horizontal" Spacing="8"
+                                            IsVisible="{Binding Display.IsCustom}">
+                                    <TextBlock Text="{x:Static lang:Resources.WidthDialog_Pixels}"
+                                               VerticalAlignment="Center"/>
+                                    <NumericUpDown Value="{Binding Display.CustomPixels}"
+                                                   Minimum="160" Maximum="720" Width="120"/>
+                                </StackPanel>
+                            </StackPanel>
+
+                            <StackPanel Spacing="4">
+                                <TextBlock Text="{x:Static lang:Resources.Board_SortCard}"/>
+                                <ComboBox ItemsSource="{Binding Display.SortOptions}"
+                                          SelectedItem="{Binding Display.SelectedCardSort}"
+                                          HorizontalAlignment="Stretch">
+                                    <ComboBox.ItemTemplate>
+                                        <DataTemplate x:DataType="vmBase:OptionItem">
+                                            <TextBlock Text="{Binding Label}"/>
+                                        </DataTemplate>
+                                    </ComboBox.ItemTemplate>
+                                </ComboBox>
+                            </StackPanel>
+
+                            <StackPanel Spacing="4">
+                                <TextBlock Text="{x:Static lang:Resources.Board_SortColumn}"/>
+                                <ComboBox ItemsSource="{Binding Display.SortOptions}"
+                                          SelectedItem="{Binding Display.SelectedColumnSort}"
+                                          HorizontalAlignment="Stretch">
+                                    <ComboBox.ItemTemplate>
+                                        <DataTemplate x:DataType="vmBase:OptionItem">
+                                            <TextBlock Text="{Binding Label}"/>
+                                        </DataTemplate>
+                                    </ComboBox.ItemTemplate>
+                                </ComboBox>
+                            </StackPanel>
+
+                        </StackPanel>
+                    </Flyout>
+                </Button.Flyout>
+            </Button>
+        </Grid>
+
+        <!-- Board surface: columns horizontally, each scrolling its cards vertically. -->
+        <ScrollViewer Grid.Row="1" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled">
+            <ItemsControl ItemsSource="{Binding Columns}" Margin="8">
+                <ItemsControl.ItemsPanel>
+                    <ItemsPanelTemplate>
+                        <StackPanel Orientation="Horizontal" Spacing="12"/>
+                    </ItemsPanelTemplate>
+                </ItemsControl.ItemsPanel>
+            </ItemsControl>
+        </ScrollViewer>
+
+        <TextBlock Grid.Row="1" Text="{x:Static lang:Resources.Board_NoColumns}"
+                   IsVisible="{Binding HasNoColumns}"
+                   HorizontalAlignment="Center" VerticalAlignment="Center" Opacity="0.6"/>
+
+    </Grid>
+</UserControl>

YKanBan/Views/Board/BoardView.axaml.cs

@@ -0,0 +1,148 @@
+using Avalonia.Controls;
+using YKanBan.ViewModels.Board;
+using YKanBan.ViewModels.Dialogs;
+using YKanBan.Views.Dialogs;
+
+namespace YKanBan.Views.Board;
+
+public partial class BoardView : UserControl
+{
+    private bool _registered;
+
+    public BoardView()
+    {
+        InitializeComponent();
+    }
+
+    protected override void OnDataContextChanged(EventArgs e)
+    {
+        base.OnDataContextChanged(e);
+        if (DataContext is BoardViewModel board && !_registered)
+        {
+            _registered = true;
+            board.AddColumn.RegisterHandler(_ => EditColumnAsync(board, null));
+            board.EditColumn.RegisterHandler(column => EditColumnAsync(board, column));
+            board.DeleteColumn.RegisterHandler(column => DeleteColumnAsync(board, column));
+            board.AddCard.RegisterHandler(column => EditCardAsync(board, column, null));
+            board.EditCard.RegisterHandler(card => EditCardAsync(board, null, card));
+            board.DeleteCard.RegisterHandler(card => DeleteCardAsync(board, card));
+            board.MoveCard.RegisterHandler(card => MoveCardAsync(board, card));
+
+            // The search button is present in the shell; searching arrives with the search feature.
+            board.RunSearch.RegisterHandler(_ => Task.CompletedTask);
+        }
+    }
+
+    /// <summary>Gets the window that owns this board, used as the dialog owner.</summary>
+    private Window? OwningWindow => TopLevel.GetTopLevel(this) as Window;
+
+    /// <summary>Shows the add/edit column dialog and reloads on success.</summary>
+    private async Task EditColumnAsync(BoardViewModel board, ColumnViewModel? column)
+    {
+        if (OwningWindow is not Window owner)
+        {
+            return;
+        }
+
+        var dialog = new ColumnEditorDialog
+        {
+            DataContext = new ColumnEditorViewModel(board.Repository, column?.Model),
+        };
+        if (await dialog.ShowDialog<bool>(owner))
+        {
+            board.Reload();
+        }
+    }
+
+    /// <summary>Confirms and deletes a column, then reloads.</summary>
+    private async Task DeleteColumnAsync(BoardViewModel board, ColumnViewModel column)
+    {
+        if (OwningWindow is not Window owner)
+        {
+            return;
+        }
+
+        bool confirmed = true;
+        if (board.Config.Confirmations.DeleteColumn)
+        {
+            var dialog = new DeleteColumnConfirmDialog
+            {
+                DataContext = new DeleteColumnConfirmViewModel(column.Title, column.CardCount),
+            };
+            confirmed = await dialog.ShowDialog<bool>(owner);
+        }
+
+        if (!confirmed)
+        {
+            return;
+        }
+
+        board.Repository.DeleteColumn(column.Id);
+        board.Reload();
+    }
+
+    /// <summary>Shows the add/edit card dialog and reloads on success.</summary>
+    private async Task EditCardAsync(BoardViewModel board, ColumnViewModel? column, CardViewModel? card)
+    {
+        if (OwningWindow is not Window owner)
+        {
+            return;
+        }
+
+        long columnId = card?.ColumnId ?? column!.Id;
+        var dialog = new CardEditorDialog
+        {
+            DataContext = new CardEditorViewModel(board.Repository, columnId, card?.Model),
+        };
+        if (await dialog.ShowDialog<bool>(owner))
+        {
+            board.Reload();
+        }
+    }
+
+    /// <summary>Confirms and deletes a card, then reloads.</summary>
+    private async Task DeleteCardAsync(BoardViewModel board, CardViewModel card)
+    {
+        if (OwningWindow is not Window owner)
+        {
+            return;
+        }
+
+        bool confirmed = true;
+        if (board.Config.Confirmations.DeleteCard)
+        {
+            var dialog = new DeleteCardConfirmDialog
+            {
+                DataContext = new DeleteCardConfirmViewModel(card.Id),
+            };
+            confirmed = await dialog.ShowDialog<bool>(owner);
+        }
+
+        if (!confirmed)
+        {
+            return;
+        }
+
+        board.Repository.DeleteCard(card.Id);
+        board.Reload();
+    }
+
+    /// <summary>Shows the move-card dialog and reloads when a destination is chosen.</summary>
+    private async Task MoveCardAsync(BoardViewModel board, CardViewModel card)
+    {
+        if (OwningWindow is not Window owner)
+        {
+            return;
+        }
+
+        var dialog = new MoveCardDialog
+        {
+            DataContext = new MoveCardViewModel(board.Repository.GetColumns(), card.ColumnId),
+        };
+        if (await dialog.ShowDialog<long?>(owner) is long targetColumnId)
+        {
+            board.Repository.MoveCard(card.Id, targetColumnId);
+            board.Reload();
+        }
+    }
+}

YKanBan/Views/Board/CardView.axaml

@@ -0,0 +1,63 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:vm="using:YKanBan.ViewModels.Board"
+             xmlns:lang="using:YKanBan"
+             xmlns:icons="using:IconPacks.Avalonia.Lucide"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             mc:Ignorable="d" d:DesignWidth="320" d:DesignHeight="120"
+             x:Class="YKanBan.Views.Board.CardView"
+             x:DataType="vm:CardViewModel">
+
+    <Border Background="{DynamicResource CardBackgroundBrush}"
+            BorderBrush="{DynamicResource CardBorderBrush}"
+            BorderThickness="1" CornerRadius="6" Padding="8"
+            Cursor="Hand" Tapped="OnCardTapped">
+
+        <Grid RowDefinitions="Auto,Auto,Auto">
+
+            <!-- Row 1: id, title and the corner menu. -->
+            <Grid Grid.Row="0" ColumnDefinitions="Auto,*,Auto">
+                <TextBlock Grid.Column="0" Text="{Binding IdText}" FontWeight="Bold" VerticalAlignment="Center"/>
+                <TextBlock Grid.Column="1" Text="{Binding TitleText}" IsVisible="{Binding HasTitle}"
+                           VerticalAlignment="Center" Margin="4,0"
+                           TextWrapping="NoWrap" TextTrimming="CharacterEllipsis"
+                           ToolTip.Tip="{Binding TitleText}"/>
+                <Button Grid.Column="2" Padding="4,2" VerticalAlignment="Center"
+                        Tapped="OnMenuButtonTapped">
+                    <icons:PackIconLucide Kind="EllipsisVertical" Width="16" Height="16"/>
+                    <Button.Flyout>
+                        <MenuFlyout>
+                            <MenuItem Header="{x:Static lang:Resources.Card_Move}" Command="{Binding MoveCommand}"/>
+                            <MenuItem Header="{x:Static lang:Resources.Card_Delete}" Command="{Binding DeleteCommand}"/>
+                        </MenuFlyout>
+                    </Button.Flyout>
+                </Button>
+            </Grid>
+
+            <!-- Row 2: content preview. -->
+            <TextBlock Grid.Row="1" Text="{Binding PreviewContent}" IsVisible="{Binding HasContent}"
+                       TextWrapping="Wrap" FontSize="12" Opacity="0.85" Margin="0,4,0,0"/>
+
+            <!-- Row 3: tag badges. -->
+            <ItemsControl Grid.Row="2" ItemsSource="{Binding TagBadges}" IsVisible="{Binding HasTags}"
+                          Margin="0,4,0,0">
+                <ItemsControl.ItemsPanel>
+                    <ItemsPanelTemplate>
+                        <WrapPanel/>
+                    </ItemsPanelTemplate>
+                </ItemsControl.ItemsPanel>
+                <ItemsControl.ItemTemplate>
+                    <DataTemplate x:DataType="vm:TagBadgeViewModel">
+                        <Border Background="{Binding Background}" CornerRadius="8"
+                                Padding="6,2" Margin="0,0,4,4"
+                                ToolTip.Tip="{Binding ToolTipText}">
+                            <TextBlock Text="{Binding Name}" Foreground="{Binding Foreground}" FontSize="11"/>
+                        </Border>
+                    </DataTemplate>
+                </ItemsControl.ItemTemplate>
+            </ItemsControl>
+
+        </Grid>
+    </Border>
+</UserControl>

YKanBan/Views/Board/CardView.axaml.cs

@@ -0,0 +1,25 @@
+using Avalonia.Controls;
+using Avalonia.Input;
+using YKanBan.ViewModels.Board;
+
+namespace YKanBan.Views.Board;
+
+public partial class CardView : UserControl
+{
+    public CardView()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Clicking the card body opens the card editor.</summary>
+    private void OnCardTapped(object? sender, TappedEventArgs e)
+    {
+        if (DataContext is CardViewModel card)
+        {
+            card.EditCommand.Execute(null);
+        }
+    }
+
+    /// <summary>Stops the corner menu button's tap from bubbling to the card body.</summary>
+    private void OnMenuButtonTapped(object? sender, TappedEventArgs e) => e.Handled = true;
+}

YKanBan/Views/Board/ColumnView.axaml

@@ -0,0 +1,55 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:vm="using:YKanBan.ViewModels.Board"
+             xmlns:lang="using:YKanBan"
+             xmlns:icons="using:IconPacks.Avalonia.Lucide"
+             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+             mc:Ignorable="d" d:DesignWidth="320" d:DesignHeight="600"
+             x:Class="YKanBan.Views.Board.ColumnView"
+             x:DataType="vm:ColumnViewModel">
+
+    <Border Width="{Binding Width}" MinWidth="160" MaxWidth="720"
+            Background="{DynamicResource BoardColumnBackgroundBrush}"
+            BorderBrush="{DynamicResource BoardColumnBorderBrush}"
+            BorderThickness="1" CornerRadius="8" VerticalAlignment="Stretch">
+
+        <Grid RowDefinitions="Auto,*" Margin="10">
+
+            <Grid Grid.Row="0" ColumnDefinitions="*,Auto,Auto">
+                <StackPanel Grid.Column="0" Orientation="Horizontal" Spacing="6" VerticalAlignment="Center">
+                    <TextBlock Text="{Binding Title}" FontWeight="SemiBold"
+                               TextTrimming="CharacterEllipsis" ToolTip.Tip="{Binding ToolTipText}"/>
+                    <TextBlock Text="{Binding CardCount}" Opacity="0.6" VerticalAlignment="Center"/>
+                </StackPanel>
+
+                <Button Grid.Column="1" Margin="4,0,0,0" Padding="4,2"
+                        Command="{Binding AddCardCommand}"
+                        ToolTip.Tip="{x:Static lang:Resources.Column_AddCard}">
+                    <icons:PackIconLucide Kind="Plus" Width="16" Height="16"/>
+                </Button>
+
+                <Button Grid.Column="2" Margin="2,0,0,0" Padding="4,2">
+                    <icons:PackIconLucide Kind="EllipsisVertical" Width="16" Height="16"/>
+                    <Button.Flyout>
+                        <MenuFlyout>
+                            <MenuItem Header="{x:Static lang:Resources.Column_Edit}" Command="{Binding EditCommand}"/>
+                            <MenuItem Header="{x:Static lang:Resources.Column_Delete}" Command="{Binding DeleteCommand}"/>
+                        </MenuFlyout>
+                    </Button.Flyout>
+                </Button>
+            </Grid>
+
+            <ScrollViewer Grid.Row="1" VerticalScrollBarVisibility="Auto" Margin="0,8,0,0">
+                <ItemsControl ItemsSource="{Binding Cards}">
+                    <ItemsControl.ItemsPanel>
+                        <ItemsPanelTemplate>
+                            <StackPanel Spacing="8"/>
+                        </ItemsPanelTemplate>
+                    </ItemsControl.ItemsPanel>
+                </ItemsControl>
+            </ScrollViewer>
+
+        </Grid>
+    </Border>
+</UserControl>

YKanBan/Views/Board/ColumnView.axaml.cs

@@ -0,0 +1,11 @@
+using Avalonia.Controls;
+
+namespace YKanBan.Views.Board;
+
+public partial class ColumnView : UserControl
+{
+    public ColumnView()
+    {
+        InitializeComponent();
+    }
+}

YKanBan/Views/Dialogs/CardEditorDialog.axaml

@@ -0,0 +1,74 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:lang="using:YKanBan"
+        xmlns:icons="using:IconPacks.Avalonia.Lucide"
+        xmlns:conv="using:Avalonia.Data.Converters"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="520" d:DesignHeight="560"
+        x:Class="YKanBan.Views.Dialogs.CardEditorDialog"
+        x:DataType="vm:CardEditorViewModel"
+        Title="{Binding WindowTitle}"
+        Width="520" Height="560" MinWidth="520" MinHeight="560" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <ScrollViewer Grid.Row="0" VerticalScrollBarVisibility="Auto">
+            <StackPanel Spacing="6">
+
+                <TextBlock Text="{x:Static lang:Resources.CardDialog_Title}"/>
+                <TextBox Text="{Binding Title}"/>
+
+                <TextBlock Text="{x:Static lang:Resources.CardDialog_Content}" Margin="0,6,0,0"/>
+                <TextBox Text="{Binding Content}" AcceptsReturn="True" TextWrapping="Wrap"
+                         VerticalContentAlignment="Top" Height="160"/>
+
+                <TextBlock Text="{x:Static lang:Resources.CardDialog_Tags}" Margin="0,6,0,0"/>
+                <ItemsControl ItemsSource="{Binding AssignedTags}">
+                    <ItemsControl.ItemsPanel>
+                        <ItemsPanelTemplate>
+                            <WrapPanel/>
+                        </ItemsPanelTemplate>
+                    </ItemsControl.ItemsPanel>
+                    <ItemsControl.ItemTemplate>
+                        <DataTemplate x:DataType="vm:AssignedTagViewModel">
+                            <Border Background="{Binding Background}" CornerRadius="8"
+                                    Padding="6,2" Margin="0,0,4,4">
+                                <StackPanel Orientation="Horizontal" Spacing="4">
+                                    <TextBlock Text="{Binding Name}" Foreground="{Binding Foreground}"
+                                               FontSize="11" VerticalAlignment="Center"/>
+                                    <Button Command="{Binding RemoveCommand}" Padding="0"
+                                            Background="Transparent" BorderThickness="0">
+                                        <icons:PackIconLucide Kind="X" Width="10" Height="10"
+                                                            Foreground="{Binding Foreground}"/>
+                                    </Button>
+                                </StackPanel>
+                            </Border>
+                        </DataTemplate>
+                    </ItemsControl.ItemTemplate>
+                </ItemsControl>
+                <Button Content="{x:Static lang:Resources.CardDialog_AddTag}"
+                        Command="{Binding AddTagCommand}" HorizontalAlignment="Left"/>
+
+                <StackPanel Spacing="2" IsVisible="{Binding !IsNew}" Opacity="0.7" Margin="0,8,0,0">
+                    <TextBlock Text="{Binding IdLine}"/>
+                    <TextBlock Text="{Binding CreatedLine}"/>
+                    <TextBlock Text="{Binding ModifiedLine}"/>
+                </StackPanel>
+
+                <TextBlock Text="{Binding ErrorMessage}"
+                           IsVisible="{Binding ErrorMessage, Converter={x:Static conv:ObjectConverters.IsNotNull}}"
+                           Foreground="{DynamicResource ErrorTextBrush}" TextWrapping="Wrap" Margin="0,4,0,0"/>
+            </StackPanel>
+        </ScrollViewer>
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right"
+                    Spacing="8" Margin="0,16,0,0">
+            <Button Content="{x:Static lang:Resources.Common_Ok}" Click="OnOkClick" MinWidth="90" IsDefault="True"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick" MinWidth="90"
+                    IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/CardEditorDialog.axaml.cs

@@ -0,0 +1,99 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Threading;
+using YKanBan.Models;
+using YKanBan.ViewModels;
+using YKanBan.ViewModels.Dialogs;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class CardEditorDialog : Window
+{
+    private bool _allowClose;
+
+    public CardEditorDialog()
+    {
+        InitializeComponent();
+    }
+
+    protected override void OnDataContextChanged(EventArgs e)
+    {
+        base.OnDataContextChanged(e);
+        if (DataContext is CardEditorViewModel viewModel)
+        {
+            viewModel.ShowTagPicker.RegisterHandler(ShowTagPickerAsync);
+        }
+    }
+
+    /// <summary>Shows the nested tag picker, owned by this dialog.</summary>
+    private async Task<TagModel?> ShowTagPickerAsync(Unit input)
+    {
+        if (DataContext is not CardEditorViewModel viewModel)
+        {
+            return null;
+        }
+
+        var dialog = new TagPickerDialog
+        {
+            DataContext = new TagPickerViewModel(
+                viewModel.Repository,
+                viewModel.AssignedTags.Select(row => row.Tag.Id).ToList()),
+        };
+        return await dialog.ShowDialog<TagModel?>(this);
+    }
+
+    /// <summary>Writes the card and closes when accepted.</summary>
+    private void OnOkClick(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is CardEditorViewModel viewModel && viewModel.TryAccept())
+        {
+            _allowClose = true;
+            Close(true);
+        }
+    }
+
+    /// <summary>Requests a close, confirming the discard first when needed.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => _ = RequestCloseAsync();
+
+    /// <summary>Intercepts the window close button to run the discard confirmation.</summary>
+    protected override void OnClosing(WindowClosingEventArgs e)
+    {
+        base.OnClosing(e);
+        if (_allowClose)
+        {
+            return;
+        }
+
+        if (HasUnsavedChanges && DiscardConfirmEnabled)
+        {
+            e.Cancel = true;
+            Dispatcher.UIThread.Post(() => _ = RequestCloseAsync());
+        }
+        else
+        {
+            _allowClose = true;
+        }
+    }
+
+    /// <summary>Confirms the discard and closes, or stays open when declined.</summary>
+    private async Task RequestCloseAsync()
+    {
+        if (HasUnsavedChanges && DiscardConfirmEnabled)
+        {
+            var dialog = new DiscardEditConfirmDialog { DataContext = new DiscardEditConfirmViewModel() };
+            if (!await dialog.ShowDialog<bool>(this))
+            {
+                return;
+            }
+        }
+
+        _allowClose = true;
+        Close(false);
+    }
+
+    /// <summary>Gets whether the editor has unsaved changes.</summary>
+    private bool HasUnsavedChanges => DataContext is CardEditorViewModel viewModel && viewModel.HasChanges;
+
+    /// <summary>Gets whether the discard confirmation setting is enabled.</summary>
+    private static bool DiscardConfirmEnabled => App.Services?.Config.Confirmations.DiscardEdit == true;
+}

YKanBan/Views/Dialogs/ColumnEditorDialog.axaml

@@ -0,0 +1,36 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:lang="using:YKanBan"
+        xmlns:conv="using:Avalonia.Data.Converters"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="420" d:DesignHeight="300"
+        x:Class="YKanBan.Views.Dialogs.ColumnEditorDialog"
+        x:DataType="vm:ColumnEditorViewModel"
+        Title="{Binding WindowTitle}"
+        Width="420" Height="300" MinWidth="420" MinHeight="300" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <StackPanel Grid.Row="0" Spacing="6">
+            <TextBlock Text="{x:Static lang:Resources.ColumnDialog_Title}"/>
+            <TextBox Text="{Binding Title}"/>
+
+            <TextBlock Text="{x:Static lang:Resources.ColumnDialog_Description}" Margin="0,6,0,0"/>
+            <TextBox Text="{Binding Description}" AcceptsReturn="True" TextWrapping="Wrap"
+                     VerticalContentAlignment="Top" Height="80"/>
+
+            <TextBlock Text="{Binding ErrorMessage}"
+                       IsVisible="{Binding ErrorMessage, Converter={x:Static conv:ObjectConverters.IsNotNull}}"
+                       Foreground="{DynamicResource ErrorTextBrush}" TextWrapping="Wrap" Margin="0,4,0,0"/>
+        </StackPanel>
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right"
+                    Spacing="8" Margin="0,16,0,0">
+            <Button Content="{x:Static lang:Resources.Common_Ok}" Click="OnOkClick" MinWidth="90" IsDefault="True"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick" MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/ColumnEditorDialog.axaml.cs

@@ -0,0 +1,25 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using YKanBan.ViewModels.Dialogs;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class ColumnEditorDialog : Window
+{
+    public ColumnEditorDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Writes the column and closes when accepted.</summary>
+    private void OnOkClick(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is ColumnEditorViewModel viewModel && viewModel.TryAccept())
+        {
+            Close(true);
+        }
+    }
+
+    /// <summary>Closes without writing.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(false);
+}

YKanBan/Views/Dialogs/DeleteCardConfirmDialog.axaml

@@ -0,0 +1,24 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:lang="using:YKanBan"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="420" d:DesignHeight="200"
+        x:Class="YKanBan.Views.Dialogs.DeleteCardConfirmDialog"
+        x:DataType="vm:DeleteCardConfirmViewModel"
+        Title="{x:Static lang:Resources.Confirm_DeleteCard_Title}"
+        Width="420" Height="200" MinWidth="420" MinHeight="200" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <TextBlock Grid.Row="0" Text="{Binding Message}" TextWrapping="Wrap" VerticalAlignment="Top"/>
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8">
+            <Button Content="{x:Static lang:Resources.Common_Delete}" Click="OnConfirmClick"
+                    MinWidth="90" IsDefault="True"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick"
+                    MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/DeleteCardConfirmDialog.axaml.cs

@@ -0,0 +1,18 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class DeleteCardConfirmDialog : Window
+{
+    public DeleteCardConfirmDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Confirms the deletion.</summary>
+    private void OnConfirmClick(object? sender, RoutedEventArgs e) => Close(true);
+
+    /// <summary>Cancels the deletion.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(false);
+}

YKanBan/Views/Dialogs/DeleteColumnConfirmDialog.axaml

@@ -0,0 +1,24 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:lang="using:YKanBan"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="420" d:DesignHeight="200"
+        x:Class="YKanBan.Views.Dialogs.DeleteColumnConfirmDialog"
+        x:DataType="vm:DeleteColumnConfirmViewModel"
+        Title="{x:Static lang:Resources.Confirm_DeleteColumn_Title}"
+        Width="420" Height="200" MinWidth="420" MinHeight="200" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <TextBlock Grid.Row="0" Text="{Binding Message}" TextWrapping="Wrap" VerticalAlignment="Top"/>
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8">
+            <Button Content="{x:Static lang:Resources.Common_Delete}" Click="OnConfirmClick"
+                    MinWidth="90" IsDefault="True"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick"
+                    MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/DeleteColumnConfirmDialog.axaml.cs

@@ -0,0 +1,18 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class DeleteColumnConfirmDialog : Window
+{
+    public DeleteColumnConfirmDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Confirms the deletion.</summary>
+    private void OnConfirmClick(object? sender, RoutedEventArgs e) => Close(true);
+
+    /// <summary>Cancels the deletion.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(false);
+}

YKanBan/Views/Dialogs/DiscardEditConfirmDialog.axaml

@@ -0,0 +1,24 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:lang="using:YKanBan"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="420" d:DesignHeight="200"
+        x:Class="YKanBan.Views.Dialogs.DiscardEditConfirmDialog"
+        x:DataType="vm:DiscardEditConfirmViewModel"
+        Title="{x:Static lang:Resources.Confirm_Discard_Title}"
+        Width="420" Height="200" MinWidth="420" MinHeight="200" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <TextBlock Grid.Row="0" Text="{Binding Message}" TextWrapping="Wrap" VerticalAlignment="Top"/>
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8">
+            <Button Content="{x:Static lang:Resources.Common_Ok}" Click="OnConfirmClick"
+                    MinWidth="90" IsDefault="True"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick"
+                    MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/DiscardEditConfirmDialog.axaml.cs

@@ -0,0 +1,18 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class DiscardEditConfirmDialog : Window
+{
+    public DiscardEditConfirmDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Confirms discarding the changes.</summary>
+    private void OnConfirmClick(object? sender, RoutedEventArgs e) => Close(true);
+
+    /// <summary>Keeps editing.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(false);
+}

YKanBan/Views/Dialogs/MoveCardDialog.axaml

@@ -0,0 +1,39 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:vmBase="using:YKanBan.ViewModels"
+        xmlns:lang="using:YKanBan"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="380" d:DesignHeight="200"
+        x:Class="YKanBan.Views.Dialogs.MoveCardDialog"
+        x:DataType="vm:MoveCardViewModel"
+        Title="{x:Static lang:Resources.MoveDialog_Title}"
+        Width="380" Height="200" MinWidth="380" MinHeight="200" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <StackPanel Grid.Row="0" Spacing="6">
+            <TextBlock Text="{x:Static lang:Resources.MoveDialog_Target}"/>
+            <ComboBox ItemsSource="{Binding Targets}" SelectedItem="{Binding SelectedTarget}"
+                      HorizontalAlignment="Stretch">
+                <ComboBox.ItemTemplate>
+                    <DataTemplate x:DataType="vmBase:OptionItem">
+                        <TextBlock Text="{Binding Label}"/>
+                    </DataTemplate>
+                </ComboBox.ItemTemplate>
+            </ComboBox>
+            <TextBlock Text="{x:Static lang:Resources.MoveDialog_NoTargets}"
+                       IsVisible="{Binding !CanMove}" Opacity="0.7" TextWrapping="Wrap"/>
+        </StackPanel>
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right"
+                    Spacing="8" Margin="0,16,0,0">
+            <Button Content="{x:Static lang:Resources.Common_Ok}" Click="OnOkClick"
+                    MinWidth="90" IsDefault="True" IsEnabled="{Binding CanMove}"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick"
+                    MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/MoveCardDialog.axaml.cs

@@ -0,0 +1,25 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using YKanBan.ViewModels.Dialogs;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class MoveCardDialog : Window
+{
+    public MoveCardDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Closes with the selected destination column id.</summary>
+    private void OnOkClick(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is MoveCardViewModel viewModel && viewModel.SelectedTarget is not null)
+        {
+            Close((long)viewModel.SelectedTarget.Value);
+        }
+    }
+
+    /// <summary>Closes without moving.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(null);
+}

YKanBan/Views/Dialogs/TagPickerDialog.axaml

@@ -0,0 +1,42 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:vm="using:YKanBan.ViewModels.Dialogs"
+        xmlns:board="using:YKanBan.ViewModels.Board"
+        xmlns:lang="using:YKanBan"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        mc:Ignorable="d" d:DesignWidth="380" d:DesignHeight="200"
+        x:Class="YKanBan.Views.Dialogs.TagPickerDialog"
+        x:DataType="vm:TagPickerViewModel"
+        Title="{x:Static lang:Resources.TagDialog_Title}"
+        Width="380" Height="200" MinWidth="380" MinHeight="200" CanResize="True"
+        WindowStartupLocation="CenterOwner"
+        ShowInTaskbar="False">
+
+    <Grid RowDefinitions="*,Auto" Margin="20">
+        <StackPanel Grid.Row="0" Spacing="6">
+            <TextBlock Text="{x:Static lang:Resources.TagDialog_Target}"/>
+            <ComboBox ItemsSource="{Binding Targets}" SelectedItem="{Binding SelectedTarget}"
+                      HorizontalAlignment="Stretch">
+                <ComboBox.ItemTemplate>
+                    <DataTemplate x:DataType="board:TagBadgeViewModel">
+                        <StackPanel Orientation="Horizontal" Spacing="8">
+                            <Border Width="14" Height="14" CornerRadius="3" Background="{Binding Background}"/>
+                            <TextBlock Text="{Binding Name}" VerticalAlignment="Center"/>
+                        </StackPanel>
+                    </DataTemplate>
+                </ComboBox.ItemTemplate>
+            </ComboBox>
+            <TextBlock Text="{x:Static lang:Resources.TagDialog_NoTargets}"
+                       IsVisible="{Binding !CanAdd}" Opacity="0.7" TextWrapping="Wrap"/>
+        </StackPanel>
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Right"
+                    Spacing="8" Margin="0,16,0,0">
+            <Button Content="{x:Static lang:Resources.Common_Ok}" Click="OnOkClick"
+                    MinWidth="90" IsDefault="True" IsEnabled="{Binding CanAdd}"/>
+            <Button Content="{x:Static lang:Resources.Common_Cancel}" Click="OnCancelClick"
+                    MinWidth="90" IsCancel="True"/>
+        </StackPanel>
+    </Grid>
+</Window>

YKanBan/Views/Dialogs/TagPickerDialog.axaml.cs

@@ -0,0 +1,25 @@
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using YKanBan.ViewModels.Dialogs;
+
+namespace YKanBan.Views.Dialogs;
+
+public partial class TagPickerDialog : Window
+{
+    public TagPickerDialog()
+    {
+        InitializeComponent();
+    }
+
+    /// <summary>Closes with the selected tag.</summary>
+    private void OnOkClick(object? sender, RoutedEventArgs e)
+    {
+        if (DataContext is TagPickerViewModel viewModel && viewModel.SelectedTarget is { } badge)
+        {
+            Close(badge.Tag);
+        }
+    }
+
+    /// <summary>Closes without picking a tag.</summary>
+    private void OnCancelClick(object? sender, RoutedEventArgs e) => Close(null);
+}

YKanBan/Views/WorkspaceView.axaml

@@ -3,6 +3,7 @@
              xmlns:vm="using:YKanBan.ViewModels"
              xmlns:lang="using:YKanBan"
              xmlns:icons="using:IconPacks.Avalonia.Lucide"
+             xmlns:board="using:YKanBan.Views.Board"
              xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              mc:Ignorable="d" d:DesignWidth="1000" d:DesignHeight="640"
@@ -50,7 +51,9 @@
 
         <!-- Tags and board tabs; their contents arrive with the corresponding features. -->
         <TabControl Grid.Row="1" Margin="8">
-            <TabItem Header="{x:Static lang:Resources.Tab_Board}"/>
+            <TabItem Header="{x:Static lang:Resources.Tab_Board}">
+                <board:BoardView DataContext="{Binding Board}"/>
+            </TabItem>
             <TabItem Header="{x:Static lang:Resources.Tab_Tags}"/>
         </TabControl>