diff --git a/CMakeLists.txt b/CMakeLists.txt
index d2ed4a6..e6107d8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,6 +33,8 @@ PRIVATE
     main.cpp
     mainwindow.cpp mainwindow.h
     sciedit.cpp sciedit.h
+    tabwidget.cpp tabwidget.h
+    documentmanager.cpp documentmanager.h
     editorviewhelper.cpp editorviewhelper.h
     generalsettings.ui
 
diff --git a/documentmanager.cpp b/documentmanager.cpp
new file mode 100644
index 0000000..3e8bb06
--- /dev/null
+++ b/documentmanager.cpp
@@ -0,0 +1,275 @@
+#include "documentmanager.h"
+
+#include <QFile>
+#include <QFileInfo>
+#include <QTextStream>
+#include <QDebug>
+
+int DocumentManager::s_untitledCounter = 1;
+
+DocumentManager::DocumentManager(QObject *parent)
+    : QObject(parent)
+    , m_nextDocumentId(1)
+{
+}
+
+DocumentManager::~DocumentManager()
+{
+}
+
+int DocumentManager::createNewDocument()
+{
+    DocumentInfo doc;
+    doc.id = m_nextDocumentId++;
+    doc.title = generateUntitledName();
+    doc.filePath = QString();
+    doc.content = QString();
+    doc.encoding = "UTF-8";
+    doc.language = "Plain Text";
+    doc.modified = false;
+    doc.untitled = true;
+
+    m_documents[doc.id] = doc;
+    
+    emit documentCreated(doc.id);
+    return doc.id;
+}
+
+int DocumentManager::openDocument(const QString &filePath)
+{
+    QFile file(filePath);
+    if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
+        qWarning() << "Failed to open file:" << filePath;
+        return -1;
+    }
+
+    QTextStream in(&file);
+    in.setEncoding(QStringConverter::Utf8);
+    QString content = in.readAll();
+    file.close();
+
+    DocumentInfo doc;
+    doc.id = m_nextDocumentId++;
+    doc.title = QFileInfo(filePath).fileName();
+    doc.filePath = filePath;
+    doc.content = content;
+    doc.encoding = "UTF-8";
+    doc.language = detectLanguageFromExtension(filePath);
+    doc.modified = false;
+    doc.untitled = false;
+
+    m_documents[doc.id] = doc;
+    
+    emit documentOpened(doc.id, filePath);
+    return doc.id;
+}
+
+bool DocumentManager::saveDocument(int docId)
+{
+    if (!m_documents.contains(docId)) {
+        return false;
+    }
+
+    DocumentInfo &doc = m_documents[docId];
+    if (doc.untitled || doc.filePath.isEmpty()) {
+        return false; // 需要使用 saveAs
+    }
+
+    QFile file(doc.filePath);
+    if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
+        qWarning() << "Failed to save file:" << doc.filePath;
+        return false;
+    }
+
+    QTextStream out(&file);
+    out.setEncoding(QStringConverter::Utf8);
+    out << doc.content;
+    file.close();
+
+    doc.modified = false;
+    emit documentSaved(docId, doc.filePath);
+    emit documentModified(docId, false);
+    
+    return true;
+}
+
+bool DocumentManager::saveDocumentAs(int docId, const QString &filePath)
+{
+    if (!m_documents.contains(docId)) {
+        return false;
+    }
+
+    DocumentInfo &doc = m_documents[docId];
+    
+    QFile file(filePath);
+    if (!file.open(QIODevice::WriteOnly | QIODevice::Text)) {
+        qWarning() << "Failed to save file as:" << filePath;
+        return false;
+    }
+
+    QTextStream out(&file);
+    out.setEncoding(QStringConverter::Utf8);
+    out << doc.content;
+    file.close();
+
+    // 更新文档信息
+    doc.filePath = filePath;
+    doc.title = QFileInfo(filePath).fileName();
+    doc.language = detectLanguageFromExtension(filePath);
+    doc.modified = false;
+    doc.untitled = false;
+
+    emit documentSaved(docId, filePath);
+    emit documentModified(docId, false);
+    emit documentTitleChanged(docId, doc.title);
+    
+    return true;
+}
+
+void DocumentManager::closeDocument(int docId)
+{
+    if (m_documents.contains(docId)) {
+        m_documents.remove(docId);
+        emit documentClosed(docId);
+    }
+}
+
+QString DocumentManager::getDocumentTitle(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].title;
+    }
+    return QString();
+}
+
+QString DocumentManager::getDocumentFilePath(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].filePath;
+    }
+    return QString();
+}
+
+QString DocumentManager::getDocumentContent(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].content;
+    }
+    return QString();
+}
+
+QString DocumentManager::getDocumentEncoding(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].encoding;
+    }
+    return "UTF-8";
+}
+
+QString DocumentManager::getDocumentLanguage(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].language;
+    }
+    return "Plain Text";
+}
+
+bool DocumentManager::isDocumentModified(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].modified;
+    }
+    return false;
+}
+
+bool DocumentManager::isDocumentUntitled(int docId) const
+{
+    if (m_documents.contains(docId)) {
+        return m_documents[docId].untitled;
+    }
+    return true;
+}
+
+void DocumentManager::setDocumentContent(int docId, const QString &content)
+{
+    if (m_documents.contains(docId)) {
+        DocumentInfo &doc = m_documents[docId];
+        if (doc.content != content) {
+            doc.content = content;
+            if (!doc.modified) {
+                doc.modified = true;
+                emit documentModified(docId, true);
+            }
+        }
+    }
+}
+
+void DocumentManager::setDocumentModified(int docId, bool modified)
+{
+    if (m_documents.contains(docId)) {
+        DocumentInfo &doc = m_documents[docId];
+        if (doc.modified != modified) {
+            doc.modified = modified;
+            emit documentModified(docId, modified);
+        }
+    }
+}
+
+void DocumentManager::setDocumentEncoding(int docId, const QString &encoding)
+{
+    if (m_documents.contains(docId)) {
+        m_documents[docId].encoding = encoding;
+    }
+}
+
+void DocumentManager::setDocumentLanguage(int docId, const QString &language)
+{
+    if (m_documents.contains(docId)) {
+        m_documents[docId].language = language;
+    }
+}
+
+QList<int> DocumentManager::getAllDocumentIds() const
+{
+    return m_documents.keys();
+}
+
+int DocumentManager::getDocumentCount() const
+{
+    return m_documents.size();
+}
+
+QString DocumentManager::generateUntitledName()
+{
+    return QString("Untitled-%1").arg(s_untitledCounter++);
+}
+
+QString DocumentManager::detectLanguageFromExtension(const QString &filePath)
+{
+    QFileInfo fileInfo(filePath);
+    QString extension = fileInfo.suffix().toLower();
+    
+    if (extension == "cpp" || extension == "cxx" || extension == "cc" || extension == "c++") {
+        return "C++";
+    } else if (extension == "c") {
+        return "C";
+    } else if (extension == "h" || extension == "hpp" || extension == "hxx") {
+        return "C/C++ Header";
+    } else if (extension == "py") {
+        return "Python";
+    } else if (extension == "js") {
+        return "JavaScript";
+    } else if (extension == "html" || extension == "htm") {
+        return "HTML";
+    } else if (extension == "css") {
+        return "CSS";
+    } else if (extension == "xml") {
+        return "XML";
+    } else if (extension == "json") {
+        return "JSON";
+    } else if (extension == "txt") {
+        return "Plain Text";
+    } else {
+        return "Plain Text";
+    }
+}
\ No newline at end of file
diff --git a/documentmanager.h b/documentmanager.h
new file mode 100644
index 0000000..27dac58
--- /dev/null
+++ b/documentmanager.h
@@ -0,0 +1,69 @@
+#pragma once
+
+#include <QObject>
+#include <QHash>
+#include <QString>
+#include <QStringList>
+#include <QTextCodec>
+
+class DocumentManager : public QObject
+{
+    Q_OBJECT
+
+public:
+    explicit DocumentManager(QObject *parent = nullptr);
+    ~DocumentManager();
+
+    // 文档管理
+    int createNewDocument();
+    int openDocument(const QString &filePath);
+    bool saveDocument(int docId);
+    bool saveDocumentAs(int docId, const QString &filePath);
+    void closeDocument(int docId);
+
+    // 文档信息
+    QString getDocumentTitle(int docId) const;
+    QString getDocumentFilePath(int docId) const;
+    QString getDocumentContent(int docId) const;
+    QString getDocumentEncoding(int docId) const;
+    QString getDocumentLanguage(int docId) const;
+    bool isDocumentModified(int docId) const;
+    bool isDocumentUntitled(int docId) const;
+
+    // 文档内容操作
+    void setDocumentContent(int docId, const QString &content);
+    void setDocumentModified(int docId, bool modified);
+    void setDocumentEncoding(int docId, const QString &encoding);
+    void setDocumentLanguage(int docId, const QString &language);
+
+    // 获取所有文档
+    QList<int> getAllDocumentIds() const;
+    int getDocumentCount() const;
+
+signals:
+    void documentCreated(int docId);
+    void documentOpened(int docId, const QString &filePath);
+    void documentSaved(int docId, const QString &filePath);
+    void documentClosed(int docId);
+    void documentModified(int docId, bool modified);
+    void documentTitleChanged(int docId, const QString &title);
+
+private:
+    struct DocumentInfo {
+        int id;
+        QString title;
+        QString filePath;
+        QString content;
+        QString encoding;
+        QString language;
+        bool modified;
+        bool untitled;
+    };
+
+    QHash<int, DocumentInfo> m_documents;
+    int m_nextDocumentId;
+    static int s_untitledCounter;
+
+    QString generateUntitledName();
+    QString detectLanguageFromExtension(const QString &filePath);
+};
diff --git a/mainwindow.cpp b/mainwindow.cpp
index 52d3025..1810d3c 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -1,6 +1,8 @@
 #include "mainwindow.h"
 
 #include "sciedit.h"
+#include "tabwidget.h"
+#include "documentmanager.h"
 #include "appsettings.h"
 #include "editorviewhelper.h"
 
@@ -9,6 +11,8 @@
 #include <QMenu>
 #include <QStringBuilder>
 #include <QStatusBar>
+#include <QFileDialog>
+#include <QMessageBox>
 
 #include <KActionCollection>
 #include <KStandardAction>
@@ -23,30 +27,29 @@
 
 MainWindow::MainWindow(QWidget *parent)
     : KXmlGuiWindow(parent)
-    , m_editor(new SciEdit(this))
+    , m_documentManager(new DocumentManager(this))
+    , m_tabWidget(new TabWidget(m_documentManager, this))
     , m_cursorPosStatusLabel(new QLabel(QString("Ln: ?  Col: ?"), this))
+    , m_encodingStatusLabel(new QLabel(QString("UTF-8"), this))
+    , m_languageStatusLabel(new QLabel(QString("Plain Text"), this))
 {
-    setCentralWidget(m_editor);
+    setCentralWidget(m_tabWidget);
 
+    // 设置状态栏
     statusBar()->addPermanentWidget(m_cursorPosStatusLabel);
+    statusBar()->addPermanentWidget(m_encodingStatusLabel);
+    statusBar()->addPermanentWidget(m_languageStatusLabel);
 
-    QFont font(AppSettings::self()->editorFont());
-    m_editor->setStyleFont(font);
-    m_editor->setStyleFont(font, STYLE_LINENUMBER);
-
-    m_editor->setMarginTypeN(1, SC_MARGIN_NUMBER);
-    m_editor->setMarginWidthN(1, m_editor->textWidth(STYLE_LINENUMBER, "_99999"));
-    m_editor->setFolding(SciEdit::BoxFoldType);
-    // m_editor->setBraceMatching(QsciScintilla::SloppyBraceMatch);
-
-    m_editor->setTabWidth(AppSettings::self()->tabWidth());
-    m_editor->setEOLMode(SC_EOL_LF);
-
-    connect(m_editor, &SciEdit::cursorPosChanged, this, [this](int line, int index){
-        m_cursorPosStatusLabel->setText(QString("Ln: %1  Col: %2").arg(line).arg(index));
-    });
+    // 连接标签页信号
+    connect(m_tabWidget, &TabWidget::currentEditorChanged, this, &MainWindow::onCurrentEditorChanged);
+    
+    // 连接文档管理器信号
+    connect(m_documentManager, &DocumentManager::documentModified, this, &MainWindow::onDocumentModified);
 
     setupActions();
+    
+    // 创建第一个标签页
+    newFile();
 }
 
 MainWindow::~MainWindow()
@@ -58,27 +61,40 @@ void MainWindow::setupActions()
     using namespace Qt::Literals::StringLiterals;
 
     // "File" menu
-    KStandardAction::openNew(this, [](){}, actionCollection());
-    KStandardAction::open(this, [](){}, actionCollection());
-    KStandardAction::save(this, [](){}, actionCollection());
-    KStandardAction::close(this, [](){}, actionCollection());
+    KStandardAction::openNew(this, &MainWindow::newFile, actionCollection());
+    KStandardAction::open(this, &MainWindow::openFile, actionCollection());
+    KStandardAction::save(this, &MainWindow::saveFile, actionCollection());
+    KStandardAction::close(this, &MainWindow::closeFile, actionCollection());
     KStandardAction::quit(qApp, &QApplication::quit, actionCollection());
+    
+    // 添加另存为动作
+    QAction *saveAsAction = KStandardAction::saveAs(this, &MainWindow::saveAsFile, actionCollection());
 
     // "Edit" menu
     KStandardAction::undo(this, [this](){
-        m_editor->undo();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->undo();
+        }
     }, actionCollection());
     KStandardAction::redo(this, [this](){
-        m_editor->redo();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->redo();
+        }
     }, actionCollection());
     KStandardAction::cut(this, [this](){
-        m_editor->cut();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->cut();
+        }
     }, actionCollection());
     KStandardAction::copy(this, [this](){
-        m_editor->copy();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->copy();
+        }
     }, actionCollection());
     KStandardAction::paste(this, [this](){
-        m_editor->paste();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->paste();
+        }
     }, actionCollection());
 
     // "Search" menu
@@ -104,10 +120,14 @@ void MainWindow::setupActions()
 
     // Toolbar actions
     KStandardAction::zoomIn(this, [this](){
-        m_editor->zoomIn();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->zoomIn();
+        }
     }, actionCollection());
     KStandardAction::zoomOut(this, [this](){
-        m_editor->zoomOut();
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            editor->zoomOut();
+        }
     }, actionCollection());
 
     KStandardAction::preferences(this, &MainWindow::showSettings, actionCollection());
@@ -118,9 +138,11 @@ void MainWindow::setupActions()
     toggleWrapModeAction->setCheckable(true);
     actionCollection()->addAction(u"toggle_wrap_mode"_s, toggleWrapModeAction);
     connect(toggleWrapModeAction, &QAction::triggered, this, [this, toggleWrapModeAction](){
-        bool switchToWrapNone = m_editor->wrapMode() == SC_WRAP_WORD;
-        m_editor->setWrapMode(switchToWrapNone ? SC_WRAP_NONE : SC_WRAP_WORD);
-        toggleWrapModeAction->setChecked(!switchToWrapNone);
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            bool switchToWrapNone = editor->wrapMode() == SC_WRAP_WORD;
+            editor->setWrapMode(switchToWrapNone ? SC_WRAP_NONE : SC_WRAP_WORD);
+            toggleWrapModeAction->setChecked(!switchToWrapNone);
+        }
     });
 
     QAction *toggleWhitespaceVisibilityAction = new QAction(this);
@@ -129,10 +151,12 @@ void MainWindow::setupActions()
     // toggleWhitespaceVisibilityAction->setIcon(QIcon::fromTheme(u"text-wrap"_s));
     actionCollection()->addAction(u"toggle_show_all_characters"_s, toggleWhitespaceVisibilityAction);
     connect(toggleWhitespaceVisibilityAction, &QAction::triggered, this, [this, toggleWhitespaceVisibilityAction](){
-        bool switchToVisible = m_editor->viewWS() == SCWS_INVISIBLE;
-        m_editor->setViewWS(switchToVisible ? SCWS_VISIBLEALWAYS : SCWS_INVISIBLE);
-        m_editor->setViewEOL(switchToVisible);
-        toggleWhitespaceVisibilityAction->setChecked(switchToVisible);
+        if (SciEdit *editor = m_tabWidget->currentEditor()) {
+            bool switchToVisible = editor->viewWS() == SCWS_INVISIBLE;
+            editor->setViewWS(switchToVisible ? SCWS_VISIBLEALWAYS : SCWS_INVISIBLE);
+            editor->setViewEOL(switchToVisible);
+            toggleWhitespaceVisibilityAction->setChecked(switchToVisible);
+        }
     });
 
     QAction *toggleIndentGuideAction = new QAction(this);
@@ -144,7 +168,7 @@ void MainWindow::setupActions()
     });
 
     // Load themes
-    KColorSchemeManager *manager = new KColorSchemeManager(this);
+    KColorSchemeManager *manager = KColorSchemeManager::instance();
     auto *colorSelectionMenu = KColorSchemeMenu::createMenu(manager, this);
     colorSelectionMenu->menu()->setTitle("&Window Color Scheme");
     actionCollection()->addAction(QStringLiteral("colorscheme_menu"), colorSelectionMenu);
@@ -170,6 +194,127 @@ void MainWindow::showSettings()
 
 void MainWindow::applyLexer(const QString &lexerName)
 {
-    Scintilla::ILexer5 * lexer = CreateLexer(lexerName.toStdString().c_str());
-    m_editor->setLexer(lexer);
+    if (SciEdit *editor = m_tabWidget->currentEditor()) {
+        Scintilla::ILexer5 * lexer = CreateLexer(lexerName.toStdString().c_str());
+        editor->setLexer(lexer);
+    }
+}
+
+void MainWindow::newFile()
+{
+    m_tabWidget->newDocument();
+}
+
+void MainWindow::openFile()
+{
+    QString fileName = QFileDialog::getOpenFileName(this, 
+        tr("Open File"), 
+        QString(), 
+        tr("All Files (*.*)"));
+    
+    if (!fileName.isEmpty()) {
+        m_tabWidget->openDocument(fileName);
+    }
+}
+
+void MainWindow::saveFile()
+{
+    m_tabWidget->saveCurrentDocument();
+}
+
+void MainWindow::saveAsFile()
+{
+    m_tabWidget->saveCurrentDocumentAs();
+}
+
+void MainWindow::closeFile()
+{
+    m_tabWidget->closeCurrentTab();
+}
+
+void MainWindow::onCurrentTabChanged()
+{
+    updateWindowTitle();
+    updateStatusBar();
+    updateActions();
+}
+
+void MainWindow::onCurrentEditorChanged(SciEdit *editor)
+{
+    Q_UNUSED(editor)
+    updateWindowTitle();
+    updateStatusBar();
+    updateActions();
+    
+    // 连接当前编辑器的光标位置变化信号
+    if (editor) {
+        connect(editor, &SciEdit::cursorPosChanged, this, [this](int line, int column) {
+            m_cursorPosStatusLabel->setText(QString("Ln: %1  Col: %2").arg(line).arg(column));
+        });
+    }
+}
+
+void MainWindow::onDocumentModified(int docIndex, bool modified)
+{
+    Q_UNUSED(docIndex)
+    Q_UNUSED(modified)
+    updateWindowTitle();
+}
+
+void MainWindow::updateWindowTitle()
+{
+    QString title = "Pineapple Notepad";
+    
+    if (SciEdit *editor = m_tabWidget->currentEditor()) {
+        int docId = m_tabWidget->currentDocumentId();
+        if (docId >= 0) {
+            QString fileName = m_documentManager->getDocumentTitle(docId);
+            bool isModified = m_documentManager->isDocumentModified(docId);
+            
+            title = QString("%1%2 - Pineapple Notepad")
+                    .arg(fileName)
+                    .arg(isModified ? "*" : "");
+        }
+    }
+    
+    setWindowTitle(title);
+}
+
+void MainWindow::updateStatusBar()
+{
+    if (SciEdit *editor = m_tabWidget->currentEditor()) {
+        int docId = m_tabWidget->currentDocumentId();
+        if (docId >= 0) {
+            QString encoding = m_documentManager->getDocumentEncoding(docId);
+            QString language = m_documentManager->getDocumentLanguage(docId);
+            
+            m_encodingStatusLabel->setText(encoding);
+            m_languageStatusLabel->setText(language);
+        }
+    } else {
+        m_encodingStatusLabel->setText("UTF-8");
+        m_languageStatusLabel->setText("Plain Text");
+    }
+}
+
+void MainWindow::updateActions()
+{
+    bool hasEditor = (m_tabWidget->currentEditor() != nullptr);
+    
+    // 更新编辑相关的动作状态
+    if (QAction *undoAction = actionCollection()->action(KStandardAction::name(KStandardAction::Undo))) {
+        undoAction->setEnabled(hasEditor);
+    }
+    if (QAction *redoAction = actionCollection()->action(KStandardAction::name(KStandardAction::Redo))) {
+        redoAction->setEnabled(hasEditor);
+    }
+    if (QAction *cutAction = actionCollection()->action(KStandardAction::name(KStandardAction::Cut))) {
+        cutAction->setEnabled(hasEditor);
+    }
+    if (QAction *copyAction = actionCollection()->action(KStandardAction::name(KStandardAction::Copy))) {
+        copyAction->setEnabled(hasEditor);
+    }
+    if (QAction *pasteAction = actionCollection()->action(KStandardAction::name(KStandardAction::Paste))) {
+        pasteAction->setEnabled(hasEditor);
+    }
 }
diff --git a/mainwindow.h b/mainwindow.h
index 7796871..ea029ac 100644
--- a/mainwindow.h
+++ b/mainwindow.h
@@ -6,6 +6,9 @@
 
 class QLabel;
 class SciEdit;
+class TabWidget;
+class DocumentManager;
+
 class MainWindow : public KXmlGuiWindow
 {
     Q_OBJECT
@@ -14,13 +17,29 @@ public:
     explicit MainWindow(QWidget *parent = nullptr);
     ~MainWindow();
 
+private slots:
+    void newFile();
+    void openFile();
+    void saveFile();
+    void saveAsFile();
+    void closeFile();
+    void onCurrentTabChanged();
+    void onCurrentEditorChanged(SciEdit *editor);
+    void onDocumentModified(int docIndex, bool modified);
+
 private:
     void setupActions();
     void showSettings();
     void applyLexer(const QString & lexer);
+    void updateWindowTitle();
+    void updateStatusBar();
+    void updateActions();
 
-    SciEdit * m_editor;
-    QLabel * m_cursorPosStatusLabel;
+    DocumentManager *m_documentManager;
+    TabWidget *m_tabWidget;
+    QLabel *m_cursorPosStatusLabel;
+    QLabel *m_encodingStatusLabel;
+    QLabel *m_languageStatusLabel;
 };
 
 // plainly for KConfigDialog
diff --git a/sciedit.cpp b/sciedit.cpp
index f022755..c48f62f 100644
--- a/sciedit.cpp
+++ b/sciedit.cpp
@@ -7,6 +7,10 @@ SciEdit::SciEdit(QWidget * parent)
         int curPos = currentPos();
         emit cursorPosChanged(lineFromPosition(curPos) + 1, column(curPos));
     });
+    
+    // 连接文本变化信号
+    connect(this, QOverload<Scintilla::ModificationFlags, Scintilla::Position, Scintilla::Position, Scintilla::Position, const QByteArray &, Scintilla::Position, Scintilla::FoldLevel, Scintilla::FoldLevel>::of(&ScintillaEditBase::modified), 
+            this, &SciEdit::textChanged);
 }
 
 void SciEdit::setStyleFont(const QFont &font, int style)
diff --git a/sciedit.h b/sciedit.h
index 55c2685..456738f 100644
--- a/sciedit.h
+++ b/sciedit.h
@@ -22,6 +22,7 @@ public:
 
 signals:
     void cursorPosChanged(int line, int index);
+    void textChanged();
 
 private:
     void setMarkerDefine(int markerNumber, int markerSymbol);
diff --git a/tabwidget.cpp b/tabwidget.cpp
new file mode 100644
index 0000000..97a21ee
--- /dev/null
+++ b/tabwidget.cpp
@@ -0,0 +1,358 @@
+#include "tabwidget.h"
+#include "sciedit.h"
+#include "documentmanager.h"
+
+#include <QFileDialog>
+#include <QMessageBox>
+#include <QDebug>
+
+TabWidget::TabWidget(DocumentManager *documentManager, QWidget *parent)
+    : QTabWidget(parent)
+    , m_documentManager(documentManager)
+{
+    setTabsClosable(true);
+    setMovable(true);
+    setUsesScrollButtons(true);
+    
+    // 连接信号
+    connect(this, &QTabWidget::currentChanged, this, &TabWidget::onCurrentChanged);
+    connect(this, &QTabWidget::tabCloseRequested, this, &TabWidget::onTabCloseRequested);
+    
+    // 连接文档管理器信号
+    connect(m_documentManager, &DocumentManager::documentModified, 
+            this, &TabWidget::onDocumentModified);
+    connect(m_documentManager, &DocumentManager::documentTitleChanged,
+            this, &TabWidget::onDocumentTitleChanged);
+    
+    // 创建第一个文档
+    newDocument();
+}
+
+TabWidget::~TabWidget()
+{
+}
+
+int TabWidget::newDocument()
+{
+    int docId = m_documentManager->createNewDocument();
+    if (docId == -1) {
+        return -1;
+    }
+    
+    SciEdit *editor = createEditor();
+    m_editors[docId] = editor;
+    
+    QString title = m_documentManager->getDocumentTitle(docId);
+    int tabIndex = addTab(editor, title);
+    
+    m_tabToDocumentId[tabIndex] = docId;
+    m_documentIdToTab[docId] = tabIndex;
+    
+    setCurrentIndex(tabIndex);
+    
+    return docId;
+}
+
+int TabWidget::openDocument(const QString &filePath)
+{
+    int docId = m_documentManager->openDocument(filePath);
+    if (docId == -1) {
+        QMessageBox::warning(this, "Error", "Failed to open file: " + filePath);
+        return -1;
+    }
+    
+    SciEdit *editor = createEditor();
+    m_editors[docId] = editor;
+    
+    // 设置编辑器内容
+    QString content = m_documentManager->getDocumentContent(docId);
+    editor->setText(content.toUtf8().constData());
+    
+    QString title = m_documentManager->getDocumentTitle(docId);
+    int tabIndex = addTab(editor, title);
+    
+    m_tabToDocumentId[tabIndex] = docId;
+    m_documentIdToTab[docId] = tabIndex;
+    
+    setCurrentIndex(tabIndex);
+    
+    return docId;
+}
+
+bool TabWidget::saveCurrentDocument()
+{
+    SciEdit *editor = currentEditor();
+    if (!editor) {
+        return false;
+    }
+    
+    int docId = currentDocumentId();
+    if (docId == -1) {
+        return false;
+    }
+    
+    // 更新文档内容
+    QByteArray content = editor->getText(editor->textLength());
+    m_documentManager->setDocumentContent(docId, QString::fromUtf8(content));
+    
+    if (m_documentManager->isDocumentUntitled(docId)) {
+        return saveCurrentDocumentAs();
+    }
+    
+    return m_documentManager->saveDocument(docId);
+}
+
+bool TabWidget::saveCurrentDocumentAs()
+{
+    SciEdit *editor = currentEditor();
+    if (!editor) {
+        return false;
+    }
+    
+    int docId = currentDocumentId();
+    if (docId == -1) {
+        return false;
+    }
+    
+    QString fileName = QFileDialog::getSaveFileName(this, 
+        "Save File", 
+        m_documentManager->getDocumentTitle(docId),
+        "All Files (*.*)");
+    
+    if (fileName.isEmpty()) {
+        return false;
+    }
+    
+    // 更新文档内容
+    QByteArray content = editor->getText(editor->textLength());
+    m_documentManager->setDocumentContent(docId, QString::fromUtf8(content));
+    
+    return m_documentManager->saveDocumentAs(docId, fileName);
+}
+
+void TabWidget::closeCurrentTab()
+{
+    int index = currentIndex();
+    if (index >= 0) {
+        closeTab(index);
+    }
+}
+
+bool TabWidget::closeTab(int index)
+{
+    if (index < 0 || index >= count()) {
+        return false;
+    }
+    
+    int docId = m_tabToDocumentId.value(index, -1);
+    if (docId == -1) {
+        return false;
+    }
+    
+    // 检查是否需要保存
+    if (m_documentManager->isDocumentModified(docId)) {
+        QString title = m_documentManager->getDocumentTitle(docId);
+        int ret = QMessageBox::question(this, "Save Changes",
+            QString("The document '%1' has been modified.\nDo you want to save your changes?").arg(title),
+            QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);
+        
+        if (ret == QMessageBox::Save) {
+            // 更新文档内容
+            SciEdit *editor = editorAt(index);
+            if (editor) {
+                QByteArray content = editor->getText(editor->textLength());
+                m_documentManager->setDocumentContent(docId, QString::fromUtf8(content));
+            }
+            
+            bool saved = false;
+            if (m_documentManager->isDocumentUntitled(docId)) {
+                QString fileName = QFileDialog::getSaveFileName(this, 
+                    "Save File", 
+                    title,
+                    "All Files (*.*)");
+                if (!fileName.isEmpty()) {
+                    saved = m_documentManager->saveDocumentAs(docId, fileName);
+                }
+            } else {
+                saved = m_documentManager->saveDocument(docId);
+            }
+            
+            if (!saved) {
+                return false; // 保存失败，不关闭标签页
+            }
+        } else if (ret == QMessageBox::Cancel) {
+            return false; // 取消关闭
+        }
+    }
+    
+    // 移除标签页
+    QWidget *widget = this->widget(index);
+    removeTab(index);
+    
+    // 清理映射关系
+    m_tabToDocumentId.remove(index);
+    m_documentIdToTab.remove(docId);
+    
+    // 更新其他标签页的索引映射
+    QHash<int, int> newTabToDocumentId;
+    QHash<int, int> newDocumentIdToTab;
+    
+    for (int i = 0; i < count(); ++i) {
+        int oldIndex = (i >= index) ? i + 1 : i;
+        int oldDocId = m_tabToDocumentId.value(oldIndex, -1);
+        if (oldDocId != -1) {
+            newTabToDocumentId[i] = oldDocId;
+            newDocumentIdToTab[oldDocId] = i;
+        }
+    }
+    
+    m_tabToDocumentId = newTabToDocumentId;
+    m_documentIdToTab = newDocumentIdToTab;
+    
+    // 清理编辑器和文档
+    if (m_editors.contains(docId)) {
+        SciEdit *editor = m_editors[docId];
+        disconnectEditorSignals(editor);
+        m_editors.remove(docId);
+    }
+    
+    m_documentManager->closeDocument(docId);
+    
+    if (widget) {
+        widget->deleteLater();
+    }
+    
+    // 如果没有标签页了，创建一个新的
+    if (count() == 0) {
+        newDocument();
+    }
+    
+    return true;
+}
+
+void TabWidget::closeAllTabs()
+{
+    while (count() > 0) {
+        closeTab(0);
+    }
+}
+
+SciEdit *TabWidget::currentEditor() const
+{
+    int docId = currentDocumentId();
+    return m_editors.value(docId, nullptr);
+}
+
+SciEdit *TabWidget::editorAt(int index) const
+{
+    int docId = m_tabToDocumentId.value(index, -1);
+    return m_editors.value(docId, nullptr);
+}
+
+int TabWidget::currentDocumentId() const
+{
+    int index = currentIndex();
+    return m_tabToDocumentId.value(index, -1);
+}
+
+int TabWidget::documentIdAt(int index) const
+{
+    return m_tabToDocumentId.value(index, -1);
+}
+
+void TabWidget::setCurrentTab(int index)
+{
+    if (index >= 0 && index < count()) {
+        setCurrentIndex(index);
+    }
+}
+
+int TabWidget::findTabByDocumentId(int docId) const
+{
+    return m_documentIdToTab.value(docId, -1);
+}
+
+void TabWidget::onCurrentChanged(int index)
+{
+    SciEdit *editor = editorAt(index);
+    emit currentEditorChanged(editor);
+}
+
+void TabWidget::onTabCloseRequested(int index)
+{
+    closeTab(index);
+}
+
+void TabWidget::onDocumentModified(int docId, bool modified)
+{
+    int tabIndex = findTabByDocumentId(docId);
+    if (tabIndex >= 0) {
+        updateTabTitle(tabIndex);
+    }
+}
+
+void TabWidget::onDocumentTitleChanged(int docId, const QString &title)
+{
+    int tabIndex = findTabByDocumentId(docId);
+    if (tabIndex >= 0) {
+        updateTabTitle(tabIndex);
+    }
+}
+
+void TabWidget::onEditorTextChanged()
+{
+    SciEdit *editor = qobject_cast<SciEdit*>(sender());
+    if (!editor) {
+        return;
+    }
+    
+    // 找到对应的文档ID
+    int docId = -1;
+    for (auto it = m_editors.begin(); it != m_editors.end(); ++it) {
+        if (it.value() == editor) {
+            docId = it.key();
+            break;
+        }
+    }
+    
+    if (docId != -1) {
+        QByteArray content = editor->getText(editor->textLength());
+        m_documentManager->setDocumentContent(docId, QString::fromUtf8(content));
+    }
+}
+
+SciEdit *TabWidget::createEditor()
+{
+    SciEdit *editor = new SciEdit(this);
+    connectEditorSignals(editor);
+    return editor;
+}
+
+void TabWidget::updateTabTitle(int tabIndex)
+{
+    int docId = m_tabToDocumentId.value(tabIndex, -1);
+    if (docId == -1) {
+        return;
+    }
+    
+    QString title = m_documentManager->getDocumentTitle(docId);
+    if (m_documentManager->isDocumentModified(docId)) {
+        title += " *";
+    }
+    
+    setTabText(tabIndex, title);
+}
+
+void TabWidget::connectEditorSignals(SciEdit *editor)
+{
+    if (editor) {
+        connect(editor, &SciEdit::textChanged, this, &TabWidget::onEditorTextChanged);
+    }
+}
+
+void TabWidget::disconnectEditorSignals(SciEdit *editor)
+{
+    if (editor) {
+        disconnect(editor, &SciEdit::textChanged, this, &TabWidget::onEditorTextChanged);
+    }
+}
\ No newline at end of file
diff --git a/tabwidget.h b/tabwidget.h
new file mode 100644
index 0000000..398016f
--- /dev/null
+++ b/tabwidget.h
@@ -0,0 +1,57 @@
+#pragma once
+
+#include <QTabWidget>
+#include <QHash>
+
+class SciEdit;
+class DocumentManager;
+
+class TabWidget : public QTabWidget
+{
+    Q_OBJECT
+
+public:
+    explicit TabWidget(DocumentManager *documentManager, QWidget *parent = nullptr);
+    ~TabWidget();
+
+    // 标签页管理
+    int newDocument();
+    int openDocument(const QString &filePath);
+    bool saveCurrentDocument();
+    bool saveCurrentDocumentAs();
+    void closeCurrentTab();
+    bool closeTab(int index);
+    void closeAllTabs();
+
+    // 获取当前编辑器和文档信息
+    SciEdit *currentEditor() const;
+    SciEdit *editorAt(int index) const;
+    int currentDocumentId() const;
+    int documentIdAt(int index) const;
+
+    // 标签页操作
+    void setCurrentTab(int index);
+    int findTabByDocumentId(int docId) const;
+
+signals:
+    void currentEditorChanged(SciEdit *editor);
+    void tabCloseRequested(int index);
+
+private slots:
+    void onCurrentChanged(int index);
+    void onTabCloseRequested(int index);
+    void onDocumentModified(int docId, bool modified);
+    void onDocumentTitleChanged(int docId, const QString &title);
+    void onEditorTextChanged();
+
+private:
+    DocumentManager *m_documentManager;
+    QHash<int, int> m_tabToDocumentId;  // tab index -> document id
+    QHash<int, int> m_documentIdToTab;  // document id -> tab index
+    QHash<int, SciEdit*> m_editors;     // document id -> editor
+
+    SciEdit *createEditor();
+    void updateTabTitle(int tabIndex);
+    void connectEditorSignals(SciEdit *editor);
+    void disconnectEditorSignals(SciEdit *editor);
+};
\ No newline at end of file