try use pointer property for rail_uv

ballance_blender_plugin/__init__.py

@@ -77,6 +77,7 @@ class BALLANCE_MT_AddFloorMenu(bpy.types.Menu):
 
 classes = (
     preferences.BallanceBlenderPluginPreferences,
+    preferences.MyPropertyGroup,
     
     bm_import_export.BALLANCE_OT_import_bm,
     bm_import_export.BALLANCE_OT_export_bm,
@@ -117,6 +118,8 @@ def register():
 
     for cls in classes:
         bpy.utils.register_class(cls)
+
+    bpy.types.Scene.BallanceBlenderPluginProperty = bpy.props.PointerProperty(type=preferences.MyPropertyGroup)
         
     bpy.types.TOPBAR_MT_file_import.append(menu_func_bm_import)
     bpy.types.TOPBAR_MT_file_export.append(menu_func_bm_export)

ballance_blender_plugin/preferences.py

@@ -1,4 +1,12 @@
 import bpy
+import bpy.types
+
+class MyPropertyGroup(bpy.types.PropertyGroup):
+    material_picker : bpy.props.PointerProperty(
+        type=bpy.types.Material,
+        name="Material",
+        description="The material used for rail"
+    )
 
 class BallanceBlenderPluginPreferences(bpy.types.AddonPreferences):
     bl_idname = __package__

ballance_blender_plugin/rail_uv.py

@@ -1,5 +1,6 @@
 import bpy,bmesh
-from . import utils
+import bpy.types
+from . import utils, preferences
 
 class BALLANCE_OT_rail_uv(bpy.types.Operator):
     """Create a UV for rail"""
@@ -7,14 +8,42 @@ class BALLANCE_OT_rail_uv(bpy.types.Operator):
     bl_label = "Create Rail UV"
     bl_options = {'UNDO'}
 
+    uv_type: bpy.props.EnumProperty(
+        name="Type",
+        description="Define how to create UV",
+        items=(
+            ("POINT", "Point", "All UV will be created in a specific point"),
+            ("UNIFORM", "Uniform", "All UV will be created within 1x1"),
+            ("SCALE", "Scale", "Give a scale number to scale UV")
+            ),
+    )
+
+    uv_scale : bpy.props.FloatProperty(
+        name="Scale",
+        description="The scale of UV",
+        min=0.0,
+        default=1.0,
+    )
+
     @classmethod
     def poll(self, context):
         return check_rail_target()
 
+    def invoke(self, context, event):
+        wm = context.window_manager
+        return wm.invoke_props_dialog(self)
+
     def execute(self, context):
         create_rail_uv()
         return {'FINISHED'}
 
+    def draw(self, context):
+        layout = self.layout
+        layout.prop(self, "uv_type")
+        layout.prop(context.scene.BallanceBlenderPluginProperty, "material_picker")
+        if self.uv_type == 'SCALE':
+            layout.prop(self, "uv_scale")
+
 # ====================== method
 
 def check_rail_target():