Update MW_TouchEvents.cs

Ink Canvas/MainWindow_cs/MW_TouchEvents.cs

@@ -798,7 +798,45 @@ namespace Ink_Canvas
             {
                 isMultiTouchTimerActive = false;
             }
-            
+
+
+            // 当手掌擦激活且所有触摸点都抬起时，恢复原编辑模式
+            if (isPalmEraserActive && dec.Count == 0)
+            {
+                LogHelper.WriteLogToFile($"Palm eraser recovery triggered - Touch points remaining: {dec.Count}");
+
+                // 恢复高光状态
+                drawingAttributes.IsHighlighter = palmEraserLastIsHighlighter;
+
+                // 恢复编辑模式
+                try
+                {
+                    if (inkCanvas.EditingMode == InkCanvasEditingMode.EraseByPoint)
+                    {
+                        // 根据之前的状态恢复
+                        switch (palmEraserLastEditingMode)
+                        {
+                            case InkCanvasEditingMode.Ink:
+                                PenIcon_Click(null, null);
+                                break;
+                            case InkCanvasEditingMode.Select:
+                                SymbolIconSelect_MouseUp(null, null);
+                                break;
+                            default:
+                                inkCanvas.EditingMode = palmEraserLastEditingMode;
+                                break;
+                        }
+
+                        LogHelper.WriteLogToFile($"Palm eraser recovered to mode: {palmEraserLastEditingMode}");
+                    }
+                }
+                catch (Exception ex)
+                {
+                    // 如果恢复失败，强制切换到批注模式
+                    LogHelper.WriteLogToFile($"Palm eraser recovery failed: {ex.Message}, forcing to Ink mode", LogHelper.LogType.Error);
+                    inkCanvas.EditingMode = InkCanvasEditingMode.Ink;
+                }
+
                 // 重置手掌擦状态
                 isPalmEraserActive = false;
 
@@ -972,6 +1010,7 @@ namespace Ink_Canvas
 
             if (dec.Count == 0 && (isSingleFingerDragMode || isInMultiTouchMode))
             {
+                ResetTouchStates();
                 return;
             }