testing undo (not working yet)

Author: unitycoder

PixelArtTool/MainWindow.xaml

@@ -39,6 +39,15 @@
 				<Slider x:Name="sliderOpacity" ToolTip="Opacity" HorizontalAlignment="Left" Margin="0,0,0,0" VerticalAlignment="Top" Width="50" Height="28" Value="255" Maximum="255" LargeChange="0" SmallChange="1" ValueChanged="OpacitySliderValueChanged"/>
 			</ToolBar>
 
+			<ToolBar Band="1" BandIndex="1" VerticalAlignment="Top">
+				<Button x:Name="btnUndo" ToolTip="Undo" Click="OnUndoButtonDown">
+					<Image Source="/Resources/Buttons/emptybutton.png" />
+				</Button>
+				<Button x:Name="btnRedo" ToolTip="Redo">
+					<Image Source="/Resources/Buttons/emptybutton.png" />
+				</Button>
+			</ToolBar>
+
 		</ToolBarTray>
 
 		<StatusBar Height="30" Margin="0,281,0,0" VerticalAlignment="Bottom">

PixelArtTool/MainWindow.xaml.cs

@@ -44,6 +44,10 @@ public partial class MainWindow : Window
         int prevX;
         int prevY;
 
+        // undo
+        const int maxUndoCount = 100;
+        int currentUndoIndex = 0;
+        WriteableBitmap[] undoBufferBitmap = new WriteableBitmap[maxUndoCount];
 
         public MainWindow()
         {
@@ -68,6 +72,7 @@ void Start()
             drawingImage.MouseRightButtonDown += new MouseButtonEventHandler(DrawingRightButtonDown);
             drawingImage.MouseDown += new MouseButtonEventHandler(DrawingMiddleButtonDown);
             w.MouseWheel += new MouseWheelEventHandler(drawingMouseWheel);
+            drawingImage.MouseUp += new MouseButtonEventHandler(DrawingMouseUp);
 
             // build palette
             paletteImage = imgPalette;
@@ -221,7 +226,6 @@ void DrawPixel(int x, int y)
 
             prevX = x;
             prevY = y;
-
         }
 
         void ErasePixel(MouseEventArgs e)
@@ -306,6 +310,14 @@ void DrawingLeftButtonDown(object sender, MouseButtonEventArgs e)
             DrawPixel(x, y);
         }
 
+        void DrawingMouseUp(object sender, MouseButtonEventArgs e)
+        {
+            // undo test
+            undoBufferBitmap[++currentUndoIndex] = canvasBitmap.Clone();
+            Console.WriteLine("save undo " + currentUndoIndex);
+        }
+
+
         void DrawingAreaMouseMoved(object sender, MouseEventArgs e)
         {
             // update mousepos info
@@ -421,5 +433,15 @@ private void OpacitySliderValueChanged(object sender, RoutedPropertyChangedEvent
             // ... Set Window Title.
             //this.Title = "Value: " + value.ToString("0.0") + "/" + slider.Maximum;
         }
+
+        private void OnUndoButtonDown(object sender, RoutedEventArgs e)
+        {
+            if (currentUndoIndex > 0)
+            {
+                canvasBitmap = undoBufferBitmap[--currentUndoIndex];
+                Console.WriteLine("restore undo " + currentUndoIndex);
+                imgCanvas.Source = canvasBitmap;
+            }
+        }
     } // class
 } // namespace