fix: memory leak of some controls. (#1482)

src/Shared/HandyControlDemo_Shared/UserControl/Controls/ImageBrowserDemoCtl.xaml

@@ -8,7 +8,7 @@
              xmlns:hc="https://handyorg.github.io/handycontrol">
     <hc:TransitioningContentControl>
         <StackPanel Margin="32">
-            <hc:ImageViewer Background="{DynamicResource SecondaryRegionBrush}" MaxWidth="600" Height="330" ImageSource="/HandyControlDemo;component/Resources/Img/1.jpg"/>
+            <hc:ImageViewer x:Name="ImageViewerDemo" Background="{DynamicResource SecondaryRegionBrush}" MaxWidth="600" Height="330" ImageSource="/HandyControlDemo;component/Resources/Img/1.jpg"/>
             <Button Margin="0,32,0,0" Command="{Binding OpenImgCmd}" Content="{ex:Lang Key={x:Static langs:LangKeys.OpenImageBrowser}}" Style="{StaticResource ButtonPrimary}" HorizontalAlignment="Center"/>
         </StackPanel>
     </hc:TransitioningContentControl>

src/Shared/HandyControlDemo_Shared/UserControl/Controls/ImageBrowserDemoCtl.xaml.cs

@@ -1,10 +1,17 @@
 
+using System;
+
 namespace HandyControlDemo.UserControl;
 
-public partial class ImageBrowserDemoCtl
+public partial class ImageBrowserDemoCtl : IDisposable
 {
     public ImageBrowserDemoCtl()
     {
         InitializeComponent();
     }
+
+    public void Dispose()
+    {
+        ImageViewerDemo.Dispose();
+    }
 }

src/Shared/HandyControl_Shared/Controls/Image/ImageViewer.cs

@@ -23,7 +23,7 @@ namespace HandyControl.Controls;
 [TemplatePart(Name = ElementBorderMove, Type = typeof(Border))]
 [TemplatePart(Name = ElementBorderBottom, Type = typeof(Border))]
 [TemplatePart(Name = ElementImageMain, Type = typeof(Image))]
-public class ImageViewer : Control
+public class ImageViewer : Control, IDisposable
 {
     #region Constants
 
@@ -167,6 +167,8 @@ public class ImageViewer : Control
 
     private ImageBrowser _imageBrowser;
 
+    private bool _isDisposed;
+
     #endregion Data
 
     #region ctor
@@ -989,4 +991,25 @@ public class ImageViewer : Control
             }
         }
     }
+
+    protected virtual void Dispose(bool disposing)
+    {
+        if (!_isDisposed)
+        {
+            if (disposing)
+            {
+                ImageSource = null;
+                _imageMain.Source = null;
+                _imageMain.UpdateLayout();
+            }
+
+            _isDisposed = true;
+        }
+    }
+
+    public void Dispose()
+    {
+        Dispose(disposing: true);
+        GC.SuppressFinalize(this);
+    }
 }

src/Shared/HandyControl_Shared/Controls/Window/ImageBrowser.cs

@@ -1,4 +1,5 @@
 using System;
+using System.ComponentModel;
 using System.IO;
 using System.Windows;
 using System.Windows.Controls;
@@ -110,6 +111,12 @@ public class ImageBrowser : Window
         }
     }
 
+    protected override void OnClosing(CancelEventArgs e)
+    {
+        _imageViewer?.Dispose();
+        base.OnClosing(e);
+    }
+
     private void ButtonClose_OnClick(object sender, RoutedEventArgs e) => Close();
 
     private void PanelTopOnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)