マウスイベントが2回機能しない

Question

奇妙な問題が発生しました。私はキャンバスを持っており、複合体の構造を描画しました： ボーダー内のグリッド内にイメージがあります。 マイ・イメージは、動くためにアクティブなイメージです。

初めて構造をドラッグしてもうまく動作しますが、2回目は何も例外なく動作しますが、何も機能しません。私はマウスキャプチャの問題だと思われますが、私はそれについては理解できません。ここで

は私のイベントコードです：

bool captured = false; 
double x_shape, x_canvas, y_shape, y_canvas; 
double x_shape_Origine, y_shape_Origine; 
Border source = null; 


int CountZ = 10; 

private void shape_MoveButtonDown(object sender, MouseButtonEventArgs e) 
{ 
    /// AWFULLY SOURCE WAS null. I don't understand Why it was working the  
    /// first time 
    Mouse.Capture(source); 
    captured = true; 

    Image myImage = (Image)sender; 
    Grid outerGrid = (Grid)myImage.Parent; 
    source = (Border)outerGrid.Parent; 

    Canvas.SetZIndex(source, CountZ++); 
    x_shape = Canvas.GetLeft(source); 
    y_shape = Canvas.GetTop(source); 

    x_canvas = e.GetPosition(myCanvas).X; 
    y_canvas = e.GetPosition(myCanvas).Y; 

} 


private void shape_MoveMoving(object sender, MouseEventArgs e) 
{ 
    if (captured) 
    { 
     double x = e.GetPosition(myCanvas).X; 
     double y = e.GetPosition(myCanvas).Y; 
     x_shape += x - x_canvas; 
     Canvas.SetLeft(source, x_shape); 
     x_canvas = x; 
     y_shape += y - y_canvas; 
     Canvas.SetTop(source, y_shape); 
     y_canvas = y; 
    } 
} 

private void shape_MoveButtonUp(object sender, MouseButtonEventArgs e) 
{ 
    Mouse.Capture(null); 
    captured = false; 

} 

private void shape_MouseEnter(object sender, MouseEventArgs e) 
{ 
    if (!captured) 
    { 
     Border inner = (Border)sender; 
     Grid parentInner = (Grid)inner.Parent; 

     parentInner.Children[0].Visibility = Visibility.Visible; 
     parentInner.Children[2].Visibility = Visibility.Visible; 
     parentInner.Children[5].Visibility = Visibility.Visible; 
     parentInner.Children[6].Visibility = Visibility.Visible; 
     parentInner.Children[8].Visibility = Visibility.Visible; 

     parentInner.Background = new SolidColorBrush(Colors.Red); 
    } 
} 

private void shape_MouseLeave(object sender, MouseEventArgs e) 
{ 
    if (!captured) 
    { 
     Grid outer = (Grid)sender; 

     outer.Children[0].Visibility = Visibility.Hidden; 
     outer.Children[2].Visibility = Visibility.Hidden; 
     outer.Children[5].Visibility = Visibility.Hidden; 
     outer.Children[6].Visibility = Visibility.Hidden; 
     outer.Children[8].Visibility = Visibility.Hidden; 

     outer.Background = null; 
    } 
} 

は、私はWPFとSilverlightとD & Dのための完全なサンプルを持っていた、それはあなた

Answer 1

ために意味をなすことを願っています。ここで完全なコードは、それが助けて欲しい。

class MyWnd : Window 
{  
    public MyWnd() 
    { 
     var c = new Canvas(); 
     c.Background = new SolidColorBrush(Colors.White); 

     var rect = new Rectangle { Fill = new SolidColorBrush(Colors.Red), Width = 20, Height = 20 }; 
     c.Children.Add(rect); 

     this.Content = c; 

     Canvas.SetLeft(rect, 0); 
     Canvas.SetTop(rect, 0); 

     rect.MouseLeftButtonDown+=Handle_MouseDown; 
     rect.MouseLeftButtonUp+=Handle_MouseUp; 
     rect.MouseMove+=Handle_MouseMove; 
    } 


    bool isMouseCaptured; 
    double mouseVerticalPosition; 
    double mouseHorizontalPosition; 

    public void Handle_MouseDown(object sender, MouseEventArgs args) 
    { 
     var item = sender as FrameworkElement; 
     mouseVerticalPosition = args.GetPosition(null).Y; 
     mouseHorizontalPosition = args.GetPosition(null).X; 
     isMouseCaptured = true; 
     item.CaptureMouse(); 
    } 

    public void Handle_MouseMove(object sender, MouseEventArgs args) 
    { 
     var item = sender as FrameworkElement; 
     if (isMouseCaptured) 
     { 

      // Calculate the current position of the object. 
      double deltaV = args.GetPosition(null).Y - mouseVerticalPosition; 
      double deltaH = args.GetPosition(null).X - mouseHorizontalPosition; 
      double newTop = deltaV + (double)item.GetValue(Canvas.TopProperty); 
      double newLeft = deltaH + (double)item.GetValue(Canvas.LeftProperty); 

      // Set new position of object. 
      item.SetValue(Canvas.TopProperty, newTop); 
      item.SetValue(Canvas.LeftProperty, newLeft); 

      // Update position global variables. 
      mouseVerticalPosition = args.GetPosition(null).Y; 
      mouseHorizontalPosition = args.GetPosition(null).X; 
     } 
    } 

    public void Handle_MouseUp(object sender, MouseEventArgs args) 
    { 
     var item = sender as FrameworkElement; 
     isMouseCaptured = false; 
     item.ReleaseMouseCapture(); 
     mouseVerticalPosition = -1; 
     mouseHorizontalPosition = -1; 
    } 
} 

void Main() 
{ 
    var wnd = new MyWnd(); 
    wnd.ShowDialog(); 
}