在代码中使用GeometryGroup创建组合形状

Question

我需要一些帮助来使用我的代码。 combineShape.Freeze（）函数看起来不太好。

在这种情况下，我有两个单选按钮，名为rbtPoint和rbtLine。当我单击rbtPoint并单击画布时，它将创建一个点，现在我必须在画布中创建2个点（ellipse1，ellipse2），在此步骤中，我已经可以在画布周围拖动Point（椭圆1或椭圆2） 。然后当我点击rbtLine然后点击第一个点（ellipse1）它会将点的颜色从红色变为蓝色，然后当我再次点击第二个点（椭圆2）时，它也会将颜色变成红色，并且它会创建从ellipse1到ellipse2的连接蓝线。 之后，使用GeometryGroup（）函数将直线和2个点合并为1个形状。我看到的代码从这个链接：

http://stackoverflow.com/questions/16417950/combining-linegeometry-with-ellipsegeometry-in-code-not-xaml

这里是我的代码来创建功能：

 
private void myCanvas_MouseDown(object sender, MouseButtonEventArgs e) 
     { 
      mouseDown = true; 
      initialPoint = e.GetPosition(sender as IInputElement); 

      if (rbtPoint.IsChecked == true) 
      { 
       if (e.OriginalSource is Ellipse) 
       { 
        captured = true; 
        shapePoint = e.GetPosition(sender as IInputElement); 
        clickedEllipse = (Ellipse)e.OriginalSource; 
        uielement = (UIElement)e.OriginalSource; 
       } 
       else 
       { 
        shapeEllipse = new Ellipse(); 
        (shapeEllipse as Ellipse).Width = 30; 
        (shapeEllipse as Ellipse).Height = 30; 
        (shapeEllipse as Ellipse).StrokeThickness = 5; 
        (shapeEllipse as Ellipse).Fill = Brushes.Red; 
        Canvas.SetLeft(shapeEllipse, initialPoint.X); 
        Canvas.SetTop(shapeEllipse, initialPoint.Y); 
        myCanvas.Children.Add(shapeEllipse); 
       } 
      } 
     }    

 
private void myCanvas_MouseUp(object sender, MouseButtonEventArgs e) 
     { 
      Mouse.Capture(null); 
      captured = false; 
      mouseDown = false; 
      if (rbtLine.IsChecked == true) 
      { 
       if (e.OriginalSource is Ellipse) 
       { 
        captured = true; 
        initialPoint = e.GetPosition(sender as IInputElement); 
        clickedEllipse = (Ellipse)e.OriginalSource; 
        uielement = (UIElement)e.OriginalSource; 
        poin = e.MouseDevice.GetPosition(uielement); 
        clickedEllipse.Fill = Brushes.Blue; 
        if (firstpoint.X != 0 && firstpoint.Y != 0) 
        { 
         lineEndPoint = initialPoint; 
        } 
        else 
        { 
         firstpoint = initialPoint; 
        } 
       } 

       if (lineEndPoint.X != 0 && lineEndPoint.Y != 0) 
       { 
        Point p = e.GetPosition(sender as IInputElement); 
        shapeLine = new Line(); 
        (shapeLine as Line).X1 = firstpoint.X; 
        (shapeLine as Line).Y1 = firstpoint.Y; 
        (shapeLine as Line).X2 = lineEndPoint.X; 
        (shapeLine as Line).Y2 = lineEndPoint.Y; 
        (shapeLine as Line).Stroke = Brushes.Blue; 
        (shapeLine as Line).StrokeThickness = 5; 
        //(shape as Line).Fill = Brushes.Blue; 
        //Canvas.SetLeft(shape, firstpoint.X); 
        //Canvas.SetTop(shape, firstpoint.Y); 
        myCanvas.Children.Add(shapeLine); 
        lineCreated = true; 

        var ellipse1 = new EllipseGeometry(firstpoint, firstpoint.X, firstpoint.Y); 
        var ellipse2 = new EllipseGeometry(lineEndPoint, lineEndPoint.X, lineEndPoint.Y); 
        var line = new LineGeometry(this.firstpoint, this.lineEndPoint); 

        GeometryGroup combinedShape = new GeometryGroup(); 
        combinedShape.Children.Add(ellipse1); 
        combinedShape.Children.Add(ellipse2); 
        combinedShape.Children.Add(line); 

        combinedShape.Freeze(); 
       } 

      } 
     } 

后，我跑combinedShape.Freeze（）函数，当我再次点击一个点并拖动它，它只会移动点击点，而没有其他点和线跟随我的鼠标移动。

如何解决这个问题？我发现许多相关的文章，但他们中的大多数人在XAML中执行代码而不是代码隐藏。或者还有其他解决方法吗？ 我需要建议，对于这个问题，

感谢你的帮助，代码大师..

Fikri

Answer 1

听起来像你对我真的不希望冻结它。 Freeze（）使几何体不可更改，这正是它不改变的原因。

唯一的其他选择是做类似clone（）的冻结几何体，然后删除冻结的几何体。

private void myCanvas_MouseDown(object sender, MouseButtonEventArgs e) 
     { 
      mouseDown = true; 
      initialPoint = e.GetPosition(sender as IInputElement); 

      if (rbtPoint.IsChecked == true) 
      { 
       if (e.OriginalSource is Ellipse) 
       { 
        captured = true; 
        shapePoint = e.GetPosition(sender as IInputElement); 
        var frozen = (Ellipse)e.OriginalSource; 
        clickedEllipse = frozen.Clone(); 
        myCanvas.Children.Remove(frozen); 
        myCanvas.Children.Add(clickedEllipse); 
        uielement = (UIElement)clickedEllipse; 
       } 
       else