通过拖放移动 Canvas 上的控件

Question

我在 canvas 上放置了文本块。我使用以下代码更改鼠标拖动的位置：

   protected bool isDragging;
   private Point clickPosition;

   private void txt_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
            isDragging = true;
            var draggableControl = sender as TextBlock;
            clickPosition = e.GetPosition(this);
            draggableControl.CaptureMouse();
    }

    private void txt_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        isDragging = false;
        var draggable = sender as TextBlock;
        draggable.ReleaseMouseCapture();
    }

    private void txt_MouseMove(object sender, MouseEventArgs e)
    {
        var draggableControl = sender as TextBlock;

        if (isDragging && draggableControl != null)
        {
            Point currentPosition = e.GetPosition(this.Parent as UIElement);

            var transform = draggableControl.RenderTransform as TranslateTransform;
            if (transform == null)
            {
                transform = new TranslateTransform();
                draggableControl.RenderTransform = transform;
            }

            transform.X = currentPosition.X - clickPosition.X;
            transform.Y = currentPosition.Y - clickPosition.Y;
        }
    }

我在这里想要的是获取文本块的新位置，保存它，下次加载应用程序时，控件应该占据新位置。我知道我的代码不会更改文本块的 Left & Top 属性，而是对其进行转换。因此，Left 和 Top 属性不会改变。我尝试将 Left 和 Top 属性设置为

            draggableControl.SetValue(Canvas.LeftProperty, transform.X);
            draggableControl.SetValue(Canvas.TopProperty, transform.Y);

但它也没有改变它。

如何才能达到预期效果？

Answer 1

您不能使用转换...只能使用

draggableControl.SetValue(Canvas.LeftProperty, X);
draggableControl.SetValue(Canvas.TopProperty, Y);

因为变换只影响渲染

通过拖放移动 Canvas 上的控件

Moving a Control on a Canvas on Drag & Drop

c#

wpf

wpf-controls