相关疑难解决方法(0)

我有以下示例代码,每次按下按钮时缩放:

XAML:

<Window x:Class="WpfApplication12.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">

    <Canvas x:Name="myCanvas">

        <Canvas.LayoutTransform>
            <ScaleTransform x:Name="myScaleTransform" />
        </Canvas.LayoutTransform> 

        <Button Content="Button" 
                Name="myButton" 
                Canvas.Left="50" 
                Canvas.Top="50" 
                Click="myButton_Click" />
    </Canvas>
</Window>

*的.cs

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void myButton_Click(object sender, RoutedEventArgs e)
    {
        Console.WriteLine("scale {0}, location: {1}", 
            myScaleTransform.ScaleX,
            myCanvas.PointToScreen(GetMyByttonLocation()));

        myScaleTransform.ScaleX =
            myScaleTransform.ScaleY =
            myScaleTransform.ScaleX + 1;

        Console.WriteLine("scale {0}, location: {1}",
            myScaleTransform.ScaleX,
            myCanvas.PointToScreen(GetMyByttonLocation()));
    }

    private Point GetMyByttonLocation()
    {
        return new Point(
            Canvas.GetLeft(myButton),
            Canvas.GetTop(myButton));
    }
}

输出是:

scale 1, location: …

我试图WPF在动画完成时为一些东西设置动画并运行一些其他操作。

另外，想避免动画完成回调机制，所以，我想出了一个解决方案，如下面的代码所示：

// Start one second of animation
...

// Pause for one second
Wait(this.Dispatcher, 1000);

// Continue and do some other stuff
...

现在，有趣的部分是Wait方法，它神奇地使我的代码中的阻塞暂停，但动画和 UI 保持正常、响应：

    public static void Wait(Dispatcher Dispatcher, int Milliseconds)
    {
        var Frame = new DispatcherFrame();
        ThreadPool.QueueUserWorkItem(State =>
        {
            Thread.Sleep(Milliseconds);
            Frame.Continue = false;
        });
        Dispatcher.PushFrame(Frame);
    }

我已经阅读了有关文档和几篇文章，DispatcherFrame但我仍然无法弄清楚幕后真正发生了什么，我需要澄清一下这种结构是如何PushFrame真正起作用的。