c# - WPF 动画性能随时间下降

Question

我有两个动画:

    <Storyboard x:Key="ChangeLayout">
        <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="currentContent">
            <EasingDoubleKeyFrame KeyTime="0:0:0.0" Value="900"/>
            <EasingDoubleKeyFrame KeyTime="0:0:0.2" Value="0">
                <EasingDoubleKeyFrame.EasingFunction>
                    <CircleEase EasingMode="EaseInOut"/>
                </EasingDoubleKeyFrame.EasingFunction>
            </EasingDoubleKeyFrame>
        </DoubleAnimationUsingKeyFrames>
    </Storyboard>
    <Storyboard x:Key="HideLayout">
        <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="currentContent">
            <EasingDoubleKeyFrame KeyTime="0:0:0.2" Value="-900">
                <EasingDoubleKeyFrame.EasingFunction>
                    <CircleEase EasingMode="EaseInOut"/>
                </EasingDoubleKeyFrame.EasingFunction>
            </EasingDoubleKeyFrame>
        </DoubleAnimationUsingKeyFrames>
    </Storyboard>

以及开始它们的代码:

private void btnUser_Click(object sender, RoutedEventArgs e)
    {
        if (currentContent.Content != null)
            if (currentContent.Content.GetType() == typeof(Layouts.User))
                return;
        ((hl.Children[0] as DoubleAnimationUsingKeyFrames).KeyFrames[0] as EasingDoubleKeyFrame).Value = -this.ActualWidth;
        hl.Completed += (_sender, _e) =>
        {
            currentContent.Content = new Layouts.User();
            cl.Completed += (ssender, ee) =>
                {
                    btnMusic.Opacity = 0.5;
                    btnUser.Opacity = 0.9;
                };
            cl.Begin();
        };
        hl.Begin();
    }
    private void btnMusic_Click(object sender, RoutedEventArgs e)
    {
        if (currentContent.Content != null)
            if (currentContent.Content.GetType() == typeof(Layouts.Music))
                return;
        ((hl.Children[0] as DoubleAnimationUsingKeyFrames).KeyFrames[0] as EasingDoubleKeyFrame).Value = -this.ActualWidth;
        hl.Completed += (_sender, _e) =>
            {
                if (Layouts.Music.CurrentMusic == null)
                {
                    Layouts.Music.CurrentMusic = new Layouts.Music();
                    Layouts.Music.CurrentMusic.GetMusic();
                }
                currentContent.Content = Layouts.Music.CurrentMusic;
                cl.Completed += (ssender, ee) =>
                    {
                        btnUser.Opacity = 0.5;
                        btnMusic.Opacity = 0.8;
                    };

                cl.Begin();
            };
        hl.Begin();
    }

在用户和音乐内容之间切换几次后，ChangeLayout 动画开始非常缓慢且滞后，根据 WPF Performance Suite FPS 动画，切换后动画从 500 + 下降到最大值 4eh ...找不到任何解决方案 =(

对不起我的英语，我正在学习。

Answer 1

您是在每次单击按钮时添加事件处理程序，而不是删除它们。

hl.Completed += (_sender, _e) =>
{
};

在两个按钮处理程序中。这既会占用资源，又意味着每次单击按钮都会多次调用代码。

解决方案是将设置的处理程序移动到按钮点击的外部，或者在完成后删除处理程序。在后一种情况下，您必须将事件处理程序代码移动到一个单独的方法中，这样您就可以这样做:

hl.Completed += MyEventHandler;

然后:

private void MyEventHandler(object sender, EventArgs e)
{
    // Do stuff

    hl.Completed -= MyEventHandler;
}

虽然这意味着 hl 必须对两种方法都可见。