在后面的代碼中在WPF中創建一個Blink動畫

Question

我想將Blink動畫應用於Canvas以便我在其上繪制的所有對象都會閃爍。

我使用下面的代碼有點成功，它更快地改變了Canvas的Opacity屬性來實現這個效果，但我對它不滿意。

我希望在我當前的代碼中沒有任何FadeOut/FadeIn的純閃爍。 我怎么能以正確的方式做到這一點？

var blinkAnimation = new DoubleAnimation
{
    From = 1,
    To = 0
};

var blinkStoryboard = new Storyboard
{
    Duration = TimeSpan.FromMilliseconds(500),
    RepeatBehavior = RepeatBehavior.Forever,
    AutoReverse = true
};

Storyboard.SetTarget(blinkAnimation, MyCanvas);
Storyboard.SetTargetProperty(blinkAnimation, new PropertyPath(OpacityProperty));

blinkStoryboard.Children.Add(blinkAnimation);
MyCanvas.BeginStoryboard(blinkStoryboard);

也許我可以使用VisibilityProperty來做到這一點，但我無法做到。

Answer 1

您可以使用具有適當BeginTime的第二個動畫：

var switchOffAnimation = new DoubleAnimation
{
    To = 0,
    Duration = TimeSpan.Zero
};

var switchOnAnimation = new DoubleAnimation
{
    To = 1,
    Duration = TimeSpan.Zero,
    BeginTime = TimeSpan.FromSeconds(0.5)
};

var blinkStoryboard = new Storyboard
{
    Duration = TimeSpan.FromSeconds(1),
    RepeatBehavior = RepeatBehavior.Forever
};

Storyboard.SetTarget(switchOffAnimation, MyCanvas);
Storyboard.SetTargetProperty(switchOffAnimation, new PropertyPath(Canvas.OpacityProperty));
blinkStoryboard.Children.Add(switchOffAnimation);

Storyboard.SetTarget(switchOnAnimation, MyCanvas);
Storyboard.SetTargetProperty(switchOnAnimation, new PropertyPath(Canvas.OpacityProperty));
blinkStoryboard.Children.Add(switchOnAnimation);

MyCanvas.BeginStoryboard(blinkStoryboard);

Answer 2

如果您想要動畫的開/關狀態，可以將動畫更改為DoubleAnimationUsingKeyFrames

var blinkAnimation = new DoubleAnimationUsingKeyFrames();
blinkAnimation.KeyFrames.Add(new DiscreteDoubleKeyFrame(1, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(0))));
blinkAnimation.KeyFrames.Add(new DiscreteDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromMilliseconds(250))));

var blinkStoryboard = new Storyboard
{
    Duration = TimeSpan.FromMilliseconds(500),
    RepeatBehavior = RepeatBehavior.Forever,
};

Storyboard.SetTarget(blinkAnimation, MyCanvas);
Storyboard.SetTargetProperty(blinkAnimation, new PropertyPath(OpacityProperty));

blinkStoryboard.Children.Add(blinkAnimation);
blinkStoryboard.Begin();