我已经创建了一个基本的微调器类型控件,它工作得相当好,但其中有大量重复的代码。除了两个属性之外,它基本上是一遍又一遍的相同元素,其中一个属性是情节提要的 BeginTime - 每一行只是无休止地重复其动画,但每一行在前一行之后开始 0.1 秒小波浪效应。
这是代码的总体思路:
<UserControl x:Class="MyNamespace.Spinner"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Grid>
<Rectangle Fill="Black" Opacity="0.5"
Width="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Grid}}, Path=Width}"
Height="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Grid}}, Path=Height}" />
<Line X1="9" X2="11" Y1="10" Y2="20">
<Line.Triggers>
<EventTrigger RoutedEvent="Line.Loaded">
<EventTrigger.Actions>
<BeginStoryboard>
<Storyboard RepeatBehavior="Forever" Duration="0:0:0.8"
BeginTime="0:0:0.1">
<DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
<LinearDoubleKeyFrame Value="0.5" KeyTime="0%" />
<LinearDoubleKeyFrame Value="1.0" KeyTime="12.5%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="75%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="100%" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Line.Triggers>
</Line>
<Line X1="14" X2="16" Y1="10" Y2="20">
<Line.Triggers>
<EventTrigger RoutedEvent="Line.Loaded">
<EventTrigger.Actions>
<BeginStoryboard>
<Storyboard RepeatBehavior="Forever" Duration="0:0:0.8"
BeginTime="0:0:0.2">
<DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
<LinearDoubleKeyFrame Value="0.5" KeyTime="0%" />
<LinearDoubleKeyFrame Value="1.0" KeyTime="12.5%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="75%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="100%" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Line.Triggers>
</Line>
<!-- And so on and so forth, 6 more times -->
</Grid>
</UserControl>
我不想把整件事都贴出来,那可能看起来太痛苦了,但你明白了。从 Line.Triggers 到 /Line.Triggers 的唯一变化是情节提要的 BeginTime。XAML 中有没有一种方法可以在 Line 中定义 BeginTime,然后在 Storyboard 中读取它,这样我就可以做一些更接近的事情:
<UserControl.Resources>
<!-- Try to read BeginTime from ancestral element -->
<Storyboard x:Key="myStoryboard" RepeatBehavior="Forever" Duration="0:0:0.8"
BeginTime="{Binding SomeSource, Property=StoryboardBeginTime}">
<DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
<LinearDoubleKeyFrame Value="0.5" KeyTime="0%" />
<LinearDoubleKeyFrame Value="1.0" KeyTime="12.5%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="75%" />
<LinearDoubleKeyFrame Value="0.5" KeyTime="100%" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</UserControl.Resources>
<!-- Try to send BeginTime to storyboard contained within -->
<Line Blah="blah" StoryboardBeginTime="0:0:0.1">
<Line.Triggers>
<EventTrigger>
<EventTrigger.Actions>
<BeginStoryboard Storyboard="{StaticResource myStoryboard}" />
</EventTrigger.Actions>
</EventTrigger>
</Line.Triggers>
</Line>
我似乎无法追踪是否有办法在 XAML 中执行此操作,从树上更高的元素向情节提要传递其属性之一的值。这种事情甚至可能吗,还是我应该在代码隐藏中做呢?如果我决定完全调整动画,这并不是现在做的最愉快的事情。
谢谢!