当我在 WPF 中更改样式时故事板不会更改
Storyboard does not change when I change style in WPF
我想 运行 箭头图片 (png) 上的简单动画。箭头指向下方或上方，动画应该是波浪朝箭头指向的方向移动。
我使用 Image 控件并将两种样式之一分配给它。这些样式定义了故事板中要使用的图片和三个双动画。动画应该无条件地 运行，从图像创建的那一刻起，永远。其中一种样式是箭头向上，波浪向上移动（Trend_Rising），另一种样式是箭头向下，波浪向下移动（Trend_Falling).
以下是图像，样式位于从嵌入图像的 UserControl 引用的单独文件中。
<Image x:Name="TrendImg" Style="{DynamicResource Trend_Falling}" />
这是样式文件的内容：
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Style x:Key="Trend_Base" TargetType="Image">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising_Base" TargetType="Image" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="IsVisible" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling_Base" TargetType="Image" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="IsVisible" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Rising" TargetType="Image" BasedOn="{StaticResource Trend_Rising_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
</Style>
<Style x:Key="Trend_Falling" TargetType="Image" BasedOn="{StaticResource Trend_Falling_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
</Style>
</ResourceDictionary>
问题是，当我以编程方式更改样式时，动画并没有改变。例如，如果我启动应用程序（图像分配了 Trend_Falling 样式），向下箭头将显示为向下移动的波浪动画。但是当我在运行的时候把样式改成Trend_Rising的时候，箭头图片就变了，但是动画还是一样。
TrendImg.SetResourceReference(Control.StyleProperty, "Trend_Rising")
我做错了什么？我将不胜感激任何帮助。谢谢！
-- 编辑--
我创建了一个 ImageWithAnim class，它是 Image 的后代，并添加了一个布尔值 Animate 对它的依赖 属性。然后我将触发器附加到 属性 而不是 IsVisible。 True 启动情节提要，而 false 应该停止它，但它没有...当我将 Animate 设置为 false 时，会抛出一个异常，说明名称 RisingStoryboard 无法在命名空间 System.Windows.Style 中解析。我在 Whosebug 上找到了几篇帖子，根据这些帖子，这个例子应该可以工作（在那些声称它不会 :-) 的帖子中）。
所以...现在我不知道该怎么做。我将不胜感激任何帮助。谢谢！
这是修改后的 xaml:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Test="clr-namespace:StyleChangeTest">
<Style x:Key="Trend_Base" TargetType="Test:ImageWithAnim">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising_Base" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="RisingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
<Trigger Property="Animate" Value="False">
<Trigger.EnterActions>
<StopStoryboard BeginStoryboardName="RisingStoryboard" />
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling_Base" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="FallingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
<Trigger Property="Animate" Value="False">
<Trigger.EnterActions>
<StopStoryboard BeginStoryboardName="FallingStoryboard" />
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Rising" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Rising_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
</Style>
<Style x:Key="Trend_Falling" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Falling_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
</Style>
</ResourceDictionary>
这是 ImageWithAnim class:
Public Class ImageWithAnim
Inherits Image
Private Shared _animate As DependencyProperty = DependencyProperty.Register("Animate",
GetType(Boolean),
GetType(ImageWithAnim),
New PropertyMetadata(defaultValue:=False))
Public Shared ReadOnly Property AnimateProperty As DependencyProperty
Get
Return _animate
End Get
End Property
Public Property Animate() As Boolean
Get
Return CBool(GetValue(_animate))
End Get
Set(value As Boolean)
SetValue(_animate, value)
End Set
End Property
End Class
巧合的是，我刚刚找到了我自己的问题的答案。故事板的名称无法解析，因为它们是在基本样式中定义的。当我直接以我感兴趣的两种样式定义它们时，我可以按预期使用 ImageWithAnim 的 Animate 属性 来启动和停止它们, 无一例外。
因此，在更改图像样式时，我必须执行以下操作：
TrendImg.Animate = False
TrendImg.SetResourceReference(ImageWithAnim.StyleProperty, "Trend_Falling")
TrendImg.Animate = True
现在动画改好了，波浪动画按照箭头所指的方向移动，这就是我想要实现的。
这是更改后的样式：
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Test="clr-namespace:StyleChangeTest">
<Style x:Key="Trend_Base" TargetType="Test:ImageWithAnim">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="RisingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="RisingStoryboard" />
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="FallingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="FallingStoryboard" />
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
</ResourceDictionary>
并解释为什么我在开头将故事板置于基本样式中。问题是在我原来的应用程序中我有几个不同的箭头图片，只是不想重复情节提要定义。但是看来我不得不。
我想 运行 箭头图片 (png) 上的简单动画。箭头指向下方或上方，动画应该是波浪朝箭头指向的方向移动。
我使用 Image 控件并将两种样式之一分配给它。这些样式定义了故事板中要使用的图片和三个双动画。动画应该无条件地 运行，从图像创建的那一刻起，永远。其中一种样式是箭头向上，波浪向上移动（Trend_Rising），另一种样式是箭头向下，波浪向下移动（Trend_Falling).
以下是图像，样式位于从嵌入图像的 UserControl 引用的单独文件中。
<Image x:Name="TrendImg" Style="{DynamicResource Trend_Falling}" />
这是样式文件的内容：
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Style x:Key="Trend_Base" TargetType="Image">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising_Base" TargetType="Image" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="IsVisible" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling_Base" TargetType="Image" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="IsVisible" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Rising" TargetType="Image" BasedOn="{StaticResource Trend_Rising_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
</Style>
<Style x:Key="Trend_Falling" TargetType="Image" BasedOn="{StaticResource Trend_Falling_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
</Style>
</ResourceDictionary>
问题是，当我以编程方式更改样式时，动画并没有改变。例如，如果我启动应用程序（图像分配了 Trend_Falling 样式），向下箭头将显示为向下移动的波浪动画。但是当我在运行的时候把样式改成Trend_Rising的时候，箭头图片就变了，但是动画还是一样。
TrendImg.SetResourceReference(Control.StyleProperty, "Trend_Rising")
我做错了什么？我将不胜感激任何帮助。谢谢！
-- 编辑--
我创建了一个 ImageWithAnim class，它是 Image 的后代，并添加了一个布尔值 Animate 对它的依赖 属性。然后我将触发器附加到 属性 而不是 IsVisible。 True 启动情节提要，而 false 应该停止它，但它没有...当我将 Animate 设置为 false 时，会抛出一个异常，说明名称 RisingStoryboard 无法在命名空间 System.Windows.Style 中解析。我在 Whosebug 上找到了几篇帖子，根据这些帖子，这个例子应该可以工作（在那些声称它不会 :-) 的帖子中）。
所以...现在我不知道该怎么做。我将不胜感激任何帮助。谢谢！
这是修改后的 xaml:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Test="clr-namespace:StyleChangeTest">
<Style x:Key="Trend_Base" TargetType="Test:ImageWithAnim">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising_Base" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="RisingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
<Trigger Property="Animate" Value="False">
<Trigger.EnterActions>
<StopStoryboard BeginStoryboardName="RisingStoryboard" />
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling_Base" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="FallingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
<Trigger Property="Animate" Value="False">
<Trigger.EnterActions>
<StopStoryboard BeginStoryboardName="FallingStoryboard" />
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Rising" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Rising_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
</Style>
<Style x:Key="Trend_Falling" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Falling_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
</Style>
</ResourceDictionary>
这是 ImageWithAnim class:
Public Class ImageWithAnim
Inherits Image
Private Shared _animate As DependencyProperty = DependencyProperty.Register("Animate",
GetType(Boolean),
GetType(ImageWithAnim),
New PropertyMetadata(defaultValue:=False))
Public Shared ReadOnly Property AnimateProperty As DependencyProperty
Get
Return _animate
End Get
End Property
Public Property Animate() As Boolean
Get
Return CBool(GetValue(_animate))
End Get
Set(value As Boolean)
SetValue(_animate, value)
End Set
End Property
End Class
巧合的是，我刚刚找到了我自己的问题的答案。故事板的名称无法解析，因为它们是在基本样式中定义的。当我直接以我感兴趣的两种样式定义它们时，我可以按预期使用 ImageWithAnim 的 Animate 属性 来启动和停止它们, 无一例外。
因此，在更改图像样式时，我必须执行以下操作：
TrendImg.Animate = False
TrendImg.SetResourceReference(ImageWithAnim.StyleProperty, "Trend_Falling")
TrendImg.Animate = True
现在动画改好了，波浪动画按照箭头所指的方向移动，这就是我想要实现的。
这是更改后的样式：
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Test="clr-namespace:StyleChangeTest">
<Style x:Key="Trend_Base" TargetType="Test:ImageWithAnim">
<Setter Property="OpacityMask">
<Setter.Value>
<LinearGradientBrush StartPoint="0,1" EndPoint="0,0">
<GradientStop Color="Black" />
<GradientStop Color="Transparent" />
<GradientStop Color="Black" />
</LinearGradientBrush>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="Trend_Rising" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_rising.png" />
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="RisingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="-0.1" To="0.9" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="0.0" To="1.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="0.1" To="1.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="RisingStoryboard" />
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="Trend_Falling" TargetType="Test:ImageWithAnim" BasedOn="{StaticResource Trend_Base}">
<Setter Property="Height" Value="16" />
<Setter Property="Source" Value="trend_falling.png" />
<Style.Triggers>
<Trigger Property="Animate" Value="True">
<Trigger.EnterActions>
<BeginStoryboard x:Name="FallingStoryboard">
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[0].Offset" From="0.9" To="-0.1" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[1].Offset" From="1.0" To="0.0" Duration="0:0:2" RepeatBehavior="Forever" />
<DoubleAnimation Storyboard.TargetProperty="OpacityMask.GradientStops[2].Offset" From="1.1" To="0.1" Duration="0:0:2" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="FallingStoryboard" />
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
</ResourceDictionary>
并解释为什么我在开头将故事板置于基本样式中。问题是在我原来的应用程序中我有几个不同的箭头图片，只是不想重复情节提要定义。但是看来我不得不。