WPF停止可见性的 Storyboard 已更改

Question

我有一个带有 Storyboard的UserControl，并且我想在控件的“可见性”更改时停止动画。

我创建了一个Trigger来暂停动画并根据状态启动动画，但是我不断收到ArgumentException。

这是XAML:

<UserControl.Triggers>
    <EventTrigger RoutedEvent="FrameworkElement.Loaded">
        <BeginStoryboard x:Name="ProgressAnimation_BeginStoryboard" Storyboard="{StaticResource ProgressAnimation}"/>
    </EventTrigger>
    <Trigger Property="Control.Visibility" Value="Collapsed">
        <PauseStoryboard BeginStoryboardName="ProgressAnimation_BeginStoryboard" />
    </Trigger>
    <Trigger Property="Control.Visibility" Value="Visible">
        <ResumeStoryboard BeginStoryboardName="ProgressAnimation_BeginStoryboard" />
    </Trigger>
</UserControl.Triggers>

这是异常(exception):

The value "System.Windows.Media.Animation.PauseStoryboard" is not of type "System.Windows.SetterBase" and cannot be used in this generic collection. Parameter name: value

我将如何在XAML中做到这一点？

谢谢，
劳尔

Answer 1

您可以使用控制模板来做到这一点:

<ControlTemplate>
    ... Control stuff here

    <ControlTemplate.Triggers>
        <Trigger Property="Visibility" Value="Visible">
            <Trigger.EnterActions>
                <BeginStoryboard Storyboard="{StaticResource AnimationStoryboard}" x:Name="AnimationBeginStoryboard"/>
            </Trigger.EnterActions>
            <Trigger.ExitActions>
                <RemoveStoryboard BeginStoryboardName="AnimationBeginStoryboard"/>
            </Trigger.ExitActions>
        </Trigger>
    </ControlTemplate.Triggers>

</ControlTemplate>