c# - EventTrigger RoutedEvent 未使用自定义事件触发

Question

我正在尝试在触发自定义路由事件(由我定义)时触发 Storyboard播放。该事件称为 CustomTest 并在 MyControl 中定义。

虽然正在触发事件，但触发器并未播放 Storyboard 。

XAML:

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:gear="clr-namespace:GearWPF"
    x:Class="GearWPF.MyControl"
    x:Name="UserControl">

...

    <Grid x:Name="LayoutRoot" Background="#00000000">
        <Grid.Triggers>
            <EventTrigger RoutedEvent="gear:MyControl.CustomTest"> <!-- My custom event. -->
                <BeginStoryboard Storyboard="{StaticResource MyStoryBoard}"/>
            </EventTrigger>
        </Grid.Triggers>
    </Grid>

C#:

namespace GearWPF
{
    /// <summary>
    /// Interaction logic for MyControl.xaml
    /// </summary>
    public partial class MyControl: UserControl
    {

        // Create a custom routed event by first registering a RoutedEventID 
        // This event uses the bubbling routing strategy 
        public static readonly RoutedEvent CustomTestEvent = EventManager.RegisterRoutedEvent("CustomTest", RoutingStrategy.Bubbling, typeof(RoutedEventHandler), typeof(MyControl));

        // Provide CLR accessors for the event 
        public event RoutedEventHandler CustomTest
        {
            add { AddHandler(CustomTestEvent, value); }
            remove { RemoveHandler(CustomTestEvent, value); }
        }

        public MyControl()
        {
            this.InitializeComponent();
        }

        public void RaiseMyEvent()
        {
            RoutedEventArgs newEventArgs = new RoutedEventArgs(CustomTestEvent);
            RaiseEvent(newEventArgs);
        }
    }
}

我已经验证了 RaiseMyEvent 在我期望的时候被调用了。使用 Snoop，我可以看到事件一直在我的控制之下(处理的是“False”)。但是，触发器实际上并未启动 Storyboard。

我还更改了触发器以使用现有事件，当我这样做时， Storyboard 被触发。这让我相信它是特定于我的路由事件 CustomTest 的东西。

    <Grid x:Name="LayoutRoot" Background="#00000000">
        <Grid.Triggers>
            <EventTrigger RoutedEvent="Mouse.MouseEnter"> <!-- This works! -->
                <BeginStoryboard Storyboard="{StaticResource MyStoryBoard}"/>
            </EventTrigger>
        </Grid.Triggers>
    </Grid>

Answer 1

问题是事件的级别过高。我正在将它发送到我的 CustomControl，但我真正想做的是将它发送到我的 Grid within CustomControl(因为事件只在根和源之间传递)。

    public void RaiseMyEvent()
    {
        RoutedEventArgs newEventArgs = new RoutedEventArgs(CustomTestEvent);
        LayoutRoot.RaiseEvent(newEventArgs); // This change fixes the issue.
    }