EventTrigger RoutedEvent未使用自定义事件触发

时间:2014-03-11 20:44:13

标签: c# wpf user-controls triggers routed-events

我试图在触发自定义路由事件(由我定义)时触发故事板。该事件称为CustomTest,在MyControl中定义。

虽然事件被触发,但触发器没有播放故事板。

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);
        }
    }
}

我已经确认在我期望它时调用RaiseMyEvent。使用Snoop,我可以看到事件正在一直到我的控制(处理的是#34; False&#34;)。但是,触发器实际上并没有启动故事板。

我还更改了Trigger以使用现有事件,当我这样做时,会触发故事板。这让我相信它是特定于我的路由事件CustomTest。

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

1 个答案:

答案 0 :(得分:2)

问题是该事件的升级程度太高了。我将它发送到我的CustomControl,但我真正想做的是将它发送到 CustomControl中的Grid (因为事件只在根和源之间)。

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