c# - 命令在我自定义的 UserControl 中内置的事件上不起作用/触发

Question

我正在开发这个 (MVVM) Windows 8.1 metro 应用程序，我正在使用我单独构建的 UserControl，这个 UserControl 有它自己的事件，我为它而建。

我的问题是:当我尝试在全局应用程序中对那些它们从不触发的命令使用命令时，尽管事件有效!

UserControl 及其事件:

public delegate void PlayClickedEventHandler(object sender, RoutedEventArgs e);
...
public event PlayClickedEventHandler PlayClicked;

PlayClicked 事件在 UserControl 中的按钮被点击时触发

private void PlayButton_OnClick(object sender, RoutedEventArgs e)
{
   if (PlayClicked != null)
   PlayClicked(this, e);
}

全局 Windows 8.1 MVVM 应用:

View :

<mediaPlayerControl:PlayerControl x:Name="UserControl">
    <interactivity:Interaction.Behaviors>
        <core:EventTriggerBehavior EventName="PlayClicked">
              <core:InvokeCommandAction Command="{Binding OnPlayClicked, Mode=TwoWay}"/>
    </core:EventTriggerBehavior>
    </interactivity:Interaction.Behaviors>
</mediaPlayerControl:PlayerControl>

View 模型:

public RelayCommand OnPlayClicked { get; set; }
    OnPlayClicked = new RelayCommand(() =>
                                    {
                                       //Stuff to do here that seem not to be done
                                    });

我是不是错过了什么？？

Answer 1

我想这可以解释它(来自 EventTriggerBehavior 上的文档)

The following events are supported:

(list of 11 events)

Consider implementing a custom behavior to respond to other events.

为什么不使用 EventTrigger反而？ (另请注意，“OnPlayClicked”绑定(bind)实际上应该是一种方式，尽管这不应该有所作为。)

<mediaPlayerControl:PlayerControl x:Name="UserControl">
    <interactivity:Interaction.Triggers>
        <uixaml:EventTrigger EventName="PlayClicked">
            <core:InvokeCommandAction Command="{Binding OnPlayClicked}"/>
        </uixaml:EventTrigger>
    </interactivity:Interaction.Triggers>
</mediaPlayerControl:PlayerControl>