WPF Interaction Trigger MouseDoubleClick event not firing

Question

I have a MouseDoubleClick event in the following .xaml file which is not firing properly:

<Style TargetType="controls:Source" x:Key="{x:Type controls:Source}">
<Setter Property="Template">
  <Setter.Value>
    <ControlTemplate TargetType="controls:Source">
      <Border BorderThickness="0.8" CornerRadius="10" BorderBrush="{TemplateBinding Foreground}"
              d:DataContext="{d:DesignInstance d:Type=viewModels:SourceViewModel}">
        <Grid Style="{StaticResource ElementThatClipsToParentBordersStyle}">
          <Image Source="{Binding AttachedSource.Image, RelativeSource={RelativeSource TemplatedParent}}" Stretch="Fill" />

          <Border x:Name="Selection"
                  Opacity="0.3"
                  Background="{TemplateBinding Foreground}"
                  Visibility="Collapsed"
                  IsHitTestVisible="False"/>
        </Grid>

        <i:Interaction.Triggers>
          <i:EventTrigger EventName="MouseLeftButtonDown">
            <interactivity:InvokeCommandAction Command="{Binding DataContext.SelectionState.ClickSourceCommand, ElementName=SourcesControl}"
                                               CommandParameter="{Binding}" />
          </i:EventTrigger>

          <i:EventTrigger EventName="PreviewMouseLeftButtonDown">
            <interactivity:InvokeCommandAction Command="{Binding PreviewLeftClickCommand}" />
          </i:EventTrigger>

          <i:EventTrigger EventName="MouseMove">
            <interactivity:InvokeCommandAction Command="{Binding MouseMoveCommand}" />
          </i:EventTrigger>

          <i:EventTrigger EventName="MouseDoubleClick">
            <interactivity:InvokeCommandAction Command="{Binding SourceDoubleClickCommand}"
                                               CommandParameter="{Binding}" />
          </i:EventTrigger>
        </i:Interaction.Triggers>

      </Border>

      <ControlTemplate.Triggers>
        <Trigger Property="IsSelected" Value="True">
          <Setter TargetName="Selection" Property="Visibility" Value="Visible" />
        </Trigger>
      </ControlTemplate.Triggers>
    </ControlTemplate>
  </Setter.Value>
</Setter>

Every others event works just fine and as intended but the command bound to the MouseDoubleClick event is not executed.

The weird thing is that when I use another event such as MouseLeftButtonDown everything is working, so the problem does not seem to be connected to the excuted command but to the used event itself.

Of course I could work around this problem by using a simple MouseLeftButtonDown event and check for the time of the last click to identify a doubleclick but the built-in doubleclick event seems to be better way to go for me.

Does someone have an idea why the MouseDoubleClick event is not firing properly in this scenario?

Answer 1

Border does not have a MouseDoubleClick event, because it is not a control. There are a couple of ways of making a MouseDoubleClick available. See Why doesn't WPF border control have a mousedoubleclick event? .

A straightforward way is to wrap your border in a ContentControl which raises the MouseDoubleClick event (from http://blogs.microsoft.co.il/pavely/2011/08/03/wpf-tip-using-a-mousedoubleclick-event-where-none-exists/ ):

<ContentControl MouseDoubleClick="OnDoubleClick">
  <Border Margin="10" BorderBrush="Black" BorderThickness="2">
    <Grid Margin="4">
        <Rectangle Fill="Red" />
        <TextBlock Text="Hello" FontSize="15" />
    </Grid>
  </Border>
</ContentControl>