TreeView ContextMenu not fired events - caliburn.micro

Question

TreeView ContextMenu not fired events (ContextMenu Opened event not fire), I'm trying Caliburn.Micro.Telerik convention not solved problem.
TreeViewItemTemplate
<HierarchicalDataTemplate x:Key="TreeViewItemTemplate" ItemsSource="{Binding Types}"
ItemTemplateSelector="{StaticResource NamespaceItemTemplateSelector}">
<StackPanel Orientation="Horizontal">
<Path
Data=""
Height="11.458" Margin="0,0,5,0" RenderTransformOrigin="0.5,0.5" Stretch="Fill"
UseLayoutRounding="False" Width="11.264">
<Path.Fill>
<SolidColorBrush Color="#FF333333">
<SolidColorBrush.RelativeTransform>
<MatrixTransform Matrix="Identity" />
</SolidColorBrush.RelativeTransform>
<SolidColorBrush.Transform>
<MatrixTransform Matrix="Identity" />
</SolidColorBrush.Transform>
</SolidColorBrush>
</Path.Fill>
<Path.RenderTransform>
<TransformGroup>
<ScaleTransform />
<SkewTransform />
<RotateTransform />
<TranslateTransform />
</TransformGroup>
</Path.RenderTransform>
</Path>
<TextBlock Text="{Binding Header}" Tag="{Binding DataContext, RelativeSource={RelativeSource Self}}">
<TextBlock.ContextMenu>
<ContextMenu cal:Action.TargetWithoutContext="{Binding RelativeSource={RelativeSource Self},Path=UIElement.Tag}" cal:Message.Attach="[Event Opened] = [Action Opened($dataContext)]" >
<MenuItem Header="NewChild" cal:Message.Attach="NewChild($datacontext)"/>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
</StackPanel>
TreeView
<TreeView x:Name="TreeView" ItemTemplate="{StaticResource TreeViewItemTemplate}" ItemsSource="{Binding Source}"/>

Answer 1

Before i tell you what was the problem i want to point out that the version of the code you uploaded is a bit different than the one you posted in your question.
OK, The problem lies exactly in this section of the template:
<TextBlock Text="{Binding Header}" Tag="{Binding DataContext, RelativeSource={RelativeSource Self}}">
<TextBlock.ContextMenu>
<ContextMenu cal:Action.TargetWithoutContext="{Binding RelativeSource={RelativeSource Self},Path=UIElement.Tag}" cal:Message.Attach="[Event Opened] = [Action Opened($dataContext)]" >
<MenuItem Header="NewChild" cal:Message.Attach="NewChild($datacontext)"/>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
To fix it you need to replace it with this modified version:
<TextBlock Text="{Binding Header}" Tag="{Binding DataContext, RelativeSource={RelativeSource Self}}">
<TextBlock.ContextMenu>
<ContextMenu cal:Action.TargetWithoutContext="{Binding RelativeSource={RelativeSource Self},Path=PlacementTarget.Tag}" cal:Message.Attach="[Event Opened] = [Action ContextMenuOpened($source)]">
<MenuItem Header="New" cal:Message.Attach="[Event Click] = [Action ClickMenuItem($source)]"/>
</ContextMenu>
</TextBlock.ContextMenu>
</TextBlock>
The problem was caused by three issues:
In the template and specifically in this line of code <ContextMenu cal:Action.TargetWithoutContext="{Binding RelativeSource={RelativeSource Self},Path=UIElement.Tag}" the Path=UIElement.Tag was causing a binding error because there is no property on type ContextMenu that is called UIElement. Instead you have to replace that with the PlacementTarget property which represents the element in the user interface on which the context menu was opened.
The second issue is that you were putting the methods that handle those events on the wrong class. They shouldn't be on the ShellViewModel because in the template you are setting the Action.Target to be the DataContext behind the TextBlock which is actually the NamespaceViewModel in your situation, so the methods should go on the NamespaceViewModel.
The third and final issue is that your methods had the wrong signature so they couldn't be found by Caliburn.Micro. What i mean is that you are declaring your ContextMenuOpened method like this: void ContextMenuOpened(sender args, RoutedEventArgs args); but in the template you are calling the method like this: [Action ContextMenuOpened($source)] which sends the method the FrameworkElement that caused the event (ContextMenu in this case), so you should change the method signature for this event to this: void ContextMenuOpened(ContextMenu source) or the more general void ContextMenuOpened(FrameworkElement source).
Summary:
Fix your template to use the PlacementTarget property.
Move your methods to NamespaceViewModel.
Fix your methods signatures.
Finally: If you want to know everything about actions and action messages and what parameters get passed to what then you should really read the documentation wiki about Actions.