How To: RadMenuItem + ContainerBinding + CommandParameter as object?

[Rob]

Hello all,

I have a datagrid that lists a bunch of people and a context menu to perform some actions on those people - I'm using commands.

My context menu looks like this:
    
*
   -Add To Policy
          -Policy1   
          -Policy2
          -Policy3
   -Delete
   -Open
   -Blah Blah Blah

My problem is this.  When adding a person to a policy, I need to pass both the datagridrowcontext (a person) and the policy (a policy) to the command via containerbindings as a CommandParameter.

<telerik:HierarchicalDataTemplate x:Key="mnuPolicyTemplateContextMenu">
   <telerik:ContainerBinding.ContainerBindings>
      <telerik:ContainerBindingCollection>
         <telerik:ContainerBinding PropertyName="Command" Binding="{Binding Path=AddResourceToPolicyCommand, Source={StaticResource VMProxy}}" />
         <telerik:ContainerBinding PropertyName="CommandParameter">
            <telerik:ContainerBinding.Binding>
               <ps:AddResourceToPolicyCommandParameter Person="{Binding *datagridrow*}" Policy="{Binding *policy*}" />
            </telerik:ContainerBinding.Binding>
      </telerik:ContainerBinding>
   </telerik:ContainerBinding.ContainerBindings>
   <TextBlock Text="{Binding Name}" />
</telerik:HierarchicalDataTemplate>

1. How can I get a reference back to the datagridrow datacontext object (the person)?
2. Can I pass in an object like "ps:AddResourceToPolicyCommandParameter" with those parameters once I retrieve them?

[Rob]

I've answered question 1 --- 

<telerik:ContainerBinding PropertyName="CommandParameter">
    <telerik:ContainerBinding.Binding>
        <projectsecurity:AddResourceToPolicyCommandParameter ProjectResource="{Binding Path=Menu.DataContext, RelativeSource={RelativeSource Self}, Mode=TwoWay}" Policy="{Binding ., Mode=TwoWay}" />
    </telerik:ContainerBinding.Binding>
</telerik:ContainerBinding>

Now for question 2...  why do I get an System.Windows.Markup.XamlParseException when trying to create this object?

[Ivo]

Hi,

I think what you are trying cannot be achieved this way. I would suggest you to use the RadContextMenu's opened event. There you can get the clicked element.

private void RadContextMenu_Opened( object sender, RoutedEventArgs e )

{

    var item = this.radContextMenu.GetClickedElement<DataGridRow>();
     //update the last selected item into your viewModel


}

Then you will have to pass only one value into your CommandParameter which will be a lot easier task. I understand you don't want to use code behind, but into this case this will be the recommended solution.

Kind regards, Ivo
the Telerik team

[Rob]

Sorry, I should have closed this...

<telerik:ContainerBinding PropertyName="CommandParameter" Binding="{Binding ., RelativeSource={RelativeSource Self}, Converter={StaticResource AddResourceToPolicyCommandParameterConverter}}" />

I figured out a way around it by binding to the RadMenuItem, and creating the parameter object in a converter...  Still hacky, but much better than code behind.