Question

I have a usercontrol with a Tree inside it with, the command property binds to the DataType and not the DataContext.

How can I redirect the binding to go to the DataContext and Not the DataType ? Also Out of curiosity how would I bind to the UserControl’s DataContext instead of the Tree’s DataContext ?

Here is the code in question:

<HierarchicalDataTemplate 
            DataType="{x:Type viewModel:UsersViewModel}" 
            ItemsSource="{Binding Children}"
            >
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding UserName}">
                    <TextBlock.ContextMenu>
                            <ContextMenu>
                                <MenuItem Header="Edit" Command="{Binding EditCommand}" CommandParameter="{Binding UserName}"/>
                                <MenuItem Header="Delete"/>
                            </ContextMenu>
                        </TextBlock.ContextMenu>
                </TextBlock>
            </StackPanel>
        </HierarchicalDataTemplate>

It seems to bind to the UsersViewModel and Not the DataContext(AllUsersViewModel).

This is the entire piece of XAML Just in case:

 <Grid Width="150">
<TreeView ItemsSource="{Binding Users}" DataContext="{Binding allUsersViewModel}">
    <TreeView.ItemContainerStyle>
        <!-- 
    This Style binds a TreeViewItem to a TreeViewItemViewModel. 
    -->
        <Style TargetType="{x:Type TreeViewItem}">
            <Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}" />
            <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
            <Setter Property="FontWeight" Value="Normal" />
            <Style.Triggers>
                <Trigger Property="IsSelected" Value="True">
                    <Setter Property="FontWeight" Value="Bold" />
                </Trigger>
            </Style.Triggers>
        </Style>
    </TreeView.ItemContainerStyle>

    <TreeView.Resources>    
        <ContextMenu x:Key="CategoryMenu">
            <MenuItem Header="Add Subcategory" Command="New">
            </MenuItem>

            <MenuItem Header="Remove Category" Command="Delete">
            </MenuItem>
        </ContextMenu>

        <HierarchicalDataTemplate 
            DataType="{x:Type viewModel:UsersViewModel}" 
            ItemsSource="{Binding Children}"
            >
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding UserName}">
                    <TextBlock.ContextMenu>
                            <ContextMenu>
                                <MenuItem Header="Edit" Command="{Binding EditCommand}" CommandParameter="{Binding UserName}"/>
                                <MenuItem Header="Delete"/>
                            </ContextMenu>
                        </TextBlock.ContextMenu>
                </TextBlock>
            </StackPanel>
        </HierarchicalDataTemplate>

        <HierarchicalDataTemplate 
            DataType="{x:Type viewModel:PermissionCategoryViewModel}" 
            ItemsSource="{Binding Children}"
            >
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding PermissionCategoryName}" />
            </StackPanel>
        </HierarchicalDataTemplate>

        <DataTemplate DataType="{x:Type viewModel:PermissionViewModel}">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding PermissionName}" />
            </StackPanel>
        </DataTemplate>
    </TreeView.Resources>
</TreeView>
</Grid> 

Thanks for the Help!

EDIT

Well I tried a few things, but it didnt work out =(. Nothing Happens

I should have mentioned that my MainWindow Has the DataContext and the UserControl Inherits it by placing the UserControl Inside of it.

<Window.DataContext>
    <viewModel:MainViewModel/>
</Window.DataContext>

I tried these different things

Command="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:AllUsers}}, Path=DataContext.EditCommand}"

and

Command="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:MainWindow}}, Path=DataContext.EditCommand}"

and

Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:MainWindow}}, Path=DataContext.EditCommand}"

and

Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type local:AllUsers}}, Path=DataContext.EditCommand}"

Lastly

Command="{Binding PlacementTarget.DataContext.EditCommand, 
                      RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ContextMenu}}}"

Answer 1

You can use a RelativeSource binding to find the TreeView, then bind to it’s DataContext

Command="{Binding Path=DataContext.EditCommand,
    RelativeSource={RelativeSource AncestorType={x:Type TreeView}}}"

If you ever want to bind to your UserControl, you can use the same type of binding:

RelativeSource={RelativeSource AncestorType={x:Type local:MyUserControl}}

Note that RelativeSource bindings will return a reference to the UI object, not it’s DataContext, so if you want to bind to something in the DataContext you have to specify Path=DataContext.SomeValue