Silverlight 4: How to find source UI element from contextmenu's menuitem_click?

Question

I have a datagrid and I added silverlight 4 toolkit contextmenu to textbox in datagrid as follows. When users right click on the textbox, contextmenu is being displayed. When users click the menu item with Header "Test", "MenuItem_Click" is getting executed. Now I want to access the textbox from the MenuItem_Click and modify its properties like background etc. Is there anyway to find textbox element(which is contextmenu's parent) from MenuItem_Click event?

It appears to me that I am missing something very simple.

<my:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
    <TextBox Text="{Binding AcctId}"
             Style="{StaticResource documentTextBoxStyle}"
             ToolTipService.ToolTip="Right Click to modify parameters" >
        <toolkit:ContextMenuService.ContextMenu >
            <toolkit:ContextMenu >
                <toolkit:MenuItem Header="Test" Click="MenuItem_Click"/>
            </toolkit:ContextMenu>
        </toolkit:ContextMenuService.ContextMenu>
    </TextBox>
</DataTemplate>

Answer 1

There's really no need for a workaround, it's as simple as using the databinding:

(sender as MenuItem).DataContext as TextBox

Will give you the TextBox you're after. (Storing stuff in the Tag field is really not something you want to clutter your code with.)