HamburgerMenu doesn't handle DataContext inheritance for Menu items

I’m trying tu use HamburgerMenu with custom UserControls as items. Unfortunately, the Datacontext link is not propagated to the items usercontrol.

<Border Grid.Column="0"
                Margin="10 10 0 10"
                BorderBrush="{DynamicResource GrayBrush7}"
                BorderThickness="1">
		<Controls:HamburgerMenu x:Name="HamburgerMenuControl"
                                    HamburgerWidth="40"
                                    IsPaneOpen="True"
									ItemInvoked="HamburgerMenuControl_OnItemInvoked"
									ItemTemplate="{StaticResource MenuItemTemplate}"
                                    OptionsItemTemplate="{StaticResource MenuItemTemplate}"
                                    SelectedIndex="2"
                                    Style="{StaticResource HamburgerMenuCreatorsStyle}"
                                    VerticalScrollBarOnLeftSide="False">
			<!--  Items  -->
			<Controls:HamburgerMenu.ItemsSource>
				<Controls:HamburgerMenuItemCollection>
					<Controls:HamburgerMenuIconItem Icon="{iconPacks:Modern Kind=Clean}" Label="Clean">
						<Controls:HamburgerMenuIconItem.Tag>
								<views:Clean/>
							</Controls:HamburgerMenuIconItem.Tag>
					</Controls:HamburgerMenuIconItem>

I added in code behind the following event

private void HamburgerMenuControl_OnItemInvoked(object sender, HamburgerMenuItemInvokedEventArgs e)
		{
			HamburgerMenuControl.Content = e.InvokedItem;
			// Set the DataContext to the UserControl created dynamically when clicking on the menu
			((e.InvokedItem as HamburgerMenuIconItem).Tag as UserControl).DataContext = this.DataContext;
		}

This solve the problem, but not for the first time. Indeed when the application starts, the event is not invoked. Adding this kind of XAML code doesn’t work also.

DataContext="{Binding RelativeSource={RelativeSource AncestorType=UserControl}}"

Any idea ? Thank you

[punker76]

There are 3 options to solve this “known” problem:

System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=SomeProperty; DataItem=null; target element is ‘SomeElement’ (HashCode=123456789); target property is ‘AProperty’ (type ‘TypeOfTheProperty’)

This could be solved…

• by using a BindingProxy
• by using x:Reference

<Controls:HamburgerMenuIconItem x:Name="AboutOption"
                                Command="{Binding Source={x:Reference theHamburgerMenuElement}, Path=DataContext.ShowHamburgerAboutCommand}"
                                Label="About">
    <Controls:HamburgerMenuIconItem.Icon>
        <iconPacks:PackIconMaterial Width="22"
                                    Height="22"
                                    HorizontalAlignment="Center"
                                    VerticalAlignment="Center"
                                    Kind="Help" />
    </Controls:HamburgerMenuIconItem.Icon>
</Controls:HamburgerMenuIconItem>

• or simply adding the x:Name to the element SO

<Controls:HamburgerMenuIconItem x:Name="AboutOption"
                                Command="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=Controls:HamburgerMenu}, Path=DataContext.ShowHamburgerAboutCommand}"
                                Label="About">
    <Controls:HamburgerMenuIconItem.Icon>
        <iconPacks:PackIconMaterial Width="22"
                                    Height="22"
                                    HorizontalAlignment="Center"
                                    VerticalAlignment="Center"
                                    Kind="Help" />
    </Controls:HamburgerMenuIconItem.Icon>
</Controls:HamburgerMenuIconItem>

[SkinnySackboy]

I have just come across precisely the same issue, same symptoms as OP. The bizarre thing is that if I use Snoop and hit the control suddenly the DataContext gets set correctly. I’ve tried the binding proxy trick, it works but like the OP said not the first time, unless I use Snoop to “prod” it into action.