WinRT XAML Databinding: How to bind to a property to the parent's data context when binding within an ItemTemplate?

Question

I have a GridView for which I set the data context programmatically to the view model instance. The GridView's ItemsSource is bound to an observable collection (PagesToRead) which is a property on the view model.

Within the GridView.ItemTemplate, binding goes against the observable collection in the ItemsSource, but I want to bind the StackPanel's Background element to a different property on the view model.

I'm looking for the magic <Background="{Binding Path=BackgroundColor, Source=???}"> that will escape the current ItemsSource and bind to the BackgroundColor property on the view model.

Here's the elided XAML:

<Grid>
  <GridView x:Name="MainGrid" CanReorderItems="True" CanDragItems="True" 
    ItemsSource="{Binding Path=PagesToRead}"
    <GridView.ItemTemplate>
      <DataTemplate >
          <StackPanel>
            <Background="{Binding Path=BackgroundColor, Source=???}">
            <TextBlock Text="{Binding Path=Title}" 
          </StackPanel>
      </DataTemplate>
    </GridView.ItemTemplate>
  </GridView>
</Grid>

Tyler Tyler · Accepted Answer · 2015-04-07T05:18:23

I got an answer via another avenue (thanks Karl Erickson). What you do is:

<StackPanel Background="{Binding Path=DataContext.TileBackgroundColor,
                         ElementName=MainGrid">

WinRT XAML Databinding: How to bind to a property to the parent's data context when binding within an ItemTemplate?

1 Answers