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

问题

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>

回答1:

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

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

来源：https://stackoverflow.com/questions/29483761/winrt-xaml-databinding-how-to-bind-to-a-property-to-the-parents-data-context-w