Bind to ItemsControl's DataContext from inside an ItemTemplate

问题

I have an ItemsControl whose for the ItemTemplate DataTemplate contains a Button. I want the Command on the button to bind to a Command on the DataContext of the ItemsControl, not the ItemTemplate. I think the solution has to do with using RelativeSource, but my attempts so far have failed:

<ItemsControl ItemsSource=\"{Binding Games}\">        
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <Button Command=\"{Binding Path=GameSelectedCommand, Source={RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}}\" 
                    CommandParameter=\"{Binding}\" 
                    Style=\"{StaticResource MenuButtonStyle}\" 
                    Content=\"{Binding Name}\"/>    
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

How can I get the Button to bind to the GameSelectedCommand of the ItemsControl\'s DataContext object?

回答1:

You're setting the source of the binding to the ItemsControl itself. Therefore, you'll need to dereference the DataContext of the ItemsControl:

Command="{Binding DataContext.GameSelectedCommand, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ItemsControl}}}"

How would you have known this? Take a look at your debug output window when running the app. You'll see a message along the lines of "Cannot resolve property 'GameSelectedCommand' on type 'ItemsControl'".

来源：https://stackoverflow.com/questions/1511516/bind-to-itemscontrols-datacontext-from-inside-an-itemtemplate

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