Q:

Silverlight element binding not working

I have a window that I want to appear to the left of existing content and am using element binding to do so.  This works perfectly in WPF but in Silverlight the window simply goes to the far right of the Canvas control its in and I dont know why?
<Grid x:Name="rightPanelGrid" HorizontalAlignment="Right" VerticalAlignment="Top" Margin="10,10,10,0">

<!-- Other xaml -->

<local:mywindow IToolkit:CanvasControl.Right="{Binding ElementName=rightPanelGrid, Path=ActualWidth}"

A:

Silverlight does not support binding to ActualWidth like this :(

For purposes of ElementName binding, ActualWidth does not post updates when it changes (due to its asynchronous and run-time calculated nature). Do not attempt to use ActualWidth as a binding source for an ElementName binding. If you have a scenario that requires updates based on ActualWidth, use a SizeChanged handler.

