Focus on Canvas overlapping the listbox in WP7

I have a situation here. I have a page containing a ListBox. The ListBox is populated with Items if it is able to fetch the data from a web service. Now when the user doesn't have network connectivity on his phone or the webservice doesn't respond back with Ok status, I want to show the user a pop-up with an option to Retry or select Ok to stay on the same page (though it sounds dumb). Now for this I used a Canvas:

<Canvas Name="Nonetwork" Height="150" Width="280" HorizontalAlignment="Center" VerticalAlignment="Center" Background="DodgerBlue" Visibility="Collapsed" Margin="111,160,92,160" >
    <TextBlock VerticalAlignment="Top" Height="120" Width="280" Text="No Network is currently availabe" TextAlignment="Center" TextWrapping="Wrap" Foreground="White" FontSize="28" />
    <Button Margin="30, 80" Height="60" Width="100" Content="OK" FontSize="18" Click="Ok_Click"/>
    <Button Margin="150, 80" Height="60" Width="100" Content="Retry" FontSize="18" Click="Retry_Click"/>                
</Canvas>

Well as most of you experienced guys would have guessed, the canvas is buried inside the开发者_StackOverflow listbox and is not accessible when there is no network connectivity. So I have a blank page with the canvas but the user is not able to click on Ok or Retry. Please help

Please do let me know if there is any other approach to solve this problem. I tried Popup but I cant Navigate to the main page from a pop-up since that is a user control page. Any help is higly appreciated

Well, I placed my Canvas below the ListBox and the problem was solved. I didn't know that positioning of the controls in the XAML would have so much effect ...

The order in which elements are rendered in Silverlight is determined firstly by where they appear in the visual object hierarchy and secondly by their ZIndex property.

The Canvas has a third attached property named ZIndex that you can use to override the default layering of elements. Although this Canvas.ZIndex attached property is defined by the Canvas class, it actually works with any type of panel.

You can also try Canvas.ZIndex property:

Canvas.ZIndex Attached Property

What you do is a wrong practice and not at all recommended.

ChildWindow is the class you should use to display such kind of dialog.

Using a Popup is also another approach you can use.

NOTE: I know the simplest approach would be to use MessageBox.Show(), but it would create a popup out of silverlight frame and does not allow theming/styling and other customizations.