Can't set ZIndex in WPF

Question

I have xaml code like this:

Now what I want is: keep Height of The Black Grid , then set Height of The Red WrapPanel to 200 , but The Red WrapPanel is limited by The Black Grid . This will be like this: So how can I display full The Red WrapPanel ? (Condition: Always keep Height of The Black Grid , it's not allowed to resize or do anything) I was tried with Canvas.ZIndex but still doesn't work. Thank you all!

Answer 1

You can achieve this using negative margins. like so:

<WrapPanel Background="Red" Height="200" Margin="0 0 0 -100"/>

Hope this help you.