How do I make an ItemsControl stretch to fill all availible space?

Question

I have an ItemsControl, with its ItemsSource bound to a list of items. The size of each of the items is as small as they can be, what I need is for the control and the items

Answer 1

I had the same problem and found out that ItemsControl by default uses a StackPanel for his children. Replacing this with a Grid solved the problem:

Edit: This only works for one child element!