listbox scrollbar not visible when item height is too big

I have a stackpanel of height 100 and I have a Listbox inside the stackpanel. The Listbox has items which are开发者_运维知识库 bigger than 100 in height (150 for example).

The listbox's scrollbar in this case as the a single item itself is taller than the actual height of the stackpanel.

How do we get the scrollbar to comeup in this situation.

Thanks.

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The StackPanel does not constrain the child ListBox height. It is just clipping it.

Use a grid instead or constrain the ListBox to the same height as the StackPanel. Stretching child controls to a StackPanel (in the direction of StackPanel-growth) does not work.