Wpf control size to content?

Question

How do I make a WPF control to change its size according the content in it?

Answer 1

I had a user control which sat on page in a free form way, not constrained by another container, and the contents within the user control would not auto size but expand to the full size of what the user control was handed.

To get the user control to simply size to its content, for height only, I placed it into a grid with on row set to auto size such as this: