Animate non-fixed width

I've been working with WPF for some time. I'm searching for a way to animate a non-fixed width of elements with double animation, it seems that i can't give From="0" To="*" or From="0" To="Auto" for Storyboard.TargetProperty="Height".

I assume i have to work with precenteges, something like:

<DoubleAnimation ... ... ... From="0%" To="100%" 

I Know there is a way to do it with VisualStateManager, if th开发者_开发百科is is the only option - i would appreciate a reference of on how to do it.

Thanx alot Gili

Whenever I want to animate Height or Width without setting a fixed value, as when collapsing/expanding a panel, I manage to do it by animating MinWidth, MinHeight, MaxWidth, and MaxHeight properties instead.

You might be able to do the same, but without more specifics I can't go beyond that.