Then there are some problems (like this and this) where WPF leaks for you too.Finally, there are things (this, this, this, this, this, and this) that simply perform worse than you likely expect.The Horizontal Alignment and Vertical Alignment properties are used to set horizontal and vertical alignments.
The Affects Arrange flag will cause Invalidate Arrange() to be called on the target element when the property changes.
This leads us to another relative source mode which is the Find Ancestor one. Mode Find Ancestor In this case, a property of a given element will be tied to one of its parents, Of Corse.
The main difference with the above case is the fact that, it's up to you to determine the ancestor type and the ancestor rank in the hierarchy to tie the property.
This is done by combining the desired flags using a bitwise “OR” and then passing that value into the appropriate Dependency Property. As an example, the Width property on Framework Element is registered with the Affects Measure option.
As such, the property engine will take care of invalidating measure on the target element whenever the Width property changes.