The alignment for overlay in relation to this view.
A view that layers overlay in front of this view.
When you apply an overlay to a view, the original view continues to provide the layout characteristics for the resulting view. For example, the layout for the caption in this view fits within the width of the image:
This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.