Asks your element if it wants to modify any layout attributes before they are applied.
- macOS 10.11+
The attributes provided by the layout object. These attributes represent the values that the layout object intends to apply to the element.
The final attributes to apply to the element.
The default implementation of this method returns the same attributes that are in the
layout parameter. You can override this method in subclasses and use it to return a different set of attributes. If you override this method, call
super first to give the system the opportunity to make changes, then modify the returned attributes.
In OS X 10.11, this method is never called.