This interface designates that its implementor needs to be informed whenever its size is modified.

Widgets that implement this interface should only be added to those that implement {@link ProvidesResize}. Failure to do so will usually result in {@link #onResize()} not being called.

abstract class RequiresResize {

 /**
  * This method must be called whenever the implementor's size has been
  * modified.
  */
 void onResize();
}