onMouseRollOver property Null safety

EventStream<MouseEvent> onMouseRollOver

Dispatched when the user moves a pointing device over an InteractiveObject instance.

The event target is the object under the pointing device or a parent of that object. The rollOver events are dispatched consecutively down the parent chain of the object.

The purpose of the rollOver event is to simplify the coding of rollout behaviors for display object containers with children. When the mouse enters the area of a display object or the area of any of its children from an object that is not one of its children, the display object dispatches the rollOver event. This is different behavior than that of the onMouseOver event, which is dispatched each time the mouse enters the area of any child object of the display object container, even if the mouse was already over another child object of the display object container.

Implementation

EventStream<MouseEvent> get onMouseRollOver =>
    InteractiveObject.mouseRollOverEvent.forTarget(this);