RenderSemanticsGestureHandler constructor Null safety

RenderSemanticsGestureHandler(
  1. {RenderBox? child,
  2. GestureTapCallback? onTap,
  3. GestureLongPressCallback? onLongPress,
  4. GestureDragUpdateCallback? onHorizontalDragUpdate,
  5. GestureDragUpdateCallback? onVerticalDragUpdate,
  6. double scrollFactor = 0.8,
  7. HitTestBehavior behavior = HitTestBehavior.deferToChild}
)

Creates a render object that listens for specific semantic gestures.

The scrollFactor and behavior arguments must not be null.

Implementation

RenderSemanticsGestureHandler({
  RenderBox? child,
  GestureTapCallback? onTap,
  GestureLongPressCallback? onLongPress,
  GestureDragUpdateCallback? onHorizontalDragUpdate,
  GestureDragUpdateCallback? onVerticalDragUpdate,
  this.scrollFactor = 0.8,
  HitTestBehavior behavior = HitTestBehavior.deferToChild,
}) : assert(scrollFactor != null),
     _onTap = onTap,
     _onLongPress = onLongPress,
     _onHorizontalDragUpdate = onHorizontalDragUpdate,
     _onVerticalDragUpdate = onVerticalDragUpdate,
     super(behavior: behavior, child: child);