onLongPress property Null safety

GestureLongPressCallback? onLongPress

Called when the user presses on the render object for a long period of time.

Implementation

GestureLongPressCallback? get onLongPress => _onLongPress;
void onLongPress=(GestureLongPressCallback? value)

Implementation

set onLongPress(GestureLongPressCallback? value) {
  if (_onLongPress == value)
    return;
  final bool hadHandler = _onLongPress != null;
  _onLongPress = value;
  if ((value != null) != hadHandler)
    markNeedsSemanticsUpdate();
}