handlePointerUp method
Implementation
@override
void handlePointerUp(PointerUpEvent details) {
  if (explode &&
      explodeGesture == ActivationMode.singleTap &&
      _pointerHoldingTime != null &&
      DateTime.now().difference(_pointerHoldingTime!).inMilliseconds <
          kLongPressTimeout.inMilliseconds) {
    _handleExploding(details.localPosition);
  }
  super.handlePointerUp(details);
}