handleEvent method
To customize the necessary pointer events in behaviors. (e.g., CrosshairBehavior, TrackballBehavior, ZoomingBehavior).
Implementation
@override
void handleEvent(PointerEvent event, BoxHitTestEntry entry) {
if (event is PointerScrollEvent || event is PointerPanZoomUpdateEvent) {
_performMouseWheelZooming(event);
}
}