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 PointerMoveEvent) {
_handlePointerMove(event);
} else if (event is PointerHoverEvent) {
_handlePointerHover(event);
} else if (event is PointerCancelEvent) {
_hideTrackball(immediately: true);
} else if (event is PointerUpEvent) {
_hideTrackball();
}
}