startZooming method
Implementation
void startZooming(ScaleUpdateDetails details) async {
if (!_initialized || value.pointers != 2) {
return;
}
value = value.copyWith(
currentScale: (value.baseScale * details.scale)
.clamp(value.minAvailableZoom, value.maxAvailableZoom),
);
await _controller.setZoomLevel(value.currentScale);
}