startZoomChangedListener function
Listens for when the current document's zoom ratio is changed.
var zoomChangedCancel = startZoomChangedListener((zoom) {
print('flutter zoom changed. Current zoom is: $zoom');
});
Returns a function that can cancel the listener.
Implementation
CancelListener startZoomChangedListener(ZoomChangedListener listener) {
var subscription = _zoomChangedChannel
.receiveBroadcastStream(eventSinkId.zoomChangedId.index)
.listen(listener, cancelOnError: true);
return () {
subscription.cancel();
};
}