Detecting When the Map Stops in Google Maps SDK for iOS

An addition to this post. There I mentioned among the problems that Google Maps only provides the event mapView: didChangeCameraPosition:, which fires at every tiny movement of the map, even while the finger is still on the screen. If you move your finger slowly across the map and some markers are supposed to appear via external HTTP requests, it manages to send 10-15 requests per second. That is of course unacceptable, especially on mobile internet.

But you can handle this yourself, more specifically with UIPanGestureRecognizer.

Code cheat sheet:

// где-то в коде проекта
panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(mapDidChange:)];
[panRecognizer setMinimumNumberOfTouches:1];
[panRecognizer setMaximumNumberOfTouches:1];

// GoogleMapsView это гуглокарта, класс GMSMapView
GoogleMapsView.gestureRecognizers = @[panRecognizer];

//.. метод, реагирующий на отпускание касания
-(void)mapDidChange:(UIPanGestureRecognizer *)pan {
    if ( panRecognizer.state == UIGestureRecognizerStateBegan ) {
        // ничего не делать, но можно и что-нибудь делать
    }
    if ( panRecognizer.state == UIGestureRecognizerStateEnded ) {
        // палец отпущен, можно делать то, что нужно, например:
        [self sendMapRequest];
    }
}

That is it: you attach the gesture recognizer to the Google map. When the finger is released, you perform the required actions. Theoretically this can even replace mapView: didChangeCameraPosition: if needed.