google map iOS get current map view bound

// work only on real device, not work on simulator

- (void)mapView:(GMSMapView *)mapView

idleAtCameraPosition:(GMSCameraPosition *)cameraPosition {

    

    

    

    // show current map view bound

    GMSVisibleRegion visibleRegion = [mapView_.projection visibleRegion];

    GMSCoordinateBounds *bounds = [[GMSCoordinateBounds alloc]initWithRegion:visibleRegion];

    

    CLLocationCoordinate2D northEast = bounds.northEast;

    CLLocationCoordinate2D northWest = CLLocationCoordinate2DMake(bounds.northEast.latitude, bounds.southWest.longitude);

    CLLocationCoordinate2D southEast = CLLocationCoordinate2DMake(bounds.southWest.latitude, bounds.northEast.longitude);

    

    CLLocationCoordinate2D  southWest = bounds.southWest;

    

    

    NSLog(@"NORTH-EST: %.5f",northEast.latitude);

    NSLog(@"NORTH-EST: %.5f",northEast.longitude);

    

    NSLog(@"NORTH-WEST: %.5f",northWest.latitude);

    NSLog(@"NORTH-WEST: %.5f",northWest.longitude);

    

    NSLog(@"South-EST: %.5f",southEast.longitude);

    NSLog(@"South-EST: %.5f",southEast.latitude);

    

    NSLog(@"SOUTH-WEST: %.5f",southWest.latitude);

    NSLog(@"SOUTH-WEST: %.5f",southWest.longitude);

    

}