如何控制百度地图的显示范围 ios软件开发

CLLocationCoordinate2D coor;

    coor.latitude = latiInt;

    coor.longitude = longiInt;

    pointAnnotation.coordinate = coor;

    

    BMKCoordinateSpan span = BMKCoordinateSpanMake(0.01, 0.01);

    BMKCoordinateRegion regin = BMKCoordinateRegionMake(coor, span);

    [self.mapView setRegion:regin];