拖动地图时，只有相隔一定时间才从服务端取数据

- (void)mapView:(MAMapView *)mapView regionDidChangeAnimated:(BOOL)animated

{

        SEL getMapSelector = @selector(getMapData);

        [NSObject cancelPreviousPerformRequestsWithTarget:self selector:getMapSelector object:nil];

        [self performSelector:getMapSelector withObject:nil afterDelay:0.5];

拖动地图时，只有相隔一定时间才从服务端取数据

原文：http://blog.csdn.net/gaoyp/article/details/39180855