MapView设置范围(Obj-C)

点击按钮返回定位点

- (IBAction)backButtonClick:(id)sender {
    
    // 方式一: 以动画方式设置用户跟踪模式返回
    /*
     MKUserTrackingModeNone = 0, // the user's location is not followed
     MKUserTrackingModeFollow, // the map follows the user's location
     MKUserTrackingModeFollowWithHeading __TVOS_PROHIBITED, // the map follows the user's location and heading
     */
    [self.mapView setUserTrackingMode:MKUserTrackingModeFollow animated:YES];
    
    
    // 方式二: 设置地图范围  到定位点
    // 中心点为定位点经纬度
    /**
     *
     typedef struct {
     CLLocationCoordinate2D center;  中心点  确定地图的位置
     MKCoordinateSpan span;  经纬度跨度       确定地图的大小
     } MKCoordinateRegion;
     */
    
    /**
     *
     typedef struct {
     CLLocationDegrees latitudeDelta;  纬度跨度 1°=111km
     CLLocationDegrees longitudeDelta; 经度跨度
     } MKCoordinateSpan;
     */
    
    // OC 中结构体不能直接赋值,所以先要取出来,设置后重新赋值回去
    CLLocationCoordinate2D center = CLLocationCoordinate2DMake(self.mapView.userLocation.location.coordinate.latitude, self.mapView.userLocation.location.coordinate.longitude);
    //跨度为地图当前的跨度
    //设置地图范围
    [self.mapView setRegion:MKCoordinateRegionMake(center, self.mapView.region.span) animated:YES];
    

    
}