iOS一起使用CLLocation和MapView获取坐标并更新地图

Question

I have an application which needs to do two things;

1. Get the current location
2. Update the Mapview to that location

I am using the following code;

-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation     *)newLocation fromLocation:(CLLocation *)oldLocation
{
    CLLocation *currentLocation = newLocation;
    if (currentLocation != nil) {
    NSLog(@"%.8f", currentLocation.coordinate.longitude);
    NSLog(@"%.8f", currentLocation.coordinate.latitude);
    NSLog(@"%f", currentLocation.speed);

    MKCoordinateRegion mapRegion;
    mapRegion.center.longitude = currentLocation.coordinate.longitude;
    mapRegion.center.latitude = currentLocation.coordinate.latitude;
    mapRegion.span.latitudeDelta = 0.03;
    mapRegion.span.longitudeDelta = 0.03;
    [_mapView setRegion:mapRegion animated: YES];
}
}

Everything happens as I expect, except for one thing. When the MapView region updates, the MAP moves, but the PIN does not. Eventually, the user pin is off the screen because the map is moving in line with the coordinates.

Any help would be greatly appreciated.

Answer 1

Below where you set region of _mapView, you should also create a new annotation with currentLocation and add it to the _mapView. The code should look like,

-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation     *)newLocation fromLocation:(CLLocation *)oldLocation
{
    CLLocation *currentLocation = newLocation;
    if (currentLocation != nil) {
    NSLog(@"%.8f", currentLocation.coordinate.longitude);
    NSLog(@"%.8f", currentLocation.coordinate.latitude);
    NSLog(@"%f", currentLocation.speed);

    MKCoordinateRegion mapRegion;
    mapRegion.center.longitude = currentLocation.coordinate.longitude;
    mapRegion.center.latitude = currentLocation.coordinate.latitude;
    mapRegion.span.latitudeDelta = 0.03;
    mapRegion.span.longitudeDelta = 0.03;
    [_mapView setRegion:mapRegion animated: YES];

    MyAnnotation *ant = [[MyAnnotation alloc] initWithCoordinate:currentLocation.coordinate];
    [_mapView addAnnotation:ant];
}