'Current location' BUTTON replica of the maps in iPhone

- (void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views {
for(MKAnnotationView *annotationView in views) {
    if(annotationView.annotation == mv.userLocation) {
        MKCoordinateRegion region;
        MKCoordinateSpan span;

        span.latitudeDelta=0.002;
        span.longitudeDelta=0.002; 

        CLLocationCoordinate2D location=mv.userLocation.coordinate;

        region.span=span;
        region.center=loc开发者_如何学Goation;

        [mv setRegion:region animated:TRUE];
        [mv regionThatFits:region];
    }
}

Hello all. I have tried searching other posts and websites. In essence I want to duplicate the 'Current location' BUTTON.

Using the above code, I was able to zoom into the users current location. This however is not flawless, sometimes the GPS updates a little late or thinks I am somewhere else, zooms to that location but then the blue dot will shift somewhere off screen to where I really am.

I was wondering is there a way I can add a 'Button', exactly like maps on the iphone. It doesn't need to gain a new zoom etc, simply move to the new updated locaiton. My main source of code would be almost replica to here.

I appreciate any help.

Create a custom annotation with the same graphic. This object must implement MKAnnotationView, and you have to return the custom view for it in the method mapView:viewForAnnotation: of the MKMapViewDelegate. If you want the exact graphic, use the project UIKit-Artwork-Extractor to get it.

Save a reference to the annotation view, subscribe to core location updates, and update the position calling something like:

- (void) animateView:(UIView *)view toPosition:(NSValue*)value
{
CGPoint newCenter = [value CGPointValue];
[UIView animateWithDuration:0.5
    animations:^{
        view.center = newCenter;
    }
    completion:^(BOOL finished){ }];
}

Then set the center of the map on the annotation:

- (void)centerMap:(CLLocation *)location {
    MKCoordinateRegion region = { { 0.0f, 0.0f }, { 0.0f, 0.0f } };
    region.center = location.coordinate;
    region.span.longitudeDelta = 0.15f; 
    region.span.latitudeDelta = 0.15f;
    [self.mapView setRegion:region animated:YES];
}