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iosobjective-cmapkitscale

Display the map scale in mapkit

I am working with mapkit in Xcode 5.1 and am trying to display the map scale in regionDidChangeAnimated. I have no idea now to accomplish this though. I tried to look around and was unsuccessful. Any ideas?

EDIT:

-(void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated {

CGPoint nePoint = CGPointMake(self.mapView.bounds.origin.x + mapView.bounds.size.width, mapView.bounds.origin.y);
CGPoint swPoint = CGPointMake((self.mapView.bounds.origin.x), (mapView.bounds.origin.y + mapView.bounds.size.height));

CLLocationCoordinate2D neCoord;
neCoord = [self.mapView convertPoint:nePoint toCoordinateFromView:self.mapView];
CLLocationCoordinate2D swCoord;
swCoord = [self.mapView convertPoint:swPoint toCoordinateFromView:self.mapView];

CLLocationDistance distance = [neCoord distanceFromLocation:swCoord];
}

Any reason why I am getting an error with the last line, CLLocationDistance?

Solution

  • Use the methods that translate between the coordinates on the map and the points on the map view, such as convertPoint:toCoordinateFromView:. Use the edge points of your view for this.

    Now you have the coordinates - you can calculate the distances between the points with CLLocation's distanceFromLocation:. You can make some assumptions about the width of your view based on the physical properties of, day an iPhone or iPad and calculate the scale.