Add text to GMSMapView - write on Google Map for iOS

Question

I want to add some text labels to GMSMapView. Of course the text should resize as the map zooms in and out. I don't see a text object in the Google Map SDK. How do I do this?

Answer 1

Here is the solution I came up with from @Saxon's suggestion, it's copied and pasted from my project so you'll have to modify to fit your needs. The idea is to render a UILabel into a UIImage, and then set the GMSGroundOverlay icon with that image. Then it resizes and all. GMSCoordinateBounds is constructed with a NorthEast and SouthWest point, so if you want to center the label at a point CenterX and CenterY you need to calculate it as below.

  UILabel *label = [UILabel new];      
  label.opaque = NO;
  label.text = @"H";
  label.font = [UIFont fontWithName: @"Arial-BoldMT" size: Normalize(32)];
  label.textColor = [UIColor blueColor];
  label.frame = CGRectMake(0, 0, Normalize(140), Normalize(140));
  label.textAlignment = NSTextAlignmentCenter;

  CLLocationDegrees offset = Normalize(0.03);  // change size here
  CLLocationDegrees southWestY = centerY - offset;
  CLLocationDegrees southWestX = centerX - offset;
  CLLocationDegrees northEastY = centerY + offset;
  CLLocationDegrees northEastX = centerX + offset;

  CLLocationCoordinate2D southWest = CLLocationCoordinate2DMake(southWestY,southWestX);
  CLLocationCoordinate2D northEast = CLLocationCoordinate2DMake(northEastY,northEastX);
  GMSCoordinateBounds *overlayBounds = [[GMSCoordinateBounds alloc] initWithCoordinate:southWest coordinate:northEast];

  GMSGroundOverlay *overlay = [GMSGroundOverlay groundOverlayWithBounds:overlayBounds icon:[self imageWithView:label]];
  overlay.bearing = 0;
  overlay.map = self.mapView

- (UIImage *) imageWithView:(UIView *)view
{
  UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.opaque, 0.0);
  [view.layer renderInContext:UIGraphicsGetCurrentContext()];
  UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  return img;
}