set TintColor to MKAnnotationView image

Question

I'm writing an application for iOS 7.0+ and I wanted to use new feature witch is: imageWithRenderingMode. I have a map annotation with this code:

-(MKAnnotationView*)annotationView {
    MKAnnotationView *annotationView = [[MKAnnotationView alloc] initWithAnnotation:self reuseIdentifier:@"AnnotationIdentifier"];
    annotationView.enabled = YES;
    annotationView.canShowCallout = YES;
    annotationView.image = [[UIImage imageNamed:@"star"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
    annotationView.rightCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
    annotationView.tintColor = [UIColor redColor];
    return annotationView;
}

I was expected that my pins will be red, but stays black, only the callout (i) icon turns red.

I was trying to set self.view.tintColor and self.mapView.tintColor in my ViewController but this not working either. How to turns this pins red?

Answer 1

There's a better solution than those proposed that doesn't involve creating a UIImageView.

This Swift code will create a colored version of your UIImage.

extension UIImage {

    func colorized(color : UIColor) -> UIImage {
        let rect = CGRectMake(0, 0, self.size.width, self.size.height);
        UIGraphicsBeginImageContextWithOptions(rect.size, false, 0.0);
        let context = UIGraphicsGetCurrentContext();
        CGContextSetBlendMode(context, .Multiply)
        CGContextDrawImage(context, rect, self.CGImage)
        CGContextClipToMask(context, rect, self.CGImage)
        CGContextSetFillColorWithColor(context, color.CGColor)
        CGContextFillRect(context, rect)
        let colorizedImage = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        return colorizedImage
    }
}

Call it like this:

UIImage(named: "myImage")!
    .imageWithRenderingMode(.AlwaysTemplate)
    .colorized(UIColor.red())

Answer 2

I could make this work by capturing an UIView to UIImage:

UIImage *pin = [UIImage imageNamed:@"pin"];
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, pin.size.width, pin.size.height)];
imageView.image = [pin imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
imageView.tintColor = [UIColor grayColor]; // set the desired color

// now the magic...
UIGraphicsBeginImageContextWithOptions(imageView.bounds.size, imageView.opaque, 0.0);
[imageView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

annotationView.image = img;