iOS, Draw text with stroke on UIImage - ios

Question

I am currently drawing text onto a UIImage which appears in an AnnotationView in an iOS Map - custom icons which appear at certain long/lat coordinates. Works well. However, I would like to draw this text with a white stroke (you might call it an outline).
// Draw text and add to a UIImage iOS 5/6
+ (UIImage*)drawText:(NSString*)string inImage:(UIImage*)image atPoint:(CGPoint)point {
UIFont *font = [UIFont boldSystemFontOfSize:12];
UIGraphicsBeginImageContext(image.size);
[image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];
CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[[UIColor whiteColor] set];
[string drawInRect:CGRectIntegral(rect) withFont:font];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}

Answer 1

NSAttributedString is definitely the way to go, especially if you want it to work in iOS7. For your example, you can just replace the two text blocks with the following:
// draw stroke
NSMutableDictionary *attributes = [[NSMutableDictionary alloc] init];
[attributes setObject:font forKey:NSFontAttributeName];
[attributes setObject:[NSNumber numberWithFloat:4] forKey:NSStrokeWidthAttributeName];
[attributes setObject:[UIColor whiteColor] forKey:NSStrokeColorAttributeName];
[self.text drawInRect:rect withAttributes:attributes];
// draw fill
[attributes removeObjectForKey:NSStrokeWidthAttributeName];
[attributes removeObjectForKey:NSStrokeColorAttributeName];
[attributes setObject:[UIColor blackColor] forKey:NSForegroundColorAttributeName];
[self.text drawInRect:rect withAttributes:attributes];

Answer 2

Took more time and effort than I thought, but in case anyone out there is looking for the same solution...Apparently not working under iOS7 and will update when I find the answer
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
UIImage *backgroundImage = [UIImage imageNamed:#"abstract_art_masterpiece_b.jpg"];
UIImage *textWithStrokeImage = [RJViewController drawTextWithStroke:#"unit 111"];
UIImage *image = [RJViewController placeImage:textWithStrokeImage onImage:backgroundImage];
self.imageView.image = image;
}
+ (UIImage*)placeImage:(UIImage*)image1 onImage:(UIImage*)image2 {
CGSize size = image2.size;
if ([UIScreen instancesRespondToSelector:#selector(scale)] && [[UIScreen mainScreen] scale] == 2.0f) {
UIGraphicsBeginImageContextWithOptions(size, NO, 2.0f);
} else {
UIGraphicsBeginImageContext(size);
}
[image2 drawAtPoint:CGPointMake(0, 0)];
[image1 drawAtPoint:CGPointMake(0, 0)];
UIImage* result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return result;
}
+ (UIImage*)drawTextWithStroke:(NSString*)string {
// set rect, size, font
CGRect rect = CGRectMake(0, 0, 88, 24);
CGSize size = CGSizeMake(rect.size.width, rect.size.height);
UIFont *font = [UIFont fontWithName:#"Helvetica-Bold" size:12];
// retina display, double resolution
if ([UIScreen instancesRespondToSelector:#selector(scale)] && [[UIScreen mainScreen] scale] == 2.0f) {
UIGraphicsBeginImageContextWithOptions(size, NO, 2.0f);
} else {
UIGraphicsBeginImageContext(size);
}
CGContextRef context = UIGraphicsGetCurrentContext();
// draw stroke
CGContextSetStrokeColorWithColor(context, [UIColor whiteColor].CGColor);
CGContextSetLineWidth(context, 4.0);
CGContextSetTextDrawingMode(context, kCGTextStroke);
[string drawInRect:CGRectIntegral(rect) withFont:font];
// draw fill
CGContextSetFillColorWithColor(context, [UIColor blackColor].CGColor);
CGContextSetTextDrawingMode(context, kCGTextFill);
[string drawInRect:CGRectIntegral(rect) withFont:font];
// convert to image and return
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}