Tinting UIImages

UIImage+Size.h

//
//  UIImage+Size.h
//  Quickie
//
//  Created by Kevin O'Neill on 13/03/11.
//  Copyright 2011 Kevin O'Neill. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIImage (Size)

- (CGFloat)width;
- (CGFloat)height;
- (CGRect)bounds;

@end

UIImage+Size.m

//
//  UIImage+Size.m
//  Quickie
//
//  Created by Kevin O'Neill on 13/03/11.
//  Copyright 2011 Kevin O'Neill. All rights reserved.
//

#import "UIImage+Size.h"

@implementation UIImage (Size)

- (CGFloat)width;
{
  return [self size].width;
}

- (CGFloat)height;
{
  return [self size].height;
}

- (CGRect)bounds;
{
  CGSize size = [self size];
  
  return CGRectMake(0., 0., size.width, size.height);
}

@end

UIImage+Tint.h

//  Quickie
//
//  Created by Kevin O'Neill on 15/03/11.
//  Copyright 2011 Kevin O'Neill. All rights reserved.
//

#import <UIKit/UIImage.h>

@interface UIImage (Tint)

+ (UIImage *)imageNamed:(NSString *)name tint:(UIColor *)tint;

- (UIImage *)tint:(UIColor *)tint;

@end

UIImage+Tint.m

//
//  Tint.m
//  Quickie
//
//  Created by Kevin O'Neill on 15/03/11.
//  Copyright 2011 Kevin O'Neill. All rights reserved.
//

#import "UIImage+Tint.h"

#import "UIImage+Size.h"

@interface TintedImageCache : NSObject
{
  @private
    NSMutableDictionary *cache_;
}

- (UIImage *)imageNamed:(NSString *)name tint:(UIColor *)tint;
- (void)addImageNamed:(NSString *)name tint:(UIColor *)tint image:(UIImage *)image;

@end

@implementation UIImage (Tint)

+ (TintedImageCache *)tintCache;
{
  static dispatch_once_t cache_initialized;
  static TintedImageCache *cache;
  
  dispatch_once(&cache_initialized, ^{
    cache = [[TintedImageCache alloc] init];
  });
  
  return cache;
}

+ (UIImage *)imageNamed:(NSString *)name tint:(UIColor *)tint;
{
  UIImage *result = [[self tintCache] imageNamed:name tint:tint];
  
  if (nil == result)
  {
    result = [[self imageNamed:name] tint:tint];
    if (nil != result)
    {
      [[self tintCache] addImageNamed:name tint:tint image:result];
    }
  }
  
  return result;
}

- (UIImage *)tint:(UIColor *)tint;
{
  NSAssert(tint != nil, @"tint must not be nil");
  
  UIGraphicsBeginImageContextWithOptions([self size], NO, 0.0);
  CGContextRef context = UIGraphicsGetCurrentContext();

  CGContextTranslateCTM(context, 0, [self height]);
  CGContextScaleCTM(context, 1.0, -1.0);
  
  [tint setFill];

  CGRect bounds = [self bounds];
  
  CGContextSetBlendMode(context, kCGBlendModeCopy);
  CGContextDrawImage(context, bounds, [self CGImage]);
  
  CGContextSetBlendMode(context, kCGBlendModeSourceIn);
  CGContextFillRect(context, bounds);
  
  UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  
  return image;
}

@end

inline static NSString *cachekey(NSString *name, UIColor *tint)
{
  return [name stringByAppendingPathComponent:[tint description]];
}

@implementation TintedImageCache

  // TODO: KAO - Add listener to memory warnings.

- (id)init
{
  if ((self = [super init]))
  {
    cache_ = [NSMutableDictionary dictionaryWithCapacity:13];
  }
  
  return self;
}

- (void)dealloc
{
  [cache_ release];
  
  [super dealloc];
}

- (UIImage *)imageNamed:(NSString *)name tint:(UIColor *)tint;
{
  return [cache_ objectForKey:cachekey(name, tint)];
}

- (void)addImageNamed:(NSString *)name tint:(UIColor *)tint image:(UIImage *)image;
{
  [cache_ setObject:image forKey:cachekey(name, tint)];
}

@end

Yeah , whoops

…

On 24/03/2011, at 1:42 PM, ittybittydude ***@***.*** wrote: Hey Kev, you might want to try retaining cache_ ;-) ## Reply to this email directly or view it on GitHub: https://gist.github.com/878969