如何将多个UIImageViews合并为一个UIImage

Question

我有2个UIImageViews相互叠加(图片+覆盖框架),我想将它们保存到相机胶卷作为1张图片.

我应该如何组合这两个UIImageViews,以便我可以使用'结果'UIImage调用UIImageWriteToSavedPhotosAlbum函数？

Answer 1

+ (UIImage * ) mergeImage: (UIImage *) imageA
                                 withImage:  (UIImage *) imageB
                                 strength: (float) strength {

UIGraphicsBeginImageContextWithOptions(CGSizeMake(imageA.size.width, imageA.size.height), YES, 0.0); 

[imageA drawAtPoint: CGPointMake(0,0)];

[imageB drawAtPoint: CGPointMake(0,0) 
          blendMode: kCGBlendModeNormal // you can play with this
              alpha: strength]; // 0 - 1

UIImage *answer = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext();
return answer; }