1、截取部分UIImage
-(UIImage *)clipImageFromImage:(UIImage *)orgImage Rect:(CGRect)clipRect{ CGImageRef imageRef = orgImage.CGImage; CGImageRef subImageRef = CGImageCreateWithImageInRect(imageRef, clipRect); CGSize size; size = clipRect.size; UIGraphicsBeginImageContext(size); CGContextRef context = UIGraphicsGetCurrentContext(); CGContextDrawImage(context, clipRect, subImageRef); UIImage* clipImage = [UIImage imageWithCGImage:subImageRef]; CGImageRelease(subImageRef); UIGraphicsEndImageContext(); return clipImage; }
2图片合成:
- (UIImage *)addImage:(UIImage *)image1 toImage:(UIImage *)image2 { UIGraphicsBeginImageContext(image1.size); [image1 drawInRect:CGRectMake(0, 0, image1.size.width, image1.size.height)]; [image2 drawInRect:CGRectMake(0, 0, image2.size.width, image2.size.height)]; UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return resultingImage; }
3画纯色UIImage
CGSize imageSize = CGSizeMake(50, 50); UIGraphicsBeginImageContextWithOptions(imageSize, 0, [UIScreen mainScreen].scale); [[UIColor colorWithRed:0 green:0 blue:0 alpha:1.0] set]; UIRectFill(CGRectMake(0, 0, imageSize.width, imageSize.height)); UIImage *pressedColorImg = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext();