图片处理的部分

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();