作爲UIImage捕獲UIView

Question

我一直在使用這種方法將UIView轉換成UIImage。即視圖的屏幕快照 -

@interface UIView(Extended) 

- (UIImage *) imageByRenderingView; 

@end 


@implementation UIView(Extended) 


- (UIImage *)imageByRenderingView 
{ 
    UIGraphicsBeginImageContext(self.bounds.size); 
    [self.layer renderInContext:UIGraphicsGetCurrentContext()]; 
    UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext(); 
    UIGraphicsEndImageContext(); 
    return resultingImage; 
} 

@end 

要使用它，我這樣做 -

UIImage *currImage = [self.view imageByRenderingView];

這使整個UIView的圖像表示。現在我想要2張圖片，其中一張是UIView的上半部分，另一張是下半部分。我怎麼做？

Answer 1

您可以通過使用此代碼一分爲二的UIImage：

CGImageRef topOfImageCG = 
     CGImageCreateWithImageInRect(currImage.CGImage, 
             CGRectMake(0, 
               0, 
               currImage.size.width, 
               currImage.size.height/2.0)); 

UIImage *topOfImage = [UIImage imageWithCGImage:topOfImageCG]; 

CGImageRelease(topOfImageCG);