截图保存到相册

   // 1.截图

    UIImage *image = [UIImage captureWithView:self.paintView];

    

    // 2.保存到图片

    UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

/**

 保存图片操作之后就会调用

 */

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo

{

    if (error) { // 保存失败

        [MBProgressHUD showError:@"保存失败"];

    } else { // 保存成功

        [MBProgressHUD showSuccess:@"保存成功"];

    }

}

+ (instancetype)captureWithView:(UIView *)view
{
    // 1.开启上下文
    UIGraphicsBeginImageContextWithOptions(view.frame.size, NO, 0.0);
    
    // 2.将控制器view的layer渲染到上下文
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];
    
    // 3.取出图片
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // 4.结束上下文
    UIGraphicsEndImageContext();
    
    return newImage;
}