下载单张图片到本地相册

/**
*  保存到相册
*/
- (IBAction)save
{
if (self.imageView.image == nil) {
[SVProgressHUD showErrorWithStatus:@"图片并没下载完毕!"];
return;
}

// 将图片写入相册
UIImageWriteToSavedPhotosAlbum(self.imageView.image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
}
- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo
{
if (error) {
[SVProgressHUD showErrorWithStatus:@"保存失败!"];
} else {
[SVProgressHUD showSuccessWithStatus:@"保存成功!"];
}
}