无法写入（添加 UIImage）到相册

Question

我有以下代码

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

NSLog(@"failed");
}

来检查错误，并打印出我运行以下代码的时间：

-(IBAction) addWallpaper{

UIImageWriteToSavedPhotosAlbum( [UIImage imageNamed:[NSString stringWithFormat:@"%d.png", r]]
                               , self, @selector(image:didFinishSavingWithError:contextInfo:), nil );
}

如何正确地将 UIImage 保存到相册？

Answer 1

尽管名称

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

并不表示错误。您需要检查传递给此函数的error。

像这样的东西：

-(void)image:(UIImage *)image didFinishSavingWithError:(NSError*)error
                                  contextInfo:(void*)contextInfo
{
    UIAlertView *alert;
    if ( [error code] != 0 )
    {
            alert = [[UIAlertView alloc] initWithTitle:@"Sorry"
                       message:@"Things went wrong!"
                       delegate:nil
                       cancelButtonTitle:nil
                       otherButtonTitles:@"OK",nil];
    } else {
            alert = [[UIAlertView alloc] initWithTitle:@"Great"
                       message:@"Image was saved!"
                       delegate:nil
                       cancelButtonTitle:nil
                       otherButtonTitles:@"OK",nil];
    }
    [alert show];
    [alert release];
}