iphone - UIScrollView覆盖UIButton

Question

我已经创建了一个UIScrollView，现在尝试在 ScrollView 上放置一个UIButton。但是，当我构建并运行应用程序时， ScrollView 仍然可以正常工作，但我看不到 UIButton。

我在界面构建器中链接了UIButton IBOutlet。

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    scrollView = [[UIScrollView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
    scrollView.backgroundColor = [UIColor blackColor];
    scrollView.delegate = self;
    scrollView.bounces = NO;

    backgroundImage = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"auckland-300.jpg"]];

    image = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"249a-134206f1d00-1342071f5d9.ImgPlayerAUCKLAND.png"]];

    // Note here you should size the container view appropriately and layout backgroundImage and image accordingly.
    containerView = [[UIView alloc] initWithFrame:CGRectMake(0,0,601,601)];
    playButton = [[UIButton alloc] init]; //test button cannot see it.
    [containerView addSubview:backgroundImage];
    [containerView addSubview:image];

    scrollView.contentSize = containerView.frame.size;
    [scrollView addSubview:containerView];

    scrollView.minimumZoomScale = 0.5;
    scrollView.maximumZoomScale = 31.0;
    [scrollView setZoomScale:scrollView.minimumZoomScale];
    self.view = scrollView;    
}

如有任何帮助，我们将不胜感激

Answer 1

一切似乎都很好。但我认为您看不到按钮 playButton 的原因是您没有将其添加到 view 本身。

你不需要这样做吗？ [containerView addSubview:playButton];

为了帮助您，这是我进行调试的方法 -

UIView implements a useful description method. In addition, it implements a recursiveDescription method that you can call to get a summary of an entire view hierarchy.

NSLog(@"%@", [controller.view recursiveDescription]);