iphone - UIView 内的 UIButton 不可点击

Question

我有点卡在这上面了，我在 UIViewController 中有一个 UIButton，但由于某些原因 UIButton 不是回应。

_downloadButton = [[DownloadButtonViewController alloc] init];
_downloadButton.issue = _issue;
_downloadButton.view.frame = CGRectMake(self.descriptionLabel.frame.origin.x, self.descriptionLabel.frame.origin.y + self.descriptionLabel.frame.size.height + 20, 200, 27);
[self.view addSubview:_downloadButton.view];

UIButton *tmpButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
tmpButton.titleLabel.text = @"test";
tmpButton.frame = CGRectMake(_downloadButton.view.frame.origin.x, _downloadButton.view.frame.origin.y - 30, _downloadButton.view.frame.size.width, _downloadButton.view.frame.size.height);
[self.view addSubview:tmpButton];

为了查看是否没有任何重叠，我添加了另一个 UIButton 稍微低一点，即使我将它添加到相同的位置它仍然有效。

我的应用程序结构是这样的

- UIViewController
    - UIScrollView
        - ThumbCover
            - UIImageView
            - DownloadButton --> NOT WORKING
            - UIButton --> WORKING
            - UILabel
        - ThumbCover
            - UIImageView
            - DownloadButton --> NOT WORKING
            - UIButton --> WORKING
            - UILabel
        - ThumbCover
            - UIImageView
            - DownloadButton --> NOT WORKING
            - UIButton --> WORKING
            - UILabel
        - ThumbCover
            - UIImageView
            - DownloadButton --> NOT WORKING
            - UIButton --> WORKING
            - UILabel

DownloadButton 只是一个简单的UIButton，没什么特别的。

Answer 1

您已将 viewcontroller 的 View 高度指定为 27

_downloadButton.view.frame = CGRectMake(self.descriptionLabel.frame.origin.x, self.descriptionLabel.frame.origin.y + self.descriptionLabel.frame.size.height + 20, 200, 27);

如果您的按钮的框架在其父 View ( View Controller 的 View )框架之外，即上述框架，它不会响应您的触摸