ScrollView contentSize 大于边界,但没有滚动

ScrollView contentSize Larger than Bounds, Yet No Scrolling

我有一个包含单个图像的滚动视图。图像的边界大于滚动视图的框架。我已将 scrollView 的 contentSize 设置为等于图像的边界。 但是没有滚动。我不知道是什么原因造成的。

 override func viewDidLoad() {
        super.viewDidLoad()
        var matches = SortThread.getSortThread().retrieveMatches()

        scrollView.frame = CGRectMake(0, navigationController!.navigationBar.frame.height - 20, UIScreen.mainScreen().bounds.width, view.bounds.height - (navigationController!.navigationBar.frame.height - 20))

        var imageName = String()
        imageName = matches[0].pictures![0]
        var parsedImageName = imageName.componentsSeparatedByString(".") as [String]
        var newImageName: String = parsedImageName[0] as String
        let path = NSBundle.mainBundle().pathForResource("MVLMP Images (Resized)/" + newImageName, ofType: "jpg")
        var image = UIImage()
        image = UIImage(contentsOfFile: path!)!
        var imageView = UIImageView(image: image)

        var ratio: CGFloat = image.size.width/image.size.height
        var screenHeight: CGFloat = UIScreen.mainScreen().bounds.height - navigationController!.navigationBar.frame.height - 20

        if(ratio > 1){

            imageView.frame = CGRectMake(0, 0, ((scrollView.bounds.width)/7) * 6, 0)
            imageView.frame = CGRectMake(0, 0, imageView.frame.width, imageView.frame.width * ratio)

        } else {

            imageView.frame =  CGRectMake(0, 0, 0, (screenHeight/9)*8)

            imageView.frame = CGRectMake(0, 0, imageView.frame.height * ratio, imageView.frame.height)

        }

        scrollView.addSubview(imageView)
        scrollView.contentSize.width = imageView.frame.width
        scrollView.contentSize.height = imageView.frame.height

    }

}

我已经打印出 scrollView.contentSize.width 和 scrollView.bounds.width,内容宽度实际上比边界宽度大大约 40。

正如 Muc Dong 评论的那样,我将图像的宽度添加到 scrollView 的 contentSize.width。这不一定是正确的做法,因为在我的情况下,图像之间存在一些我没有考虑的空白。这个边距应该包含在对 scrollView.contentSize.width 的添加中。