ios - 无法在 UIScrollView 中完全滚动

Question

我在 UIScrollView 中有一个 UIImageView，并且我希望能够滚动“常规”照片尺寸的尺寸。我的问题是我能够滚动，但是当它到达照片的顶部或底部时，滚动位置不会停留，而是“弹跳”并向上移动一点，并且不允许照片保持在那个位置，我该如何解决这个问题？

下面是代码:

 scrollView.frame = CGRect(x: self.view.frame.width * 0, y: self.view.frame.height / 3, width: self.view.frame.width, height: self.view.frame.width)
        self.view.addSubview(scrollView)
        scrollView.delegate = self


        let image = imageView.image
        imageView.frame = CGRect(x: self.view.frame.width * 0, y: self.view.frame.height * 0, width: (image?.size.width)!, height: (image?.size.height)!)
        imageView.frame = scrollView.bounds
        imageView.contentMode = .scaleAspectFill
        scrollView.addSubview(imageView)

举个例子，如果您用相机拍摄了一张全屏照片，然后当照片显示在 View 中时，整张照片在滚动时无法保持在其位置。

Answer 1

您做错了很多事情，并且如前所述，您应该转向自动布局和约束，但是...

要让您的图像按照您的方式滚动:

    // set scroll view frame to be full width of view, start 1/3 of the way down from the top, and make the height the same as the width
    scrollView.frame = CGRect(x: 0, y: self.view.frame.height / 3, width: self.view.frame.width, height: self.view.frame.width)

    // add the scroll view to the view
    self.view.addSubview(scrollView)

    // use "if let" so you're not force-unwrapping optionals
    if let image = imageView.image {

        // set the imageView's frame to the size of the image
        imageView.frame = CGRect(x: 0, y: 0, width: image.size.width, height: image.size.height)

        // add the imageView to the scroll view
        scrollView.addSubview(imageView)

        // set the contentSize of the scroll view - the "scrollable area" - to the size of the image view
        scrollView.contentSize = imageView.bounds.size
    }