ios - Swift 3 UIScrollview 不要求缩放

Question

这让我抓狂!

我的 UIScrollView 基于 http://koreyhinton.com/blog/uiscrollview-crud.html为了使其程序化，所以在我的 ScrollView 中设置了一个容器 View 。但它平移，但不会缩放。

BinaryTreeViewController 类:UIViewController、UIScrollViewDelegate {

var scrollView: UIScrollView!
var containerView : UIView!

override func viewDidLoad() {
    super.viewDidLoad()

    let width:CGFloat  = self.view.bounds.width
    let height:CGFloat = self.view.bounds.height

    scrollView = UIScrollView()
    scrollView.delegate = self
    scrollView.minimumZoomScale = 0.5
    scrollView.maximumZoomScale = 2.0
    scrollView.contentSize = CGSize(width: width*2, height: 2000)

    scrollView.backgroundColor = .red
    containerView = UIView()

    scrollView.addSubview(containerView)
    view.addSubview(scrollView)

    containerView.isUserInteractionEnabled = true
    scrollView.isUserInteractionEnabled = true
}

override func viewDidLayoutSubviews() {

    super.viewDidLayoutSubviews()

    scrollView.frame = view.bounds
    containerView.frame = CGRect(x: 0, y: 0, width: scrollView.contentSize.width, height: scrollView.contentSize.height)
}



override func viewWillLayoutSubviews() {
        //I create a view called "theView"
        containerView.addSubview(theView)
 }

以下函数在任何时候都不会触发

func update(zoomScale: CGFloat, offSet: CGPoint) {
    scrollView.zoomScale = zoomScale
}

func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
    return containerView
}

func scrollViewDidZoom(_ scrollView: UIScrollView) {
    NSLog("scroll")
}

Answer 1

您真的不需要为此编写那么多代码。您可以在 Storyboard 中设置 ScrollView 所需的所有内容，并且只需要为要缩放的 View 设置导出。设置 Controller ，添加 ScrollView ，将委托(delegate)属性连接到 View Controller ，在 IB 中添加缩放 View 作为 subview 。

在类中，使 Controller 符合 UIScrollViewDelegate，并使用 viewForZooming，一个 scrollView 委托(delegate)方法。

class ViewController: UIViewController, UIScrollViewDelegate {

@IBOutlet weak var zoomer: UIImageView!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a   nib.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func viewForZooming(in scrollView: UIScrollView) -> UIView? {
        return zoomer
    }
}

附言使用更新的资源进行学习，Ray Wenderlich、AppCoda 等 - 这是一个充满优质资源的大型网络，而且 Swift 一直在不断变化。