为什么我的垂直编程滚动视图在 Swift 中不起作用

Question

我已经创建了一个测试项目，看看我是否可以让 swift 程序化滚动视图工作，但我就是无法让测试数据滚动。 这是我的测试代码。

import UIKit

class ViewController: UIViewController {

    private let viewLabel0: UILabel = {
        let label = UILabel()
        label.text = "Stephen 0"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    

    private let viewLabel1: UILabel = {
        let label = UILabel()
        label.text = "Stephen 1"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel2: UILabel = {
        let label = UILabel()
        label.text = "Stephen 2"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel3: UILabel = {
        let label = UILabel()
        label.text = "Stephen 3"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel4: UILabel = {
        let label = UILabel()
        label.text = "Stephen 4"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    
    private let viewLabel5: UILabel = {
        let label = UILabel()
        label.text = "Stephen 5"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel6: UILabel = {
        let label = UILabel()
        label.text = "Stephen 6"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    

    private let viewLabel7: UILabel = {
        let label = UILabel()
        label.text = "Stephen 7"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel8: UILabel = {
        let label = UILabel()
        label.text = "Stephen 8"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel9: UILabel = {
        let label = UILabel()
        label.text = "Stephen 9"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel10: UILabel = {
        let label = UILabel()
        label.text = "Stephen 10"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    
    private let viewLabel11: UILabel = {
        let label = UILabel()
        label.text = "Stephen 11"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel12: UILabel = {
        let label = UILabel()
        label.text = "Stephen 12"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()

    private let viewLabel13: UILabel = {
        let label = UILabel()
        label.text = "Stephen 13"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    
    private let viewLabel14: UILabel = {
        let label = UILabel()
        label.text = "Stephen 14"
        label.font = UIFont.systemFont(ofSize: 30)
        label.textColor = .white
        return label
    }()
    
    private lazy var scrollView: UIScrollView = {
        let sv = UIScrollView()
        sv.isScrollEnabled = true
        sv.contentSize = CGSize(width: self.view.frame.width, height: self.view.frame.height * 3.0)
        return sv
    }()
    
    private let contentView: UIView = {
        let cv = UIView()
        return cv
    }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        view.backgroundColor = UIColor.mainBackgroundColor
        
        view.addSubview(scrollView)
        scrollView.anchor(top: view.topAnchor,
                          left: view.leftAnchor,
                          bottom: view.bottomAnchor,
                          right: view.rightAnchor)
        
        scrollView.addSubview(contentView)
        contentView.anchor(top: scrollView.contentLayoutGuide.topAnchor,
                           left: scrollView.frameLayoutGuide.leftAnchor,
                           bottom: scrollView.contentLayoutGuide.bottomAnchor,
                           right: scrollView.frameLayoutGuide.rightAnchor,
                           paddingTop: 0,
                           paddingLeft: 0,
                           paddingBottom: 0,
                           paddingRight: 0)

        
        contentView.addSubview(viewLabel0)
        viewLabel0.anchor(top: view.safeAreaLayoutGuide.topAnchor, paddingTop: 40.0)
        viewLabel0.centerX(inView: contentView)

        contentView.addSubview(viewLabel1)
        viewLabel1.anchor(top: viewLabel0.bottomAnchor, paddingTop: 40.0)
        viewLabel1.centerX(inView: contentView)

        contentView.addSubview(viewLabel2)
        viewLabel2.anchor(top: viewLabel1.bottomAnchor, paddingTop: 40.0)
        viewLabel2.centerX(inView: contentView)

        contentView.addSubview(viewLabel3)
        viewLabel3.anchor(top: viewLabel2.bottomAnchor, paddingTop: 40.0)
        viewLabel3.centerX(inView: contentView)

        contentView.addSubview(viewLabel4)
        viewLabel4.anchor(top: viewLabel3.bottomAnchor, paddingTop: 40.0)
        viewLabel4.centerX(inView: contentView)

        contentView.addSubview(viewLabel5)
        viewLabel5.anchor(top: viewLabel4.bottomAnchor, paddingTop: 40.0)
        viewLabel5.centerX(inView: contentView)

        contentView.addSubview(viewLabel6)
        viewLabel6.anchor(top: viewLabel5.bottomAnchor, paddingTop: 40.0)
        viewLabel6.centerX(inView: contentView)

        contentView.addSubview(viewLabel7)
        viewLabel7.anchor(top: viewLabel6.bottomAnchor, paddingTop: 40.0)
        viewLabel7.centerX(inView: contentView)

        contentView.addSubview(viewLabel8)
        viewLabel8.anchor(top: viewLabel7.bottomAnchor, paddingTop: 40.0)
        viewLabel8.centerX(inView: contentView)

        contentView.addSubview(viewLabel9)
        viewLabel9.anchor(top: viewLabel8.bottomAnchor, paddingTop: 40.0)
        viewLabel9.centerX(inView: contentView)

        contentView.addSubview(viewLabel10)
        viewLabel10.anchor(top: viewLabel9.bottomAnchor, paddingTop: 40.0)
        viewLabel10.centerX(inView: contentView)

        contentView.addSubview(viewLabel11)
        viewLabel11.anchor(top: viewLabel10.bottomAnchor, paddingTop: 40.0)
        viewLabel11.centerX(inView: contentView)

        contentView.addSubview(viewLabel12)
        viewLabel12.anchor(top: viewLabel11.bottomAnchor, paddingTop: 40.0)
        viewLabel12.centerX(inView: contentView)

        contentView.addSubview(viewLabel13)
        viewLabel13.anchor(top: viewLabel12.bottomAnchor, paddingTop: 40.0)
        viewLabel13.centerX(inView: contentView)

        contentView.addSubview(viewLabel14)
        viewLabel14.anchor(top: viewLabel13.bottomAnchor, paddingTop: 40.0)
        viewLabel14.centerX(inView: contentView)

        
        
        
    }


}

我觉得我已经尝试了从查看堆栈溢出到在线搜索的所有方法，但我就是无法让它滚动我创建的标签列表。

Answer 1

首先你不能在 viewDidLoad 中设置你的视图属性，因为在这个方法中视图加载没有出现，尝试将相同的代码放在 viewDidAppear 中并检查你滚动视图的内容大小属性，它应该与你的滚动内容大小匹配并且应该大于您查看滚动的大小，并且还保持滚动为滚动视图启用 true。

第二件事最好从你 storyboard 那里拿走卷轴。

参考实现的链接，我在谷歌上搜索你也可以尝试其他链接。

https://medium.com/@pradeep_chauhan/how-to-configure-a-uiscrollview-with-auto-layout-in-interface-builder-218dcb4022d7

Answer 2

需要以下代码

       view.addSubview(scrollView)
        scrollView.anchor(top: self.view.topAnchor,
                          bottom: self.view.bottomAnchor,
                          paddingTop: 0,
                          paddingBottom: 0)
        scrollView.trail(left: self.view.leadingAnchor,
                         right: self.view.trailingAnchor,
                         leftT: 0,
                         rightT: 0)
        
        scrollView.addSubview(contentView)
        contentView.topAnchor.constraint(equalTo: scrollView.topAnchor).isActive = true;
        contentView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor).isActive = true;
        contentView.leadingAnchor.constraint(equalTo: scrollView.leadingAnchor).isActive = true;
        contentView.trailingAnchor.constraint(equalTo: scrollView.trailingAnchor).isActive = true;