如何在不使用 UIPickerView 的情况下在 tvOS 中实现下拉列表？

Question

我正在尝试在我的 TVOS 应用中实现下拉菜单。显然，正确的做法是使用 UITextFieldView 和 UIPickerView。
结帐答案here.
问题是 UIPickerView 是not available in TVOS。
这种方法有没有可靠的替代方法？

Answer 1

我通过关注tutorial 找到了另一种方式。但是，它不是一个完美的解决方案，因为它在 TVOS 中的行为不同。 这是您应该使用的代码：

import UIKit

class CellClass: UITableViewCell {
    
}

class TestDropDownViewController: UIViewController {

    @IBOutlet weak var btnSelectFruit: UIButton!
    @IBOutlet weak var btnSelectGender: UIButton!
    
    let transparentView = UIView()
    let tableView = UITableView()
    
    var selectedButton = UIButton()
    
    var dataSource = [String]()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        tableView.delegate = self
        tableView.dataSource = self
        tableView.register(CellClass.self, forCellReuseIdentifier: "Cell")
    }
    
    func addTransparentView(frames: CGRect) {
        let window = UIApplication.shared.keyWindow
        transparentView.frame = window?.frame ?? self.view.frame
        self.view.addSubview(transparentView)
        
        tableView.frame = CGRect(x: frames.origin.x, y: frames.origin.y + frames.height, width: frames.width, height: 0)
        self.view.addSubview(tableView)
        tableView.layer.cornerRadius = 5
        
        transparentView.backgroundColor = UIColor.black.withAlphaComponent(0.9)
        tableView.reloadData()
        let tapgesture = UITapGestureRecognizer(target: self, action: #selector(removeTransparentView))
        transparentView.addGestureRecognizer(tapgesture)
        transparentView.alpha = 0
        UIView.animate(withDuration: 0.4, delay: 0.0, usingSpringWithDamping: 1.0, initialSpringVelocity: 1.0, options: .curveEaseInOut, animations: {
            self.transparentView.alpha = 0.5
            self.tableView.frame = CGRect(x: frames.origin.x, y: frames.origin.y + frames.height + 5, width: frames.width, height: CGFloat(self.dataSource.count * 50))
        }, completion: nil)
    }
    
    @objc func removeTransparentView() {
        let frames = selectedButton.frame
        UIView.animate(withDuration: 0.4, delay: 0.0, usingSpringWithDamping: 1.0, initialSpringVelocity: 1.0, options: .curveEaseInOut, animations: {
            self.transparentView.alpha = 0
            self.tableView.frame = CGRect(x: frames.origin.x, y: frames.origin.y + frames.height, width: frames.width, height: 0)
        }, completion: nil)
    }

    @IBAction func onClickSelectFruit(_ sender: Any) {
        dataSource = ["Apple", "Mango", "Orange"]
        selectedButton = btnSelectFruit
        addTransparentView(frames: btnSelectFruit.frame)
    }
    
    @IBAction func onClickSelectGender(_ sender: Any) {
        dataSource = ["Male", "Female"]
        selectedButton = btnSelectGender
        addTransparentView(frames: btnSelectGender.frame)
    }
}

extension TestDropDownViewController: UITableViewDelegate, UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return dataSource.count
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
        cell.textLabel?.text = dataSource[indexPath.row]
        return cell
    }
    
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        return 50
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        selectedButton.setTitle(dataSource[indexPath.row], for: .normal)
        removeTransparentView()
    }
}