swift - 自定义下拉菜单动画乱七八糟？

Question

我正在尝试使用 swift 创建自定义下拉菜单。我已经创建了菜单，并且正在尝试将其动画化。动画发生了，但是动画的效果有些乱。

请参阅此链接:https://drive.google.com/file/d/13BqdYphuCcZAoEV0jG1lyF0k43Pd2JYs/view?usp=sharing

我正在尝试获得正常的平滑下拉和上拉效果。请问有人可以建议吗？

我的代码:

var editButton: UIButton = {
    let btn = UIButton()
    btn.setTitle("Edit", for: .normal)
    btn.backgroundColor = UIColor.appBlue.withAlphaComponent(0.5)
    btn.addTarget(self, action: #selector(editTable), for: .touchUpInside)
    btn.isHidden = true
    return btn
}()

var createFolderButton: UIButton = {
    let btn = UIButton()
    btn.setTitle("Create Folder", for: .normal)
    btn.backgroundColor = UIColor.appBlue.withAlphaComponent(0.5)
    btn.addTarget(self, action: #selector(createFolder), for: .touchUpInside)
    btn.isHidden = true
    return btn
}()

var signOutButton: UIButton = {
    let btn = UIButton()
    btn.setTitle("Sign Out", for: .normal)
    btn.backgroundColor = UIColor.appBlue.withAlphaComponent(0.5)
    btn.addTarget(self, action: #selector(signOut), for: .touchUpInside)
    btn.isHidden = true
    return btn
}()

var allButtons: [UIButton]!





override func viewDidLoad() {
    super.viewDidLoad()
    view.backgroundColor = .white
    createDropDownMenu()
    setUpNavigationButton()
    allButtons = [createFolderButton, editButton, signOutButton]
}

private func createDropDownMenu(){

    // StackView
    let stackView = UIStackView()
    stackView.axis = .vertical
    stackView.distribution = .fill
    stackView.alignment = .center

    stackView.addArrangedSubview(createFolderButton)
    stackView.addArrangedSubview(editButton)
    stackView.addArrangedSubview(signOutButton)

    editButton.translatesAutoresizingMaskIntoConstraints = false
    editButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
    editButton.widthAnchor.constraint(equalTo: stackView.widthAnchor).isActive = true

    createFolderButton.translatesAutoresizingMaskIntoConstraints = false
    createFolderButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
    createFolderButton.widthAnchor.constraint(equalTo: stackView.widthAnchor).isActive = true

    signOutButton.translatesAutoresizingMaskIntoConstraints = false
    signOutButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
    signOutButton.widthAnchor.constraint(equalTo: stackView.widthAnchor).isActive = true

    view.addSubview(stackView)

    stackView.translatesAutoresizingMaskIntoConstraints = false
    stackView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    stackView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true
    stackView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
}

private func setUpNavigationButton(){
    // NavigationBar Button
    let rightButton = UIBarButtonItem.menuButton(target: self, action: #selector(expandMenu), imageName: "expand", navigationBar: navigationController!.navigationBar)
    navigationController?.navigationBar.tintColor = .white
    navigationItem.rightBarButtonItem = rightButton
}

@objc func expandMenu() {
    print("expand menu")
    for btn in allButtons!{
        UIView.animate(withDuration: 2.0) {
            btn.isHidden = !btn.isHidden // Give value of isHidden the opposite of what is currently is
        }
    }
}

Answer 1

只需使用 this pod，它消除了大部分头痛