ios - 子类化 UITextField 以包含选择器和工具栏

Question

问题

我有一个具有用户注册 View 的应用程序。它有许多 UITextField，其中许多都有一个带有嵌入工具栏的选择器以关闭选择器，即:

myTextField.inputView = myPicker
myTextField.inputAccessoryView = myToolbar

基本上我想在我的应用程序的不同部分重用这些文本字段，所以我想到了 UITextField 的子类，比如 PickerUITextField。

尝试

我试过这样的:

class PickerUITextField: UITextField {
    let picker = UIPickerView()
    let toolbar = UIToolbar()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }

    private func setup() {
        withToolbar()
        self.inputView = self.picker
        self.inputAccessoryView = self.toolbar
    }

    private func withToolbar() {
        toolbar.barStyle = UIBarStyle.default
        toolbar.isTranslucent = true
        let space = UIBarButtonItem(barButtonSystemItem: .flexibleSpace,
                                    target: nil, action: nil)
        let doneButton = UIBarButtonItem(title: "Done", style: .done,
                                         target: self, action: #selector(removeToolBar))

        toolbar.setItems([space, doneButton], animated: false)
        toolbar.isUserInteractionEnabled = true
        toolbar.sizeToFit()
    }

    @objc func removeToolBar() {
        self.resignFirstResponder()
    }

}

问题

但是，我如何在 View Controller 中检测到用户按下了我的 PickerUITextField 的“完成”按钮？换句话说:

class UserRegistrationViewController: UIViewController {

    @IBOutlet weak var country: PickerUITextField!

    // I want this to be triggered whenever the country picker closes
    func didSelectCountry() {
      print("User selected \(country.text!)")
    }

}

谢谢你的帮助。

Answer 1

您可以在 PickerUITextField 中创建一个闭包来执行完成按钮操作。

class PickerUITextField: UITextField {
    let picker = UIPickerView()
    let toolbar = UIToolbar()
    var doneBtnAction:(() -> Void)?


    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }

    private func setup() {
        withToolbar()
        self.inputView = self.picker
        self.inputAccessoryView = self.toolbar
    }

    private func withToolbar() {
        toolbar.barStyle = UIBarStyle.default
        toolbar.isTranslucent = true
        let space = UIBarButtonItem(barButtonSystemItem: .flexibleSpace,
                                    target: nil, action: nil)
        let doneButton = UIBarButtonItem(title: "Done", style: .done,
                                         target: self, action: #selector(removeToolBar))

        toolbar.setItems([space, doneButton], animated: false)
        toolbar.isUserInteractionEnabled = true
        toolbar.sizeToFit()
    }

    @objc func removeToolBar() {
        doneBtnAction?()
        self.resignFirstResponder()
    }

}

并且在您的 View Controller 中，您可以分配一个闭包。当您点击完成按钮时，它将被调用。

class UserRegistrationViewController: UIViewController {

    @IBOutlet weak var country: PickerUITextField!

    override func viewDidLoad() {
        super.viewDidLoad()
        country.doneBtnAction = { [weak self] in
            print("User selected \(self?.country.text!)")
        }
    }
}