swift - Xcode/Swift |随时了解 UISwitch 是否打开

Question

基本上，我们现在得到的是一个按钮，它根据文本字段是否填写来更改其颜色(灰色和绿色)...现在我想添加一个也必须打开的开关让按钮颜色变为绿色，如果没有，则变回灰色。我具体如何实现这部分？PS:setupAddTargetIsNotEmptyTextFields()在viewDidLoad()中调用

func setupAddTargetIsNotEmptyTextFields() {
    self.textField_username.addTarget(self, action: #selector(textFieldsIsNotEmpty), for: .editingChanged)
    self.textField_eMail.addTarget(self, action: #selector(textFieldsIsNotEmpty),
        for: .editingChanged)
    self.textField_password.addTarget(self, action: #selector(textFieldsIsNotEmpty), for: .editingChanged)
    self.textField_confirmPassword.addTarget(self, action: #selector(textFieldsIsNotEmpty),
        for: .editingChanged)
}

@objc func textFieldsIsNotEmpty(sender: UITextField) {

    sender.text = sender.text?.trimmingCharacters(in: .whitespaces)

    guard
        let username = self.textField_username.text, !username.isEmpty,
        let eMail = self.textField_eMail.text, !eMail.isEmpty,
        let password = self.textField_password.text, !password.isEmpty,
        let confirmPassword = self.textField_confirmPassword.text,
        password == confirmPassword
        else
    {
        //button is gray
        self.button_register.backgroundColor = UIColor(red:0.20, green:0.29, blue:0.37, alpha:1.0)
        return
    }
    //button is green
    self.button_register.backgroundColor = UIColor(red:0.10, green:0.74, blue:0.61, alpha:1.0)
}

Answer 1

When I just add the switch to the list, I first type in everything in the textFields and then enable the switch. At this moment the button is still gray. Then I have to first change something again in the textfields to make it work.

听起来发生的情况是开关未设置为像文本字段那样触发 textFieldsIsNotEmpty 操作。您可以很容易地解决这个问题:只需配置开关来调用该操作即可:

func setupAddTargetIsNotEmptyTextFields() {
    self.textField_username.addTarget(self, action: #selector(textFieldsIsNotEmpty), for: .editingChanged)
    // ...yada yada yada...        
    self.switch_selfDestructEnable.addTarget(self, action: #selector(textFieldsIsNotEmpty), for: .valueChanged)
}

现在，当值发生变化时，开关将发送 textFieldsIsNotEmpty，就像文本字段一样。接下来，修改 textFieldsIsNotEmpty() 以检查开关的状态以及各个文本字段的状态，您应该会得到您想要的行为。