Question

我创建了一个带有文本字段的UIAlertController，以及一个将验证码发送到用户电话号码的操作。但是，该操作也会解除警报控制器，使用户无法输入验证码。有没有办法让警报动作不解除警报控制器？

   let alertController = UIAlertController(title: "Verification", message: "a code has been sent to your phone number", preferredStyle: .alert)

let confirm = UIAlertAction(title: "Confirm", style: .default, handler: {
    alert -> Void in
    //verifies code
})

let resend = UIAlertAction(title: "Resend", style: .default, handler: {
        alert -> Void in
        //resends code
    })

let cancelAction = UIAlertAction(title: "Cancel", style: .default, handler: {
    (action : UIAlertAction!) -> Void in

})

alertController.addTextField { (textField : UITextField!) -> Void in
    textField.placeholder = "Enter code"
}

alertController.addAction(confirm)
alertController.addAction(resend)
alertController.addAction(cancelAction)

self.present(alertController, animated: true, completion: nil)

Answer 1

您可以使用UITextFieldDelegate的isEnabled和UIAlertAction属性来达到预期效果。

<强>步骤：

您的班级应该向UITextFieldDelegate
您的提醒操作应声明为类级属性
在显示警报
配置文本字段并将委托设置为您的类
实施shouldChangeCharactersIn:方法
如果文本长度大于所需长度，则启用警报操作，否则禁用警报操作

<强>代码：

// Your Class should confirm to UITextFieldDelegate
class ViewController: UIViewController, UITextFieldDelegate
{
    // Verify alert action, alert button that want to be disabled
    var verifyAction : UIAlertAction!

    // Shows the alert
    @IBAction func showAlert(sender : UIButton)
    {
        let alert    = UIAlertController(title: "Verify", message: "Please Enter the verification code to continue", preferredStyle: UIAlertControllerStyle.alert)
        verifyAction = UIAlertAction(title: "Verify", style: UIAlertActionStyle.default) { (action) in
            // Do verification and other stuffs
        }

        // Configures textfield properties and delegate
        alert.addTextField { (textField) in
            textField.placeholder = "Verification Code"
            textField.delegate    = self
        }

        // Disables the button
        verifyAction.isEnabled = false
        alert.addAction(verifyAction)
        self.present(alert, animated: true, completion: nil)
    }

    // Textfield delegate method for observing the text change
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool
    {
        // if text length is greater than 0 enables the button, else disables it
        let existingText = textField.text as NSString?
        if let replacedText = existingText?.replacingCharacters(in: range, with: string), replacedText.characters.count > 0
        {
            verifyAction.isEnabled = true
        }
        else
        {
            verifyAction.isEnabled = false
        }
        return true
    }
}

注意：我在发布代码之前写了这个答案，所以它不是基于你在问题中提供的代码。这是一个通用的答案，如果你想让我这么做，我会编辑答案。

Answer 2

通过使用默认警报控制器，点击任何警报操作按钮将关闭警报控制器。您可能必须创建自己的自定义视图/视图控制器并执行相应的操作或使用某些第三方库。

Answer 3

试试此代码，因为这对我来说很好用：

func createAlert() {
    // initializing
    let alertControler = UIAlertController(title: "Your Title",
                                           message: "Your message",
                                           preferredStyle: .Alert)
    // create actions
    let confirmAction = UIAlertAction(title: "Confirm", style: .Default, handler: {
        (action) -> Void in self.confirmAction()
    })

    let resendAction = UIAlertAction(title: "Resend", style: .Default, handler: {
        (action) -> Void in self.resendAction()
    })

    let cancelAction = UIAlertAction(title: "Cancel", style: .Default, handler: {
        (action) -> Void in self.dismissAlert()
    })

    // add actions
    alertControler.addAction(confirmAction)
    alertControler.addAction(resendAction)
    alertControler.addAction(cancelAction)

    self.presentViewController(alertControler, animated: true, completion: nil)
}

// initiate this func to your class
@objc private func dismissAlert() {
    self.dismissViewControllerAnimated(true, completion: nil)
}

@objc private func confirmAction() {
    // yuor action here
}

@objc private func resendAction() {
    // your action here
}

只需将self.createAlert（）实现为您的主要操作即可。或者实现＆＃34; self.dismissViewControllerAnimated（true，completion：nil）＆＃34;到你的cancelAction

不关闭视图的UIAlertController操作

3 个答案: