从Swift中的iOS警报中的TextField获取输入值

我试图做一个警告消息输入，然后从输入获取值。我发现很多好的教程如何使输入文本字段。但我无法从警报中获取值。

为Swift 3更新：

//1. Create the alert controller.
let alert = UIAlertController(title: "Some Title",message: "Enter a text",preferredStyle: .alert)

//2. Add the text field. You can configure it however you need.
alert.addTextField { (textField) in
    textField.text = "Some default text"
}

// 3. Grab the value from the text field,and print it when the user clicks OK.
alert.addAction(UIAlertAction(title: "OK",style: .default,handler: { [weak alert] (_) in
    let textField = alert.textFields![0] // Force unwrapping because we kNow it exists.
    print("Text field: \(textField.text)")
}))

// 4. Present the alert.
self.present(alert,animated: true,completion: nil)

Swift 2.x

假设您想要在iOS上显示动作快讯：

//1. Create the alert controller.            
var alert = UIAlertController(title: "Some Title",preferredStyle: .Alert)

//2. Add the text field. You can configure it however you need.
alert.addTextFieldWithConfigurationHandler({ (textField) -> Void in
    textField.text = "Some default text."
})

//3. Grab the value from the text field,and print it when the user clicks OK. 
alert.addAction(UIAlertAction(title: "OK",style: .Default,handler: { [weak alert] (action) -> Void in
    let textField = alert.textFields![0] as UITextField
    println("Text field: \(textField.text)")
}))

// 4. Present the alert.
self.presentViewController(alert,completion: nil)