无法在AlertController中添加文本字段

Question

var textFD = UITextField.init()
var tempStr : String!
var datax = [Tasks]()
var tempArr = [NSManagedObject]()
override func viewDidLoad() {
    super.viewDidLoad()

    navigationItem.rightBarButtonItem = UIBarButtonItem.init(title: "Add", style: UIBarButtonItemStyle.plain, target: self, action:#selector(myTableViewController.addFunc))
    print("Hello")
     fetchData()
}
 func addFunc(){
    let alertO = UIAlertController.init(title: "Add", message: "Add what you want", preferredStyle: .alert)
    let saveAct=UIAlertAction.init(title: "Save", style: .default, handler:saveHandler)
    let cancelAct=UIAlertAction.init(title: "Cancel", style: .default, handler: nil)
    alertO.addAction(saveAct)
    alertO.addAction(cancelAct)
    alertO.addTextField(configurationHandler: { (textFD) in

        textFD.placeholder="Hey therer"

        print("textfd text1 is \n\n\n" ,textFD.text!)
        self.tempStr=textFD.text!
    })
    print("textfd text2 is \n\n\n",textFD.text! )
    self.present(alertO, animated: true, completion: nil)
    self.tableView.reloadData()
    self.tempStr=textFD.text!

}
func saveHandler(alert:UIAlertAction){
    print("textfd text3 is \n\n\n",textFD.text! )
    print("Value of tempStr \n\n ",tempStr)
    let taskX = Tasks(context: context)
    taskX.mydata = tempStr
    appDelegate.saveContext()
    self.tableView.reloadData()
    print("Value of tempStr \n\n ",tempStr)

}

When i click on button addFunc will call for alert and from an textfield over alert controller , later the text of textfield is stored in a string .

Alertcontroller, textfield over alert and placeholder of textfield is appear but when i trying to store textfield text into a string ( tempStr ) it can't stored !

Answer 1

try this

EDIT

func addFunc(){
    let alert = UIAlertController(title: "MESSAGE".localized, message: "ENTER_YOUR_MESSAGE".localized, preferredStyle: .alert)

            alert.addTextField { (textField) in
                // textField.placeholder = "Enter your message".localized
            }

            alert.addAction(UIAlertAction(title: "TITLE".localized, style: .default, handler: { (action:UIAlertAction!) in
                let textField = alert.textFields![0] // Force unwrapping because we know it exists.
                //print("Text field: \(String(describing: textField?.text))")

                if (textField.text?.characters.count)! > 0
                {
                    self.tempStr = textField.text

                }
                else
                {
                    print("empty text")
                }
            }))
            self.present(alert, animated: true, completion: nil)
}

Answer 2

Property textFD of this class is not the one that shows on alertO , The configurationHandler of textField just provide a closure to help user customize textField on UIAlertController.

To get text of textField on UIAlertController, first you need use property textFields of UIAlertController instance to get which textFiled you want, then use .text to get text of this textFiled.

Answer 3

alertO.addTextField(configurationHandler: { (textFD) in

    textFD.placeholder="Hey therer"

    print("textfd text1 is \n\n\n" ,textFD.text!)
    self.tempStr=textFD.text!
})

textfield is initializing with no text (blank default), tempStr is storing a blank value. you will have to save string on save action.

      let saveAct = UIAlertAction.init(title: "Save", style: .default, handler:{
            alertAction in
            let textField = alertO.textFields![0] as UITextField
            self.tempStr = textField.text
     })