ios Swift 2：扩展名-带有文本字段的警报

Question

i'm trying to create a function using a uialertcontroller with textfield using extension uialertcontroller

this is my code :

extension UIAlertController{

class func AlertWithTextField(here: String, message1 : String) -> UIAlertController{

    var alertController:UIAlertController?
    alertController = UIAlertController(title: here,
        message: message1,
        preferredStyle: .Alert)

    alertController!.addTextFieldWithConfigurationHandler(
        {(textField: UITextField!) in
            textField.placeholder = "Ex: 1"
            textField.textAlignment = .Center
            textField.delegate = self
            textField.keyboardType = UIKeyboardType.NumberPad
    })
    let action = UIAlertAction(title: "Submit",
        style: UIAlertActionStyle.Default,
        handler: {[weak self]
            (paramAction:UIAlertAction!) in
            if let textFields = alertController?.textFields{
                let theTextFields = textFields as! [UITextField]
                let enteredText = theTextFields[0].text
                print("\n\(enteredText)") }
        })
    let action2 =  UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler: nil)
    alertController?.addAction(action)
    alertController?.addAction(action2)

}}

okay, i have problem with the words "self", and i can't found solution for them, what could be the solution for this problem ??

Answer 1

For your first self problem, i would suggest you do something like this

    class func AlertWithTextField(here: String, message1 : String, delegate:UITextFieldDelegate?) -> UIAlertController{

    var alertController:UIAlertController?
    alertController = UIAlertController(title: here,
                                        message: message1,
                                        preferredStyle: .Alert)

    alertController!.addTextFieldWithConfigurationHandler(
        {(textField: UITextField!) in
            textField.placeholder = "Ex: 1"
            textField.textAlignment = .Center
            textField.delegate = delegate
            textField.keyboardType = UIKeyboardType.NumberPad
    })
    let action = UIAlertAction(title: "Submit",
                               style: UIAlertActionStyle.Default,
                               handler: {(paramAction:UIAlertAction!)->Void in
                                if let textFields = alertController?.textFields {
                                    let theTextFields = textFields
                                    let enteredText = theTextFields[0].text
                                    print("\n\(enteredText)") }
        })
    let action2 =  UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler: nil)
    alertController?.addAction(action)
    alertController?.addAction(action2)
    return alertController!
}

You can accept a UITextFieldDelegate object in your static methods and assign it ti the delegate and for your second problem you are declaring weak self but not using it in the closure so just remove that and your code should work fine.