Question

我是Swift的新手所以请耐心等待。

首先，让我解释一下我的应用布局：

我在屏幕上有一个文本字段，带有标签和按钮。我问用户3个问题 - 这些问题是使用“标签”显示的，每次用户按下“下一步”按钮时，都会显示下一个问题。（问题从数组中填充）。

其中一个问题需要填充Picker View（因此用户可以选择一个选项）。其中一个问题使用普通键盘。我需要使用日期选择器的最后一个问题。

这可能吗？如果是这样，你能告诉我如何将它添加到我的代码中吗？

let questions = ["What is your title?", "What is your full name?", "When were you born?"]

var currentQuestionIndex = 0

let placeholder = ["Title", "Full name", "Date of birth"]

var currentPlaceholderIndex = 0

@IBAction func nextButton(sender: AnyObject) {

    textField.hidden = false
    textField.placeholder = placeholder[currentPlaceholderIndex]
    barImage.hidden = false

    // Reset text field to have no text
    textField.text = ""


    questionLabel.text = questions[currentQuestionIndex]

    // Displays the questions in array
    if currentQuestionIndex < questions.count {
        ++currentQuestionIndex

        // Displays the placeholder text in the textfield
        if currentPlaceholderIndex < placeholder.count {
            ++currentPlaceholderIndex

        }

        buttonLabel.setTitle("Next", forState: UIControlState.Normal)


    }

    else {

       //Add some logic here to run whenever the user has answered all the questions.

    }

  }

感谢您的帮助！

尼克

以下新代码（自2015年4月6日起）：

类ViewController：UIViewController，UITextFieldDelegate，UIPickerViewDataSource，UIPickerViewDelegate {

var pickerData = ["Mr", "Mrs", "Miss", "Ms", "Doctor"]

var questions = ["What is your title?", "What is your name?", "What is your DOB?"]

var currentQuestionIndex = 0

var datePickerView:UIDatePicker = UIDatePicker()
var pickerView:UIPickerView = UIPickerView()

@IBOutlet var buttonLabel: UIButton!

@IBOutlet var questionsLabel: UILabel!

@IBOutlet var textField: UITextField!

@IBAction func textFieldEditing(sender: UITextField) {

    datePickerView.datePickerMode = UIDatePickerMode.Date
    sender.inputView = datePickerView
    datePickerView.addTarget(self, action: Selector("datePickerValueChanged:"), forControlEvents: UIControlEvents.ValueChanged)
}

func datePickerValueChanged(sender: UIDatePicker) {
    var dateformatter = NSDateFormatter()
    dateformatter.dateStyle = NSDateFormatterStyle.LongStyle
    textField.text = dateformatter.stringFromDate(sender.date)
}

@IBAction func nextButton(sender: UIButton) {

    textField.text = ""
    textField.hidden = false
    buttonLabel.setTitle("Next", forState: UIControlState.Normal)
    questionsLabel.text = questions[currentQuestionIndex]

    if currentQuestionIndex < questions.count {

        currentQuestionIndex++ 
    }

    else {
        //println("questions are complete")
    }
}

func textFieldDidBeginEditing(textField: UITextField) {

    switch currentQuestionIndex {

    case 0:
        self.view.addSubview(datePickerView)

    case 2:
        self.view.addSubview(pickerView)
    default:
        println("Test")
    }
}


override func viewDidLoad() {
    super.viewDidLoad()
    buttonLabel.setTitle("Start", forState: UIControlState.Normal)
    textField.hidden = true
    questionsLabel.text = ""
    textField.delegate = self
    pickerView.delegate = self
    pickerView.dataSource = self


    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func textFieldShouldReturn(textField: UITextField) -> Bool {
    textField.resignFirstResponder()
    return true
}

override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
    self.view.endEditing(true)

}


func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {

return 1
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {

return pickerData.count

}

func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
return pickerData[row]

}

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {

textField.text = pickerData[row]
pickerView.hidden = true

}

}

Answer 1

根据currentQuestionIndex，您可以向UIPickerView个实例添加UIDatePicker或UITextField

switch currentQuestionIndex {
case 0: 
  // TODO: Add UIPickerView
case 2:
  // TODO: Add UIDatePicker
}

编辑：更多解释

首先，遵守UITextFieldDelegate并实施textFieldDidBeginEditing(:) 您必须实现该方法，因为您希望在UITextField实例获得第一响应者状态时获得通知

另外，将UITextField实例的delegate属性设置为self，或者将要放置的实例/对象设置为textFieldDidBeginEditing(:)

然后编写此代码

func textFieldDidBeginEditing(_ textField: UITextField) {
  switch currentQuestionIndex {
    case 0: 
      // TODO: Add UIPickerView
      // Add it for example at the bottom your view self.view.addSubview(pickerViewInstance)
      // or add it as the subview of UIPopoverController instance that is added to your UITextField instance 
    case 2:
      // TODO: Add UIDatePicker
      // Add it for example at the bottom your view self.view.addSubview(datePickerInstance)
      // or add it as the subview of UIPopoverController instance that is added to your UITextField instance 
  }
}

当您想要向UIPopoverViewController添加另一个视图时，请记住删除添加的视图。

编辑：添加真实世界的实现

class NewCaseViewController : UIViewController {
    . . .

    @IBOutlet weak var textField: UITextField // TODO: Initialize it properly in designated initializer
    var popoverController: UIPopoverController! // TODO: Initialize it

    . . .
}


class PopoverContentManager : UIViewController {
    . . .

    var pickerView: UIPickerView // TODO: Initialize it properly
    var datePicker: UIDatePicker // TODO: Initialize it properly

    . . .
}

extension NewCaseViewController : UITextFieldDelegate {
    func textFieldBeginEditing(_ textField: UITextField) {
        println(__FUNCTION__)

        var popover = PopoverContentManager()

        switch self.currentQuestionIndex {
            case 0:
                popover.datePicker.hidden = true

                self.popoverController = init(contentViewController: popOver)

                self.popoverController.presentPopoverFromRect(self.textField.bounds, inView: self.textField, permittedArrowDirections: UIPopoverArrowDirectionDown, animated: true)

                self.popoverController.popoverContentSize = CGSizeMake(120, 90)
            case 1:
                popover.pickerView.hidden = true

                self.popoverController = init(contentViewController: popOver)

                self.popoverController.presentPopoverFromRect(self.textField.bounds, inView: self.textField, permittedArrowDirections: UIPopoverArrowDirectionDown, animated: true)

                self.popoverController.popoverContentSize = CGSizeMake(120, 90)
            }
        }
}

是否可以从Swift中的同一个UITextField获得UIPickerView和UIDatePicker？

1 个答案: