是否有可能從Swift中的UITextField中獲得UIPickerView和UIDatePicker？

Question

我是新來的Swift，請耐心等待。

首先，讓我解釋一下我的應用程序佈局：

我有一個文本字段在屏幕上，有一個標籤和一個按鈕。我詢問用戶3個問題 - 使用「標籤」顯示這些問題，並且每當用戶按下下一個「按鈕」時（問題從數組中填充），就會出現下一個問題。

其中一個問題需要填充Picker View（因此用戶可以選擇一個選項）。 其中一個問題使用普通鍵盤。 而我需要使用日期選取器的最後一個問題。

這可能嗎？如果是這樣，你能告訴我如何將它添加到我的代碼下面嗎？

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. 

    } 

    } 

感謝您的幫助！

尼克

NEW下面的代碼（從2015年4月6日）：

類的ViewController：UIViewController中，UITextFieldDelegate，UIPickerViewDataSource，UIPickerViewDelegate基於currentQuestionIndex {

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

你可以將UIPickerView或UIDatePicker添加到您的UITextField例如

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

編輯：更多的解釋

起初，符合UITextFieldDelegate和實施textFieldDidBeginEditing(:) 因爲你想獲得通知您必須實現該方法時的UITextField實例獲得第一個響應狀態

而且，將UITextField實例的delegate屬性設置爲self或者您想要放置並實施的任何實例/對象textFieldDidBeginEditing(:)

然後編寫代碼

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 
    } 
} 

記住，當你想添加另一種觀點認爲，以你的UIPopoverViewController刪除添加的視圖。

編輯：添加真實世界中的實現

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) 
      } 
     } 
}