PickerTextField - Use PickerTextField when you want a list of choices in a UIPickerView displayed in place of the key board.

PickerTextField.swift

import UIKit
/**
 PickerTextField - Use PickerTextField when you want a list of choices in a UIPickerView displayed in place of the key board.
 
 - Note:
 Set it up by setting the choices to an array of strings.  These are the strings that will show up in the UIPickerView for the key board.
 - Note:
 You can set a block for onSelected for action when something is selected.
 - Note:
 The selectedTimeOut property can be set for the amount of time to wait after something is selected before ending the edit.
 */
public class PickerTextField: UITextField, UIPickerViewDelegate, UIPickerViewDataSource, UITextFieldDelegate {
    /// choices - Array of strings to show in the UIPickerView that comes up for the keyboard.
    public var choices = [String]()
    /// currentRow - current selected row
    public var currentRow:Int {
        get {
            return _currentRow
        }
    }
    /// selectedTimeOut - how long to wait till ending edit when something is selected
    public var selectedTimeOut:NSTimeInterval = 1.0
    
    required public init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        self._initialize()
    }
    /**
     onSelect is a callback one can set for when a value is selected
     
     set it to a function of type: (row:Int)->Void
    */
    public var onSelected:((row:Int)->Void)? = nil
    
    override public var text: String? {
        get {
            return super.text
        }
        set(value) {
            if let value = value {
                if self.choices[self.currentRow] != value {
                    if let index = self.choices.indexOf(value) {
                        self._currentRow = index
                    }
                }
                if let selected = self.onSelected {
                    selected(row: self.currentRow)
                }
            }
            super.text = value
        }
    }
    
    /// Private function for common initialization
    private func _initialize(){
        self._pickerView.delegate = self
        self._pickerView.dataSource = self
        
        self.inputView = self._pickerView
        self.delegate = self
        self.textAlignment = NSTextAlignment.Center
    }
    public func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
        return 1
    }
    public func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        return choices.count
    }
    public func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        if let timer = self._selectedTimer {
            timer.invalidate()
            self._selectedTimer = nil
        }
        if row < choices.count {
            return choices[row]
        }
        return "UNKNOWN"
    }
    public func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        self._currentRow = row
        self.text = choices[row]
        if let timer = self._selectedTimer {
            timer.invalidate()
            self._selectedTimer = nil
        }
        self._selectedTimer = NSTimer.scheduledTimerWithTimeInterval(self.selectedTimeOut, target: self, selector: #selector(_selectedTimerFired), userInfo: nil, repeats: false)
    }
    public func textFieldDidBeginEditing(textField: UITextField) {
        if let select = choices.indexOf(textField.text!) {
            self._pickerView.selectRow(select, inComponent: 0, animated: false)
        }
    }
    
    private var _pickerView:UIPickerView = UIPickerView()
    internal var _selectedTimer:NSTimer? = nil
    @objc private func _selectedTimerFired() -> Void {
        self.endEditing(false)
    }
    private var _currentRow = 0
}