完成编辑后，在UIpickerview中保存该值

Question

我需要帮助4号。

1. 选择UITextField并显示UIPickerView（检查）
2. 选择UIPickerView中的值并显示在UITextfield（检查）
中
3. 点击屏幕并从UITextField移开焦点，UIPickerView消失（检查）
4. 点击UITextfield，它会在UITextField中显示所选的值，但UIPickerView会回到起始点（第0行）。

这是我的代码：

 @IBAction func textFieldEditing(sender: UITextField){
    var numberPicker:UIPickerView = UIPickerView()
    var row:Int = 0
    numberPicker.delegate = self
    desiredText?.inputView = numberPicker
    numberPicker.selectRow(79, inComponent: 0, animated: true)
    //desiredText?.text = pickOption[79]
}


func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int{
    return 1
}

func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int{
    return pickOption.count
}

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

func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int){
    desiredText!.text = pickOption[row]
}