title: How to clear the text field automatically
body: <p>I have a question about <code>UITextField()</code> in Swift. How can I clear the text in the text field when I click on it?</p>
  
  <p>My <code>textField.text = "0"</code>. I want to automatically remove the number "0" when I click on the text field:</p>
  
  <pre><code>import UIKit
  class ViewController: UIViewController, UITextFieldDelegate {
  
      @IBOutlet var lbltext: UILabel!
      @IBOutlet var scrolview1: UIScrollView!
      @IBOutlet var fi: UITextField!
      @IBOutlet var scrolviewus: UIScrollView!
      @IBOutlet var counterLabel: UILabel!
      override func viewDidLoad() {
          super.viewDidLoad()
          fi.text = "0"
         }
  
         override func didReceiveMemoryWarning() {
           super.didReceiveMemoryWarning()
           // Dispose of any resources that can be recreated.
         }
  
         @IBAction func button(sender: AnyObject) {
          lbltext.numberOfLines = 0
          lbltext.text! = lbltext.text! + "\n" + fi.text! + "\n" + "---  "
      }
   }
  </code></pre>