title: Change the Text of Label in Swift
body: <p>I'm new with swift and this is the Hello World! application for me.
  I trying to change the text of Label when I press the button:</p>
  
  <pre><code>import UIKit
  </code></pre>
  
  <p>class ViewController: UIViewController {</p>
  
  <pre><code>@IBOutlet weak var txbFullname: UILabel!
  
  @IBAction func btnSubmit(sender: UIButton) {
      txbFullname.text = "hello"
  }
  </code></pre>
  
  <p>}</p>
  
  <p>I got the folloing error when I pressed the button in simulator :</p>
  
  <p><a href="https://i.stack.imgur.com/GGVxJ.png" rel="nofollow"><img src="https://i.stack.imgur.com/GGVxJ.png" alt="enter image description here"></a></p>
  
  <p>Can you help please !</p>
  
  <p>Xcode Version 8.0</p>
  
  <p>Thanks in advance.</p>