title: Swift - How to set initial value for NSUserDefaults
body: <p>I have a switch called <code>soundSwitch</code>, I'm saving the state of the button using an <code>userDefault</code> as such:</p>
  <pre><code>@IBAction func soundsChanged(sender: AnyObject) {
          if soundSwitch.on{
              defaults.setBool(true, forKey: &quot;SoundActive&quot;)
              print(&quot;Sound ON&quot;)
          }else{
              defaults.setBool(false, forKey: &quot;SoundActive&quot;)
              print(&quot;Sound OFF&quot;)
          }
      }
  </code></pre>
  <p>Currently, the actual default value is initially false when the user first launches the application.</p>
  <p>How can I implement the defaults to be true if the user launches the app and they haven't been configured yet.</p>
  <p>I've seen methods in <code>Objective-C</code>, but nothing in Swift. From what I've seen you can do it in the app delegate somehow, or in a <code>PList</code> file. How do I do either of those ones?</p>