title: React Native Dimensions iOS Change Event Doesn't Trigger
body: <p>I have a very simple event listener in my componentDidMount to listen for changes to the Dimensions, this never fires in my iOS simulator on iPhone (multiple models) but it does fire on the iPad Simulator and works fine in Android.</p>
  
  <pre><code>componentDidMount() {
  
      Dimensions.addEventListener( 'change', () =&gt;
         {
           this.getOrientation();
         });
  
  }
  </code></pre>
  
  <pre class="lang-js prettyprint-override"><code>getOrientation = () =&gt; {
    alert("Trigger Called"); // never fires in iPhone Simulator, but works on iPad Simulator and Android
  
    if (Dimensions.get("screen").width &lt; Dimensions.get("screen").height) {
      this.setState({ screenOrientation: "portrait" });
    } else {
      this.setState({ screenOrientation: "landscape" });
    }
  };
  </code></pre>
  
  <p>Am I doing something wrong? I also tried using EXPO Orientation but had the exact same problem. </p>
  
  <p>Thanks</p>