title: Example for login screen modally based on storyboard
body: <p>I am learning ios/ xcode and at a roadblock.</p>
  
  <p>I have a tabbarcontroller+navigation based design. I need to present a login screen if user is not logged in. Here is the basic heirarchy. The login page needs a navigationBar (as the tutorial I followed puts a "Go" button on the bar. </p>
  
  <pre><code>LoginController: (LTController.h,.m)
  
  Main View:TabBarController&gt;
                     NavigationController&gt;View1&gt;View1a
                     NavigationController&gt;View2
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/PJVRa.png" alt="Storyboard layout"></p>
  
  <p>I read lot of posts here on modal view, delegate method, etc. Most of them are code snippets which unfortunately are a bit over the head for my beginner level.</p>
  
  <p>Would appreciate a simple explanation as to how to achieve this. Espacially a note on which files needs changes would be great. </p>
  
  <p>thanks</p>