title: Material UI text input field inside Appbar not working
body: <p>I am trying to insert two text input fields for username and password at the right of Appbar with following code. But it doesn't give the any output.</p>
  
  <pre><code>const AppBarExampleIconMenu = () =&gt; ( &lt; AppBar title = { &lt; span style = { styles.title } &gt; Test &lt; /span&gt;}
              iconElementLeft = { &lt; IconButton &gt; &lt; NavigationClose / &gt; &lt; /IconButton&gt;}
                  iconElementRight = { &lt; div &gt;
                      &lt; TextField
                      hintText = "UserName" / &gt;
                       &lt; TextField
                      hintText = "PassWord" / &gt;
                      &lt; /div&gt;
                  }
  
                  /&gt;
              );
  </code></pre>