title: Tab navigator icons in React Navigation
body: <p>I'm using react-navigation v2 and react native vector icons.</p>
  
  <p>I'm trying to add an icon in a react native tab navigator. </p>
  
  <p>The icon shows up if its not in the tab navigator. The icon is not showing up in the tab navigator and I can't find a solid example of how to add an icon in a tab navigator.</p>
  
  <pre class="lang-js prettyprint-override"><code>import React, { Component } from 'react';
  import { StyleSheet, Text, View } from 'react-native';
  
  import { createMaterialTopTabNavigator } from 'react-navigation'
  
  import Home from '../HomePage.js'
  import Profile s from '../ProfilePage.js'
  
  import Icon from 'react-native-vector-icons/FontAwesome';
  
  export const Tabs = createMaterialTopTabNavigator(
    {
      HomePage: {
        screen: Home,
  
        navigationOptions: {
          tabBarLabel:"Home Page",
          tabBarIcon: ({ tintColor }) =&gt; (
            &lt;Icon name="home" size={30} color="#900" /&gt;
          )
        },
      },
      ProfilePage: {
        screen: Profile,
        navigationOptions: {
          tabBarLabel:"Profile Page",
          tabBarIcon: ({ tintColor }) =&gt; (
            &lt;Icon name="users" size={30} color="#900" /&gt;
          )
        }
      },
    },
  
    {
      order: ['HomePage', 'ProfilePage'],
      tabBarOptions: {
        activeTintColor: '#D4AF37',
        inactiveTintColor: 'gray',
        style: {
          backgroundColor: 'white',
        }
      },
    },
  )
  </code></pre>