title: Change icon color in react-navigation header bar
body: <p>I just started developing in React-Native and also seems to move on smoothly just that when I try changing the color of an icon in the header bar, it still remains it's default color which is black. any help will be appreciated.</p>
  
  <pre><code>import {Platform, StyleSheet, Text, View, TouchableOpacity, Image, Dimensions} from 'react-native';
  import {Container, Content, List, ListItem, Left, Body, Icon, Button, Thumbnail, Form, Item, Label, Input, Right} from 'native-base';
  
  static navigationOptions = ({ navigation }) =&gt; {
      return {
          title: '',
          headerStyle: {backgroundColor: 'purple'},
          headerTintColor: '#fff',
          headerTitleStyle: {fontWeight: 'bold'},
          headerLeft:(
              &lt;TouchableOpacity onPress={() =&gt; navigation.toggleDrawer()} 
                  style={{padding:10}}&gt;
                  &lt;Icon color="#fff" size={27} name='ios-menu'/&gt;
              &lt;/TouchableOpacity&gt;
          )
      };
  }
  </code></pre>