title: react-native-navigation drawer not opening
body: <p>Clicking on the navbar button the drawer is not opening. 
  Here is code i have used for button press</p>
  
  <pre><code>if (event.type === 'NavBarButtonPress') {
          if (event.id === 'sideDrawerToggle') {
              this.props.navigator.toggleDrawer({
                  side: 'left',
                  animated: true,
              });
          }
      }
  </code></pre>
  
  <p>Here is the drawer set up</p>
  
  <pre><code>Navigation.startTabBasedApp({
          tabs: [
              {
                  label: 'Find Place',
                  screen: 'places.FindPlace',
                  title: 'Find Place', 
                  icon: source[0],
                  navigatorButtons: {
                      leftButtons: [
                          {
                              icon : source[2],
                              title : 'Menu',
                              id: 'sideDrawerToggle'
                          }
                      ]
                  }
              },
              {
                  label: 'Share Place', 
                  screen: 'places.SharePlace', 
                  title: 'Share Place', 
                  icon: source[1],
                  navigatorButtons: {
                      leftButtons: [
                          {
                              icon: source[2],
                              title: 'Menu',
                              id: 'sideDrawerToggle'
                          }
                      ]
                  }
              }
          ],
          drawer: {
              left: { 
                  screen: 'places.SideDrawer'
              }
          }
      });
  </code></pre>
  
  <p>And this is what my drawer looks like </p>
  
  <pre><code>    import React, {Component} from 'react';
  import {View, Text, Dimensions} from 'react-native';
  
  
  class SideDrawer extends Component {
      render() {
          return(
              &lt;View style={[
                  styles.container,
                  {width: Dimensions.get('window').width * 0.8}
              ]}&gt;
                  &lt;Text&gt;Drawer&lt;/Text&gt;
              &lt;/View&gt;
          );
      }
  }
  
  const styles = {
      container: {
          backgroundColor : 'white',
          paddingTop: 22,
          flex: 1
      }
  };
  
  
  export default SideDrawer;
  </code></pre>
  
  <p>By searching a lot i found that giving a fixed width to drawer solves the problem. But its not solving in my case. I don't know what is wrong with the code, It was working fine. </p>