title: cannot read property 'dispatch' of undefined in this.props.navigation.dispatch()
body: <p>I have to cutomize my drawer then I create a DrawerComponent with all items thas I need, I create a function with NavigationActions to dispatch my routes but it doesn't work. when I click on any item I have this error: cannot read property 'dispatch' of undefine </p>
  
  <pre><code>import {NavigationActions} from 'react-navigation';
  ...
  class DrawerComponent extends React.Component {
  
    navigateToScreen = (route) =&gt; () =&gt; {
      const navigateAction = NavigationActions.navigate({
        routeName: route
      });
      this.props.navigation.dispatch(navigateAction);
  }
  
  
    render()...
  ...
  ...
  
    &lt;TouchableOpacity
     style={Styles.centerContent}
     onPress= {this.navigateToScreen('Messages')}
  
    &gt;
     &lt;IconIonic name="ios-mail" size={60} color= '#fff'/&gt;
     &lt;View&gt;
      &lt;Text&gt;messages&lt;/Text&gt;
     &lt;/View&gt;
    &lt;/TouchableOpacity&gt;
  </code></pre>
  
  <p>In drawer</p>
  
  <pre><code>import { createStackNavigator, createDrawerNavigator, createAppContainer } from 'react-navigation';
  ...
  const DrawerNavigation = createDrawerNavigator({
      Home: { // entree (route name) : on peut la nommer comme on veut mais on prefere lui donner le meme nom que notre screen qu'on va afficher
        screen: HomeStackNavigation, // le screen qu'on va afficher IL DOIT ETRE UN STACK
      },
      Message: {
        screen: Messages,
      },
  },
  {
    drawerWidth: width*0.83,
    contentComponent: props =&gt; 
    {
      return(&lt;DrawerComponent/&gt;)
    },
    drawerPosition: 'left',
  },
  );
  </code></pre>
  
  <p>before that error, I had something like : undefined is not an object evaluating _this.props.navigation.dispatch()</p>