title: React Native - Identify the active screen. Drawer navigator
body: <p>I am using stack navigator inside the drawer navigator. What I want to do is, I need to know the activeItem (the active screen), so as to display it as active. </p>
  
  <blockquote>
    <p>StackNavigator</p>
  </blockquote>
  
  <pre><code>const stackNav = StackNavigator({
    homeComponent: { screen: HomeScreen },
    serviceScreen: { screen: ServiceScreen },
    serviceDetailScreen: { screen: ServiceDetailScreen },
    selectVehicleScreen: { screen: SelectVehileScreen },
    addEditVehicle: { screen: AddVehicle },
    dateTimeScreen: { screen: DateTimeScreen },
    reviewScreen: { screen: ReviewScreen },
    notesScreen: { screen: NotesScreen },
  }, {
    headerMode: 'none'
  }); 
  </code></pre>
  
  <blockquote>
    <p>DrawerNavigator</p>
  </blockquote>
  
  <pre><code>const DrawerStack = DrawerNavigator({
    appointment: {
      screen: stackNav,
    },
  }, {
    headerMode: 'none',
    gesturesEnabled: false,
    contentComponent: DrawerContainer
  
  });
  
  export default DrawerStack;
  </code></pre>