AppNavigator.js

import React, { Component } from 'react'
import {
  Navigator,
  View,
  BackAndroid
} from 'react-native'

import {
  Drawer
} from 'native-base'

import SideBar from './SideBar'
import LoginScreen from '../screens/LoginScreen'
import HomeScreen from '../screens/HomeScreen'
import ClientScreen from '../screens/ClientScreen'

export default class AppNavigator extends Component {
  constructor(props, context) {
    super(props, context)

    Firebase.init()

    this.state = {
      userLoaded: false,
      initialView: 'login',
      drawerDisabled: true
    }

  }

  componentWillMount() {
    let self = this

    BackAndroid.addEventListener('hardwareBackPress', () => {
      if (self._navigator.getCurrentRoutes().length === 1) {
        return false
      }

      self._navigator.pop()
      return true
    })

  }

  _setStateFrag(frag) {
    this.setState(frag)
  }

  _drawerActive(status) {
    this.setState = ({
      drawerDisabled: status
    })
  }

  _renderScene(route, navigator) {
    switch(route.id) {
      case 'login':
        return <LoginScreen 
                  navigator={navigator}
                  route={route}
                  emitter={_emitter}
                />
      case 'home':
        return <HomeScreen 
                  navigator={navigator} 
                  route={route} 
                  emitter={_emitter} 
                  setParentState={this._setStateFrag} 
                />
      case 'client':
        return <ClientScreen 
                navigator={navigator} 
                route={route} />
      default:
        break
    }
  }

  _configureScene(route, routeStack) {
    switch (route.id) {
      default:
        return Navigator.SceneConfigs.FloatFromBottomAndroid
    }
  }

  render() {
    return (
      <Drawer
        ref={(ref) => this._drawer = ref}
        content={ <SideBar navigator={this._navigator}/>}
        tapToClose={true}
        disabled={this.state.drawerDisabled}
      >
        <Navigator
          ref={(ref)=> this._navigator = ref}
          initialRoute={{id: this.state.initialView}}
          configureScene={this._configureScene}
          renderScene={this._renderScene.bind(this)}
        />
      </Drawer>
    )
  }
}