Video.js

import React, { Component } from 'react';
import { View, StyleSheet, NativeModules, Platform } from 'react-native';
import { RtcEngine, AgoraView } from 'react-native-agora';
import Icon from 'react-native-vector-icons/MaterialIcons';
import { Actions } from 'react-native-router-flux';

const { Agora } = NativeModules;                  //Define Agora object as a native module

const {
  FPS30,
  AudioProfileDefault,
  AudioScenarioDefault,
  Adaptative,
} = Agora;                                        //Set defaults for Stream

class Video extends Component {
  constructor(props) {
    super(props);
    this.state = {
      peerIds: [],                                //Array for storing connected peers
      uid: Math.floor(Math.random() * 100),       //Generate a UID for local user
      appid: this.props.AppID,                    //Enter the App ID generated from the Agora Website
      channelName: this.props.ChannelName,        //Channel Name for the current session
      vidMute: false,                             //State variable for Video Mute
      audMute: false,                             //State variable for Audio Mute
      joinSucceed: false,                         //State variable for storing success
    };
    if (Platform.OS === 'android') {
      const config = {                            //Setting config of the app
        appid: this.state.appid,                  //App ID
        channelProfile: 0,                        //Set channel profile as 0 for RTC
        videoEncoderConfig: {                     //Set Video feed encoder settings
          width: 720,
          height: 1080,
          bitrate: 1,
          frameRate: FPS30,
          orientationMode: Adaptative,
        },
        audioProfile: AudioProfileDefault,
        audioScenario: AudioScenarioDefault,
      };
      RtcEngine.init(config);                     //Initialize the RTC engine
    }
  }

  componentDidMount() {
    RtcEngine.on('userJoined', (data) => {
      const { peerIds } = this.state;             //Get currrent peer IDs
      if (peerIds.indexOf(data.uid) === -1) {     //If new user has joined
        this.setState({
          peerIds: [...peerIds, data.uid],        //add peer ID to state array
        });
      }
    });
    RtcEngine.on('userOffline', (data) => {       //If user leaves
      this.setState({
        peerIds: this.state.peerIds.filter(uid => uid !== data.uid), //remove peer ID from state array
      });
    });
    RtcEngine.on('joinChannelSuccess', (data) => {                   //If Local user joins RTC channel
      RtcEngine.startPreview();                                      //Start RTC preview
      this.setState({
        joinSucceed: true,                                           //Set state variable to true
      });
    });
    RtcEngine.joinChannel(this.state.channelName, this.state.uid);  //Join Channel
    RtcEngine.enableAudio();                                        //Enable the audio
  }