App.js

/**
 * Sample React Native App
 * https://github.com/facebook/react-native
 * @flow
 */

import React, { Component } from 'react';
import {
  Platform,
  StyleSheet,
  Text,
  View,
  TouchableOpacity
} from 'react-native';

import firebase from 'react-native-firebase';
import type, { RemoteMessage, Notification, NotificationOpen } from 'react-native-firebase';


const instructions = Platform.select({
  ios: 'Press Cmd+R to reload,\n' +
    'Cmd+D or shake for dev menu',
  android: 'Double tap R on your keyboard to reload,\n' +
    'Shake or press menu button for dev menu',
});

const notification = new firebase.notifications.Notification()
  .setNotificationId('notificationId')
  .setTitle('My notification title')
  .setBody('My notification body')
  .setData({
    key1: 'value1',
    key2: 'value2',
  });


// // Build a channel
// const channel = new firebase.notifications.Android.Channel('test-channel', 'Test Channel', firebase.notifications.Android.Importance.Max)
// .setDescription('My apps test channel');

// // Create the channel
// firebase.notifications().android.createChannel(channel);

type Props = {};
export default class App extends Component<Props> {

  componentDidMount() {

    firebase.messaging().hasPermission()
    .then(enabled => {
      if (enabled) {
        // user has permissions
        this.notificationDisplayedListener = firebase.notifications().onNotificationDisplayed((notification: Notification) => {
          // Process your notification as required
          // ANDROID: Remote notifications do not contain the channel ID. You will have to specify this manually if you'd like to re-display the notification.
          onNotification = (notification: Notification) => {
            notification.android.setChannelId(notification.data.channelId);
            firebase.notifications().displayNotification(notification);
          };
        });
        this.notificationListener = firebase.notifications().onNotification((notification: Notification) => {
            // Process your notification as required
        });

        this.notificationOpenedListener = firebase.notifications().onNotificationOpened((notificationOpen: NotificationOpen) => {
          // Get the action triggered by the notification being opened
          const action = notificationOpen.action;
          // Get information about the notification that was opened
          const notification: Notification = notificationOpen.notification;
      });

      firebase.notifications().getInitialNotification()
      .then((notificationOpen: NotificationOpen) => {
        if (notificationOpen) {
          // App was opened by a notification
          // Get the action triggered by the notification being opened
          const action = notificationOpen.action;
          // Get information about the notification that was opened
          const notification: Notification = notificationOpen.notification;
        }
      });

      } else {
        // user doesn't have permission
        firebase.messaging().requestPermission()
        .then(() => {
          // User has authorised
          this.notificationDisplayedListener = firebase.notifications().onNotificationDisplayed((notification: Notification) => {
            // Process your notification as required
            // ANDROID: Remote notifications do not contain the channel ID. You will have to specify this manually if you'd like to re-display the notification.
          });
          this.notificationListener = firebase.notifications().onNotification((notification: Notification) => {
              // Process your notification as required
          });
        })
        .catch(error => {
          // User has rejected permissions
        });
      }
    });
}

componentWillUnmount() {
  this.notificationDisplayedListener();
  this.notificationListener();
  this.notificationOpenedListener();
}

  render() {
    return (
      <View style={styles.container}>
        <Text style={styles.welcome}>
          Welcome to React Native!
        </Text>
        <TouchableOpacity
          style={{backgroundColor: 'cyan'}}
          onPress={()=>{
            firebase.notifications().displayNotification(notification);
            // firebase.auth()
            //   .signInAnonymouslyAndRetrieveData()
            //   .then(credential => {
            //     if (credential) {
            //       console.log('default app user ->', credential.user.toJSON());
            //     }
            //   });
          }}>
          <Text>Test</Text>
        </TouchableOpacity>
        <Text style={styles.instructions}>
          To get started, edit App.js
        </Text>
        <Text style={styles.instructions}>
          {instructions}
        </Text>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#F5FCFF',
  },
  welcome: {
    fontSize: 20,
    textAlign: 'center',
    margin: 10,
  },
  instructions: {
    textAlign: 'center',
    color: '#333333',
    marginBottom: 5,
  },
});