App.js

import PushNotification from "react-native-push-notification";
import Firebase from '@react-native-firebase/app';
import React, {Component} from 'react';
import { View, Text } from 'react-native';
class App extends Component {
    componentDidMount() {
        Firebase.initializeApp(this);
        // Must be outside of any component LifeCycle (such as `componentDidMount`).
        PushNotification.configure({
            // (optional) Called when Token is generated (iOS and Android)
            onRegister: function (token) {
                console.log("TOKEN:", token);
            },

            // (required) Called when a remote is received or opened, or local notification is opened
            onNotification: function (notification) {
                console.log("NOTIFICATION:", notification);

                // process the notification

                // (required) Called when a remote is received or opened, or local notification is opened
                notification.finish(PushNotificationIOS.FetchResult.NoData);
            },

            // (optional) Called when Registered Action is pressed and invokeApp is false, if true onNotification will be called (Android)
            onAction: function (notification) {
                console.log("ACTION:", notification.action);
                console.log("NOTIFICATION:", notification);

                // process the action
            },

            // (optional) Called when the user fails to register for remote notifications. Typically occurs when APNS is having issues, or the device is a simulator. (iOS)
            onRegistrationError: function (err) {
                console.error(err.message, err);
            },

            // IOS ONLY (optional): default: all - Permissions to register.
            permissions: {
                alert: true,
                badge: true,
                sound: true,
            },

            // Should the initial notification be popped automatically
            // default: true
            popInitialNotification: true,

            /**
             * (optional) default: true
             * - Specified if permissions (ios) and token (android and ios) will requested or not,
             * - if not, you must call PushNotificationsHandler.requestPermissions() later
             * - if you are not using remote notification or do not have Firebase installed, use this:
             *     requestPermissions: Platform.OS === 'ios'
             */
            requestPermissions: true,
        });
    }

    render() {
        return (
            <View style={{ flex: 1, justifyContent: 'center', alignItems: 'center', backgroundColor: '#F68989' }}>
                <Text style={{ fontSize: 20, color: '#0E185F' }}>
                    Firebase Messaging - PUSH Notification
                </Text>
            </View>
        );
    }

};
export default App;