expo push notification is not working in standalone apk file but is working fine in expo go

Question

i have copied the whole code from expo's documentation. here is the code :

import { useState, useEffect, useRef } from 'react';
import { Text, View, Button, Platform } from 'react-native';
import * as Device from 'expo-device';
import * as Notifications from 'expo-notifications';
import Constants from 'expo-constants';


Notifications.setNotificationHandler({
  handleNotification: async () => ({
    shouldShowAlert: true,
    shouldPlaySound: false,
    shouldSetBadge: false,
  }),
});


// Can use this function below or use Expo's Push Notification Tool from: https://expo.dev/notifications
async function sendPushNotification(expoPushToken) {
  const message = {
    to: expoPushToken,
    sound: 'default',
    title: 'Original Title',
    body: 'And here is the body!',
    data: { someData: 'goes here' },
  };

  await fetch('https://exp.host/--/api/v2/push/send', {
    method: 'POST',
    headers: {
      Accept: 'application/json',
      'Accept-encoding': 'gzip, deflate',
      'Content-Type': 'application/json',
    },
    body: JSON.stringify(message),
  });
}

async function registerForPushNotificationsAsync() {
  let token;
  if (Device.isDevice) {
    const { status: existingStatus } = await Notifications.getPermissionsAsync();
    let finalStatus = existingStatus;
    if (existingStatus !== 'granted') {
      const { status } = await Notifications.requestPermissionsAsync();
      finalStatus = status;
    }
    if (finalStatus !== 'granted') {
      alert('Failed to get push token for push notification!');
      return;
    }
    token = await Notifications.getExpoPushTokenAsync({
      projectId: Constants.expoConfig.extra.eas.projectId,
    });
    console.log(token);
  } else {
    alert('Must use physical device for Push Notifications');
  }

  if (Platform.OS === 'android') {
    Notifications.setNotificationChannelAsync('default', {
      name: 'default',
      importance: Notifications.AndroidImportance.MAX,
      vibrationPattern: [0, 250, 250, 250],
      lightColor: '#FF231F7C',
    });
  }

  return token;
}

export default function App() {
  const [expoPushToken, setExpoPushToken] = useState('');
  const [notification, setNotification] = useState(false);
  const notificationListener = useRef();
  const responseListener = useRef();

  useEffect(() => {
    registerForPushNotificationsAsync().then(token => setExpoPushToken(token));

    notificationListener.current = Notifications.addNotificationReceivedListener(notification => {
      setNotification(notification);
    });

    responseListener.current = Notifications.addNotificationResponseReceivedListener(response => {
      console.log(response);
    });

    return () => {
      Notifications.removeNotificationSubscription(notificationListener.current);
      Notifications.removeNotificationSubscription(responseListener.current);
    };
  }, []);

  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'space-around' }}>
      <Text>Your expo push token: {expoPushToken}</Text>
      <View style={{ alignItems: 'center', justifyContent: 'center' }}>
        <Text>Title: {notification && notification.request.content.title} </Text>
        <Text>Body: {notification && notification.request.content.body}</Text>
        <Text>Data: {notification && JSON.stringify(notification.request.content.data)}</Text>
      </View>
      <Button
        title="Press to Send Notification"
        onPress={async () => {
          await sendPushNotification(expoPushToken);
        }}
      />
    </View>
  );
}

The problem lies with the statement Notifications.requestPermissionsAsync(). This function works only in expo go provided that its notifications are active. When we make standalone apk the status is always denied. It seems like this function is unable to perform its task in apk.

Answer 1

Expo notifications need to be integrated with Firebase Cloud Messaging in order to function in standalone Apk. I know this error must first seem like it is due to malfunction of this statement Notifications.requestPermissionsAsync(). But it is not. This function poses some problem in Android 13 because it does not show any prompt. But i tried it in other versions of android and it worked which proved that error is somewhere else. So I searched and found we need to link FCM(Firebase Cloud Messaging) to make it work. Here is the video link: Watch all four parts. You may face some problem while uploading server key of FCM to expo. You can do it by directing pushing it through terminal by following these commands: eas credentials > Android > (development, preview, production) according to your build profile > Push Notifications: Manage your FCM API Key > Upload an FCM API Key.