@react-native-firebase/messaging/plugin/src/android/setupFirebaseNotifationIcon.ts

React Native Firebase - React Native Firebase provides native integration of Firebase Cloud Messaging (FCM) for both Android & iOS. FCM is a cost free service, allowing for server-device and device-device communication. The React Native Firebase Messaging

import { ConfigPlugin, withAndroidManifest } from '@expo/config-plugins';
import { ManifestApplication } from '@expo/config-plugins/build/android/Manifest';
import { ExpoConfig } from '@expo/config-types';
import { PluginConfigType } from '../pluginConfig';

/**
 * Determine whether a ManifestApplication has an attribute.
 */
const hasMetaData = (application: ManifestApplication, metaData: string) => {
  return application['meta-data']?.some(item => item['$']['android:name'] === metaData);
};

/**
 * Create `com.google.firebase.messaging.default_notification_icon` and `com.google.firebase.messaging.default_notification_color`
 */
export const withExpoPluginFirebaseNotification: ConfigPlugin<PluginConfigType | undefined> = (
  config,
  props,
) => {
  return withAndroidManifest(config, async config => {
    // Add NS `xmlns:tools to handle boundary conditions.
    config.modResults.manifest.$ = {
      ...config.modResults.manifest.$,
      'xmlns:tools': 'http://schemas.android.com/tools',
    };

    const application = config.modResults.manifest.application![0];
    setFireBaseMessagingAndroidManifest(config, application, props);
    return config;
  });
};

// Helper function to get notification icon and color from plugin props, expo-notifications, or config.notification
const getNotificationConfig = (config: ExpoConfig, props?: PluginConfigType) => {
  // 1. Check props passed directly to @react-native-firebase/messaging plugin
  if (props?.android?.notificationIcon) {
    return {
      icon: props.android.notificationIcon,
      color: props.android.notificationColor,
    };
  }

  // 2. Check expo-notifications plugin
  if (config.plugins) {
    const expoNotificationsPlugin = config.plugins.find(
      plugin => Array.isArray(plugin) && plugin[0] === 'expo-notifications',
    );

    if (expoNotificationsPlugin && Array.isArray(expoNotificationsPlugin)) {
      const pluginConfig = expoNotificationsPlugin[1];
      if (pluginConfig && typeof pluginConfig === 'object') {
        return {
          icon: pluginConfig.icon,
          color: pluginConfig.color,
        };
      }
    }
  }

  /**
   * @deprecated
   * Get notification config from config.notification
   * Will be removed in the future as `expo-notifications` plugin is the recommended way to configure notifications.
   */
  // @ts-ignore - config.notification deprecated in Expo 54 / removed in Expo 55+, but still useful for people
  if (config.notification) {
    return {
      // @ts-ignore - config.notification deprecated in Expo 54 / removed in Expo 55+, but still useful for people
      icon: config.notification.icon,
      // @ts-ignore - config.notification deprecated in Expo 54 / removed in Expo 55+, but still useful for people
      color: config.notification.color,
    };
  }

  return { icon: undefined, color: undefined };
};

export function setFireBaseMessagingAndroidManifest(
  config: ExpoConfig,
  application: ManifestApplication,
  props?: PluginConfigType,
) {
  const { icon, color } = getNotificationConfig(config, props);
  if (!icon) {
    // This warning is important because the notification icon can only use pure white on Android. By default, the system uses the app icon as the notification icon, but the app icon is usually not pure white, so you need to set the notification icon
    // eslint-disable-next-line no-console
    console.warn(
      'For Android 8.0 and above, it is necessary to set the notification icon to ensure correct display. Otherwise, the notification will not show the correct icon. For more information, visit https://docs.expo.dev/versions/latest/config/app/#notification',
    );
  }

  // Defensive code
  application['meta-data'] ??= [];

  const metaData = application['meta-data'];

  if (
    icon &&
    !hasMetaData(application, 'com.google.firebase.messaging.default_notification_icon')
  ) {
    // Expo will automatically create '@drawable/notification_icon' resource if you specify config.notification.icon.
    metaData.push({
      $: {
        'android:name': 'com.google.firebase.messaging.default_notification_icon',
        'android:resource': '@drawable/notification_icon',
      },
    });
  }

  if (
    color &&
    !hasMetaData(application, 'com.google.firebase.messaging.default_notification_color')
  ) {
    metaData.push({
      $: {
        'android:name': 'com.google.firebase.messaging.default_notification_color',
        'android:resource': '@color/notification_icon_color',
        // @react-native-firebase/messaging will automatically configure the notification color from the 'firebase.json' file, setting 'tools:replace' = 'android:resource' to overwrite it.
        // @ts-ignore
        'tools:replace': 'android:resource',
      },
    });
  }

  return application;
}