Firebase Messaging

Smart WebView integrates Firebase Cloud Messaging (FCM) to enable push notifications.

Setup

Refer to the Getting Started guide for the initial step of adding the google-services.json file to your project. This is mandatory for FCM.

How it Works

• Token Generation: The Firebase SDK automatically generates a unique registration token. The Firebase.java service listens for new tokens (onNewToken) and stores the latest token in SmartWebView.fcm_token. The Functions.fcm_token() method attempts to retrieve this and set it as a cookie (FCM_TOKEN=...) for your web application to access.
• Receiving Messages:
  • Foreground: Firebase.java’s onMessageReceived is triggered, and a notification is manually displayed.
  • Background/Closed: The Firebase SDK automatically handles displaying notifications sent with a notification payload.
• Handling Clicks: Notifications can include a data payload with a uri key. When the user taps the notification, the app opens and loads the specified uri. If no uri is provided, it defaults to the main ASWV_URL.

Sending Notifications

Use the Firebase Console or the FCM HTTP v1 API to send notifications.

Example POST Request (FCM HTTP v1 API):

// POST https://fcm.googleapis.com/v1/projects/YOUR_PROJECT_ID/messages:send
{
  "message": {
    "token": "DEVICE_REGISTRATION_TOKEN", // <-- Get this from the device
    "notification": {
      "title": "Your Notification Title",
      "body": "This is the main message body."
    },
    "android": {
      "notification": {
        "click_action": "OPEN_URI"
      }
    },
    "data": { // Custom data payload
      "uri": "https://your-website.com/specific-page",
      "nid": "unique_notification_id_123"
    }
  }
}

Headers:

• Content-Type: application/json
• Authorization: Bearer YOUR_OAUTH2_ACCESS_TOKEN

Customization

• Notification Channel: Customize the channel ID (SmartWebView.asw_fcm_channel) and names/descriptions in app/src/main/res/values/strings.xml. This is required for Android 8.0+.
• Notification Icon: Set the icon in Firebase.java via .setSmallIcon().
• Data Handling: Modify onMessageReceived in Firebase.java to process custom data payloads for more complex interactions.