Added FID-based registration snippets for FCM

messaging/app/src/main/java/com/google/firebase/example/messaging/MainActivity.java

@@ -141,4 +141,20 @@ private void askNotificationPermission() {
         }
     }
     // [END ask_post_notifications]
+
+    private void registerFid() {
+        // [START register_fid]
+        // Trigger manual registration if auto-initialization is turned off.
+        // Consider calling this every time the app starts to guarantee sync status.
+        FirebaseMessaging.getInstance().register()
+            .addOnCompleteListener(this, task -> {
+                if (!task.isSuccessful()) {
+                    // Registration failed. Consider retrying the registration with exponential backoff.
+                    Log.w(TAG, "Failed to register with Firebase Cloud Messaging", task.getException());
+                }
+                // Success! The Firebase Installation ID can be used to target messages to this app
+                // instance and will be delivered asynchronously to your onRegistered() callback.
+            });
+        // [END register_fid]
+    }
 }

messaging/app/src/main/java/com/google/firebase/example/messaging/MyFirebaseMessagingService.java

@@ -136,4 +136,24 @@ public Result doWork() {
             return Result.success();
         }
     }
+
+    // [START on_fid_registered]
+    /**
+     * There are three scenarios when `onRegistered` is called:
+     * 1) Every time a manual `register()` call finishes successfully
+     * 2) Whenever the FID is changed and the app is re-registered with FCM via the new FID
+     * 3) Automatically on the first app startup or routine sync when auto-initialization is enabled.
+     * Under #2, there are three scenarios when the existing FID is changed:
+     * A) App is restored to a new device
+     * B) User uninstalls/reinstalls the app
+     * C) User clears app data
+     */
+    @Override
+    public void onRegistered(@NonNull String installationId) {
+        Log.d(TAG, "Registered installation ID: " + installationId);
+
+        // Send the Firebase Installation ID to your app server.
+        sendRegistrationToServer(installationId);
+    }
+    // [END on_fid_registered]
 }

messaging/app/src/main/java/com/google/firebase/example/messaging/kotlin/MainActivity.kt

@@ -9,9 +9,9 @@ import android.widget.Toast
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AppCompatActivity
 import androidx.core.content.ContextCompat
+import com.google.firebase.Firebase
 import com.google.firebase.firestore.FieldValue
 import com.google.firebase.firestore.firestore
-import com.google.firebase.Firebase
 import com.google.firebase.messaging.messaging
 import com.google.firebase.messaging.remoteMessage
 import kotlinx.coroutines.launch
@@ -20,135 +20,150 @@ import java.util.concurrent.atomic.AtomicInteger
 
 class MainActivity : AppCompatActivity() {
 
-    companion object {
-        private const val TAG = "MainActivity"
-        private const val NOTIFICATION_REQUEST_CODE = 1234
-    }
+  companion object {
+    private const val TAG = "MainActivity"
+    private const val NOTIFICATION_REQUEST_CODE = 1234
+  }
 
-    override fun onCreate(savedInstanceState: Bundle?) {
-        super.onCreate(savedInstanceState)
-        // [START handle_data_extras]
-        intent.extras?.let {
-            for (key in it.keySet()) {
-                val value = intent.extras?.get(key)
-                Log.d(TAG, "Key: $key Value: $value")
-            }
-        }
-        // [END handle_data_extras]
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    // [START handle_data_extras]
+    intent.extras?.let {
+      for (key in it.keySet()) {
+        val value = intent.extras?.get(key)
+        Log.d(TAG, "Key: $key Value: $value")
+      }
     }
+    // [END handle_data_extras]
+  }
 
-    fun runtimeEnableAutoInit() {
-        // [START fcm_runtime_enable_auto_init]
-        Firebase.messaging.isAutoInitEnabled = true
-        // [END fcm_runtime_enable_auto_init]
-    }
+  fun runtimeEnableAutoInit() {
+    // [START fcm_runtime_enable_auto_init]
+    Firebase.messaging.isAutoInitEnabled = true
+    // [END fcm_runtime_enable_auto_init]
+  }
 
-    fun deviceGroupUpstream() {
-        // [START fcm_device_group_upstream]
-        val to = "a_unique_key" // the notification key
-        val msgId = AtomicInteger()
-        Firebase.messaging.send(
-            remoteMessage(to) {
-                setMessageId(msgId.get().toString())
-                addData("hello", "world")
-            },
-        )
-        // [END fcm_device_group_upstream]
-    }
+  fun deviceGroupUpstream() {
+    // [START fcm_device_group_upstream]
+    val to = "a_unique_key" // the notification key
+    val msgId = AtomicInteger()
+    Firebase.messaging.send(
+      remoteMessage(to) {
+        setMessageId(msgId.get().toString())
+        addData("hello", "world")
+      },
+    )
+    // [END fcm_device_group_upstream]
+  }
 
-    fun sendUpstream() {
-        val SENDER_ID = "YOUR_SENDER_ID"
-        val messageId = 0 // Increment for each
-        // [START fcm_send_upstream]
-        val fm = Firebase.messaging
-        fm.send(
-            remoteMessage("$SENDER_ID@fcm.googleapis.com") {
-                setMessageId(messageId.toString())
-                addData("my_message", "Hello World")
-                addData("my_action", "SAY_HELLO")
-            },
-        )
-        // [END fcm_send_upstream]
-    }
+  fun sendUpstream() {
+    val SENDER_ID = "YOUR_SENDER_ID"
+    val messageId = 0 // Increment for each
+    // [START fcm_send_upstream]
+    val fm = Firebase.messaging
+    fm.send(
+      remoteMessage("$SENDER_ID@fcm.googleapis.com") {
+        setMessageId(messageId.toString())
+        addData("my_message", "Hello World")
+        addData("my_action", "SAY_HELLO")
+      },
+    )
+    // [END fcm_send_upstream]
+  }
 
-    fun subscribeTopics() {
-        // [START subscribe_topics]
-        Firebase.messaging.subscribeToTopic("weather")
-            .addOnCompleteListener { task ->
-                var msg = "Subscribed"
-                if (!task.isSuccessful) {
-                    msg = "Subscribe failed"
-                }
-                Log.d(TAG, msg)
-                Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
-            }
-        // [END subscribe_topics]
-    }
+  fun subscribeTopics() {
+    // [START subscribe_topics]
+    Firebase.messaging.subscribeToTopic("weather")
+      .addOnCompleteListener { task ->
+        var msg = "Subscribed"
+        if (!task.isSuccessful) {
+          msg = "Subscribe failed"
+        }
+        Log.d(TAG, msg)
+        Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
+      }
+    // [END subscribe_topics]
+  }
 
-    fun logRegToken() {
-        // [START log_reg_token]
-        Firebase.messaging.getToken().addOnCompleteListener { task ->
-            if (!task.isSuccessful) {
-                Log.w(TAG, "Fetching FCM registration token failed", task.exception)
-                return@addOnCompleteListener
-            }
+  fun logRegToken() {
+    // [START log_reg_token]
+    Firebase.messaging.getToken().addOnCompleteListener { task ->
+      if (!task.isSuccessful) {
+        Log.w(TAG, "Fetching FCM registration token failed", task.exception)
+        return@addOnCompleteListener
+      }
 
-            // Get new FCM registration token
-            val token = task.result
+      // Get new FCM registration token
+      val token = task.result
 
-            // Log and toast
-            val msg = "FCM Registration token: $token"
-            Log.d(TAG, msg)
-            Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
-        }
-        // [END log_reg_token]
+      // Log and toast
+      val msg = "FCM Registration token: $token"
+      Log.d(TAG, msg)
+      Toast.makeText(baseContext, msg, Toast.LENGTH_SHORT).show()
     }
+    // [END log_reg_token]
+  }
 
-    // [START ask_post_notifications]
-    // Declare the launcher at the top of your Activity/Fragment:
-    private val requestPermissionLauncher = registerForActivityResult(
-        ActivityResultContracts.RequestPermission(),
-    ) { isGranted: Boolean ->
-        if (isGranted) {
-            // FCM SDK (and your app) can post notifications.
-        } else {
-            // TODO: Inform user that that your app will not show notifications.
-        }
+  // [START ask_post_notifications]
+  // Declare the launcher at the top of your Activity/Fragment:
+  private val requestPermissionLauncher = registerForActivityResult(
+    ActivityResultContracts.RequestPermission(),
+  ) { isGranted: Boolean ->
+    if (isGranted) {
+      // FCM SDK (and your app) can post notifications.
+    } else {
+      // TODO: Inform user that that your app will not show notifications.
     }
+  }
 
-    private fun askNotificationPermission() {
-        // This is only necessary for API level >= 33 (TIRAMISU)
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
-            if (ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) ==
-                PackageManager.PERMISSION_GRANTED
-            ) {
-                // FCM SDK (and your app) can post notifications.
-            } else if (shouldShowRequestPermissionRationale(Manifest.permission.POST_NOTIFICATIONS)) {
-                // TODO: display an educational UI explaining to the user the features that will be enabled
-                //       by them granting the POST_NOTIFICATION permission. This UI should provide the user
-                //       "OK" and "No thanks" buttons. If the user selects "OK," directly request the permission.
-                //       If the user selects "No thanks," allow the user to continue without notifications.
-            } else {
-                // Directly ask for the permission
-                requestPermissionLauncher.launch(Manifest.permission.POST_NOTIFICATIONS)
-            }
-        }
+  private fun askNotificationPermission() {
+    // This is only necessary for API level >= 33 (TIRAMISU)
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+      if (ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) ==
+        PackageManager.PERMISSION_GRANTED
+      ) {
+        // FCM SDK (and your app) can post notifications.
+      } else if (shouldShowRequestPermissionRationale(Manifest.permission.POST_NOTIFICATIONS)) {
+        // TODO: display an educational UI explaining to the user the features that will be enabled
+        //       by them granting the POST_NOTIFICATION permission. This UI should provide the user
+        //       "OK" and "No thanks" buttons. If the user selects "OK," directly request the permission.
+        //       If the user selects "No thanks," allow the user to continue without notifications.
+      } else {
+        // Directly ask for the permission
+        requestPermissionLauncher.launch(Manifest.permission.POST_NOTIFICATIONS)
+      }
     }
-    // [END ask_post_notifications]
-
-    // [START get_store_token]
-    private suspend fun getAndStoreRegToken(): String {
-        val token = Firebase.messaging.token.await()
-        // Add token and timestamp to Firestore for this user
-        val deviceToken = hashMapOf(
-            "token" to token,
-            "timestamp" to FieldValue.serverTimestamp(),
-        )
-
-        // Get user ID from Firebase Auth or your own server
-        Firebase.firestore.collection("fcmTokens").document("myuserid")
-            .set(deviceToken).await()
-        return token
+  }
+  // [END ask_post_notifications]
+
+  // [START get_store_token]
+  private suspend fun getAndStoreRegToken(): String {
+    val token = Firebase.messaging.token.await()
+    // Add token and timestamp to Firestore for this user
+    val deviceToken = hashMapOf(
+      "token" to token,
+      "timestamp" to FieldValue.serverTimestamp(),
+    )
+
+    // Get user ID from Firebase Auth or your own server
+    Firebase.firestore.collection("fcmTokens").document("myuserid")
+      .set(deviceToken).await()
+    return token
+  }
+  // [END get_store_token]
+
+    private fun registerFid() {
+        // [START register_fid]
+        // Trigger manual registration if auto-initialization is turned off.
+        // Consider calling this every time the app starts to guarantee sync status.
+        FirebaseMessaging.getInstance().register()
+            .addOnCompleteListener(this) { task ->
+                if (!task.isSuccessful()) {
+                    Log.w(TAG, "Failed to register with Firebase Cloud Messaging", task.exception)
+                }
+                // Success! The Firebase Installation ID can be used to target messages to this app
+                // instance and will be delivered asynchronously to your onRegistered() callback.
+            }
+        // [END register_fid]
     }
-    // [END get_store_token]
 }

messaging/app/src/main/java/com/google/firebase/example/messaging/kotlin/MyFirebaseMessagingService.kt

@@ -133,4 +133,23 @@ class MyFirebaseMessagingService : FirebaseMessagingService() {
             return Result.success()
         }
     }
+
+    // [START on_fid_registered]
+    /**
+     * There are three scenarios when `onRegistered` is called:
+     * 1) Every time a manual `register()` call finishes successfully
+     * 2) Whenever the FID is changed and the app is re-registered with FCM via the new FID.
+     * 3) Automatically on the first app startup or routine sync when auto-initialization is enabled.
+     * Under #2, there are three scenarios when the existing FID is changed:
+     * A) App is restored to a new device
+     * B) User uninstalls/reinstalls the app
+     * C) User clears app data
+     */
+    override fun onRegistered(installationId: String) {
+        Log.d(TAG, "Registered installation ID: $installationId")
+
+        // Send the Firebase Installation ID to your app server.
+        sendRegistrationToServer(installationId)
+    }
+    // [END on_fid_registered]
 }