Fix Dev-hwang#183.

android/src/main/kotlin/com/pravera/flutter_foreground_task/models/NotificationOptions.kt

@@ -156,6 +156,36 @@ data class NotificationOptions(
             }
         }
 
+        fun notificationContent(context: Context, map: Map<*, *>?) {
+            val prefs = context.getSharedPreferences(
+                PrefsKey.NOTIFICATION_OPTIONS_PREFS, Context.MODE_PRIVATE)
+
+            val id = map?.get(PrefsKey.NOTIFICATION_ID) as? Int ?: 1000
+            val contentTitle = map?.get(PrefsKey.NOTIFICATION_CONTENT_TITLE) as? String ?: ""
+            val contentText = map?.get(PrefsKey.NOTIFICATION_CONTENT_TEXT) as? String ?: ""
+
+            val iconData = map?.get(PrefsKey.ICON_DATA) as? Map<*, *>
+            var iconDataJson: String? = null
+            if (iconData != null) {
+                iconDataJson = JSONObject(iconData).toString()
+            }
+
+            val buttons = map?.get(PrefsKey.BUTTONS) as? List<*>
+            var buttonsJson: String? = null
+            if (buttons != null) {
+                buttonsJson = JSONArray(buttons).toString()
+            }
+
+            with(prefs.edit()) {
+                putInt(PrefsKey.NOTIFICATION_ID, id)
+                putString(PrefsKey.NOTIFICATION_CONTENT_TITLE, contentTitle)
+                putString(PrefsKey.NOTIFICATION_CONTENT_TEXT, contentText)
+                putString(PrefsKey.ICON_DATA, iconDataJson)
+                putString(PrefsKey.BUTTONS, buttonsJson)
+                commit()
+            }
+        }
+
         fun clearData(context: Context) {
             val prefs = context.getSharedPreferences(
                 PrefsKey.NOTIFICATION_OPTIONS_PREFS, Context.MODE_PRIVATE)

android/src/main/kotlin/com/pravera/flutter_foreground_task/service/ForegroundService.kt

@@ -155,6 +155,7 @@ class ForegroundService : Service(), MethodChannel.MethodCallHandler {
 	override fun onMethodCall(call: MethodCall, result: MethodChannel.Result) {
 		when (call.method) {
 			"initialize" -> startForegroundTask()
+			"notification" -> notifyService(call)
 			else -> result.notImplemented()
 		}
 	}
@@ -280,6 +281,45 @@ class ForegroundService : Service(), MethodChannel.MethodCallHandler {
 		isRunningService = false
 	}
 
+	private fun notifyService(call: MethodCall) {
+		val argsMap = call.arguments as? Map<*, *>
+		NotificationOptions.notificationContent(applicationContext, argsMap)
+		notificationOptions = NotificationOptions.getData(applicationContext)
+
+		// channel info
+		val pm = applicationContext.packageManager
+		val channelId = notificationOptions.channelId
+
+		// notification icon
+		val iconData = notificationOptions.iconData
+		val iconBackgroundColor: Int?
+		val iconResId: Int
+		if (iconData != null) {
+			iconBackgroundColor = iconData.backgroundColorRgb?.let(::getRgbColor)
+			iconResId = getIconResIdFromIconData(iconData)
+		} else {
+			iconBackgroundColor = null
+			iconResId = getIconResIdFromAppInfo(pm)
+		}
+
+		// Modify notification
+		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+			val nm = getSystemService(NotificationManager::class.java)
+			val builder = Notification.Builder(this, channelId)
+			builder.setSmallIcon(iconResId)
+			if (iconBackgroundColor != null) {
+				builder.setColor(iconBackgroundColor)
+			}
+			builder.setContentTitle(notificationOptions.contentTitle)
+			builder.setContentText(notificationOptions.contentText)
+			val actions = buildButtonActions().toTypedArray()
+			builder.setActions(*actions)
+			nm.notify(notificationOptions.id, builder.build())
+		}
+
+		isRunningService = true
+	}
+
 	@SuppressLint("WakelockTimeout")
 	private fun acquireLockMode() {
 		if (foregroundTaskOptions.allowWakeLock && (wakeLock == null || wakeLock?.isHeld == false)) {

example/android/build.gradle

@@ -26,6 +26,6 @@ subprojects {
     project.evaluationDependsOn(':app')
 }
 
-task clean(type: Delete) {
+tasks.register("clean", Delete) {
     delete rootProject.buildDir
 }

lib/flutter_foreground_task.dart

@@ -8,6 +8,8 @@ import 'package:flutter_foreground_task/exception/foreground_task_exception.dart
 import 'package:flutter_foreground_task/models/foreground_task_options.dart';
 import 'package:flutter_foreground_task/models/ios_notification_options.dart';
 import 'package:flutter_foreground_task/models/android_notification_options.dart';
+import 'package:flutter_foreground_task/models/notification_button.dart';
+import 'package:flutter_foreground_task/models/notification_icon_data.dart';
 import 'package:flutter_foreground_task/models/notification_permission.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'flutter_foreground_task_platform_interface.dart';
@@ -55,6 +57,7 @@ class FlutterForegroundTask {
   static late IOSNotificationOptions _iosNotificationOptions;
   static late ForegroundTaskOptions _foregroundTaskOptions;
   static bool _initialized = false;
+  static late MethodChannel backgroundChannel;
 
   /// Initialize the [FlutterForegroundTask].
   static void init({
@@ -111,6 +114,27 @@ class FlutterForegroundTask {
   static Future<bool> stopService() =>
       FlutterForegroundTaskPlatform.instance.stopService();
 
+  /// Notifies the foreground service.
+  static Future<bool> notification({
+    required int notificationId,
+    String? notificationTitle,
+    String? notificationText,
+    NotificationIconData? iconData,
+    List<NotificationButton>? buttons,
+  }) async {
+    final options = <String, dynamic>{
+      'notificationId': notificationId,
+      'notificationContentTitle': notificationTitle,
+      'notificationContentText': notificationText,
+      'iconData': iconData?.toJson(),
+      'buttons': buttons?.map((e) => e.toJson()).toList(),
+    };
+
+    // Notifies the foreground task.
+    await backgroundChannel.invokeMethod('notification', options);
+    return true;
+  }
+
   /// Returns whether the foreground service is running.
   static Future<bool> get isRunningService =>
       FlutterForegroundTaskPlatform.instance.isRunningService;
@@ -248,8 +272,8 @@ class FlutterForegroundTask {
   /// It must always be called from a top-level function, otherwise foreground task will not work.
   static void setTaskHandler(TaskHandler handler) {
     // Create a method channel to communicate with the platform.
-    const backgroundChannel =
-        MethodChannel('flutter_foreground_task/background');
+    backgroundChannel =
+        const MethodChannel('flutter_foreground_task/background');
 
     // Binding the framework to the flutter engine.
     WidgetsFlutterBinding.ensureInitialized();