Compatible with Android 8

Author: jsdario

android/app/build.gradle

@@ -94,13 +94,13 @@ def enableSeparateBuildPerCPUArchitecture = false
 def enableProguardInReleaseBuilds = false
 
 android {
-    compileSdkVersion 28
-    buildToolsVersion "28.0.0"
+    compileSdkVersion rootProject.ext.compileSdkVersion
+    buildToolsVersion rootProject.ext.buildToolsVersion
 
     defaultConfig {
         applicationId "com.androidwidgetpoc"
-        minSdkVersion 16
-        targetSdkVersion 28
+        minSdkVersion rootProject.ext.minSdkVersion
+        targetSdkVersion rootProject.ext.targetSdkVersion
         versionCode 1
         versionName "1.0"
         ndk {
@@ -138,8 +138,8 @@ android {
 
 dependencies {
     implementation fileTree(dir: "libs", include: ["*.jar"])
-    implementation "com.android.support:appcompat-v7:23.0.1"
-    implementation 'com.android.support:support-v4:23.2.0' // v4
+    implementation "com.android.support:appcompat-v7:${rootProject.ext.supportLibVersion}"
+    implementation "com.android.support:support-v4:${rootProject.ext.supportLibVersion}" // v4
     implementation "com.facebook.react:react-native:+"  // From node_modules
 }
 

android/app/src/main/java/com/androidwidgetpoc/BackgroundTask.java

@@ -18,52 +18,39 @@
 public class BackgroundTask extends HeadlessJsTaskService {
 
     private final int NOTIFICATION_ID = 12345678;
-    private final String CHANNEL_ID = "channel_id";
+    private final String CHANNEL_ID = "headless_task_channel";
 
     @Override
     protected @Nullable
     HeadlessJsTaskConfig getTaskConfig(Intent intent) {
+        startForeground(NOTIFICATION_ID, getNotification());
+
+        Bundle extras = intent.getExtras();
+        return new HeadlessJsTaskConfig(
+                "WidgetTask",
+                extras != null ? Arguments.fromBundle(extras) : null,
+                10000);
+    }
+
+    private Notification getNotification() {
         NotificationManager notificationManager = getSystemService(NotificationManager.class);
-        /*
-        * This is run inside onStartCommand
-        * */
+
         // Android O requires a Notification Channel.
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
             CharSequence name = "channel name";
             // Create the channel for the notification
             NotificationChannel mChannel =
                     new NotificationChannel(CHANNEL_ID, name, NotificationManager.IMPORTANCE_DEFAULT);
 
-            // Set the Notification Channel for the Notification Manager.
             notificationManager.createNotificationChannel(mChannel);
-            // notificationManager.startServiceInForeground(intent, NOTIFICATION_ID, getNotification());
-            startForegroundService(NOTIFICATION_ID, getNotification());
-        } else {
-            startForeground(NOTIFICATION_ID, getNotification());
         }
 
-        Bundle extras = intent.getExtras();
-        return new HeadlessJsTaskConfig(
-                "WidgetTask",
-                extras != null ? Arguments.fromBundle(extras) : null,
-                10000);
-    }
-
-    private Notification getNotification() {
-        NotificationCompat.Builder builder = new NotificationCompat.Builder(this)
-                .setContentText("Some text")
-                .setContentTitle("Some title")
-                .setOngoing(true)
-                .setPriority(Notification.PRIORITY_HIGH)
+        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, CHANNEL_ID)
+                .setContentText("Your JS code is going to be run in background")
+                .setContentTitle("Launching HeadlessJsTaskService")
                 .setSmallIcon(R.mipmap.ic_launcher)
-                .setTicker("Some title")
                 .setWhen(System.currentTimeMillis());
 
-        // Set the Channel ID for Android O.
-        // if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-        //    builder.setChannelId(CHANNEL_ID); // Channel ID
-        // }
-
         return builder.build();
     }
 }

android/app/src/main/java/com/androidwidgetpoc/BackgroundTaskBridge.java

@@ -96,7 +96,7 @@ private void updateView(RemoteViews widgetView, ReadableMap charm, Integer layou
     }
 
     private void registerTask(String action, ReadableMap charm, RemoteViews widgetView, Integer button) {
-        Intent intent = new Intent();
+        Intent intent = new Intent(getReactApplicationContext(), WidgetProvider.class);
         intent.putExtra("id", charm.getString("id"));
         intent.setAction(action);
         PendingIntent pendingIntent = PendingIntent.getBroadcast(this.getReactApplicationContext(), 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);

android/app/src/main/java/com/androidwidgetpoc/WidgetProvider.java

@@ -3,6 +3,7 @@
 import android.appwidget.AppWidgetProvider;
 import android.content.Context;
 import android.content.Intent;
+import android.os.Build;
 import android.util.Log;
 
 import com.facebook.react.HeadlessJsTaskService;
@@ -17,9 +18,8 @@ public class WidgetProvider extends AppWidgetProvider {
 
     @Override
     public void onEnabled(Context context) {
-        Log.d("WIDGET_PROVIDER", "En onEnabled");
-        Intent serviceIntent = new Intent(context, BackgroundTask.class);
-        context.startService(serviceIntent);
+        Intent intent = new Intent(context, BackgroundTask.class);
+        startServiceAfterSdkVersion(context, intent);
         HeadlessJsTaskService.acquireWakeLockNow(context);
     }
 
@@ -36,6 +36,14 @@ public void onReceive(final Context context, final Intent incomingIntent) {
         * */
         Intent serviceIntent = new Intent(context, BackgroundTask.class);
         serviceIntent.putExtras(incomingIntent);
-        context.startService(serviceIntent);
+        startServiceAfterSdkVersion(context, serviceIntent);
+    }
+
+    public void startServiceAfterSdkVersion (Context context, Intent intent) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            context.startForegroundService(intent);
+        } else {
+            context.startService(intent);
+        }
     }
 }

android/build.gradle

@@ -21,5 +21,16 @@ allprojects {
             // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
             url "$rootDir/../node_modules/react-native/android"
         }
+        google()
     }
 }
+
+
+ext {
+    compileSdkVersion = 27
+    minSdkVersion = 16
+    targetSdkVersion = 27
+    buildToolsVersion = "27.0.3"
+    supportLibVersion = "27.1.0"
+    googlePlayServicesVersion = "11.8.0"
+}

jsconfig.json

@@ -24,11 +24,14 @@ type TaskInfo = {
 }
 export default function widgetTask (taskData: TaskInfo) {
   synchronizeWidget()
-  triggerCharm(taskData.id)
+  if (taskData && taskData.id) {
+    triggerCharm(taskData.id)
+  }
 
   return new Promise(resolve => {
     setTimeout(() => {
         ToastAndroid.show(`FINISHING 🚬 ...`, ToastAndroid.SHORT);
+        synchronizeWidget()
         resolve()
     }, 8000) 
   })