Develop Reference

Android: Stop Foreground Service causing Application crash

Prerequisites:
As a part of the requirement for my application, I need to make sure that the application won't be closed (killed) by the Android system while in background. For this purpose I implemented Foreground service, even though I don't do any actual process in background, just maintaining the state of the application. Everything works just fine, except one thing which is not fully clear to me how to fix.
The issue:
Sometimes (only once, for now), I receive this exception:
android.app.RemoteServiceException: Context.startForegroundService() did not then call Service.startForeground():
This exception is thrown when I'm trying to stop the foreground service while it wasn't actually started.
So, my question is - is there is a way to stop foreground service properly, making sure that it is not running before actually stopping it?
What I found at the moment is that I can have static instance for my service and compare to null before stopping service, or get the list of all services currently running. But all these look like some "hack" workarounds.
Here some code:
MyForegroundService:
public class ForegroundService extends Service {
public static final int NOTIFICATION_ID = 1;
public static final String CHANNEL_ID = "SessionForegroundServiceChannel";
public static final String ACTION_FOREGROUND_START = "ACTION_FOREGROUND_START";
public static final String ACTION_FOREGROUND_STOP = "ACTION_FOREGROUND_STOP";
public static void startForegroundService(Context context) {
Intent intent = new Intent(context, ForegroundService.class);
intent.setAction(ForegroundService.ACTION_FOREGROUND_START);
ContextCompat.startForegroundService(context, intent);
}
public static void stopForegroundService(Context context) {
Intent intent = new Intent(context, ForegroundService.class);
intent.setAction(ForegroundService.ACTION_FOREGROUND_STOP);
ContextCompat.startForegroundService(context, intent);
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
if (ACTION_FOREGROUND_START.equals(intent.getAction())) {
createNotificationChannel();
Intent stopForegroundIntent = new Intent(this, ForegroundServiceBroadcastReceiver.class);
PendingIntent pendingLogoutIntent = PendingIntent.getBroadcast(this,
0, stopForegroundIntent, PendingIntent.FLAG_UPDATE_CURRENT);
Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
.setContentTitle(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O
? null
: getString(R.string.app_short_name))
.setContentText(getString(R.string.foreground_description))
.setColor(getResources().getColor(R.color.color))
.setSmallIcon(R.drawable.ic_notification)
.addAction(R.drawable.ic_logout, getString(R.string.logout), pendingLogoutIntent)
.build();
startForeground(NOTIFICATION_ID, notification);
} else if (ACTION_FOREGROUND_STOP.equals(intent.getAction())) {
stopForeground(true);
stopSelf();
}
return START_STICKY;
}
private void createNotificationChannel() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationChannel serviceChannel = new NotificationChannel(
CHANNEL_ID,
getString(R.string.app_name),
NotificationManager.IMPORTANCE_LOW
);
NotificationManager manager = getSystemService(NotificationManager.class);
manager.createNotificationChannel(serviceChannel);
}
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
}
<service
android:name=".ui.ForegroundService"
android:exported="false"
android:stopWithTask="true"/>
I also have BroadcastReceiver and EventBus to listen to some events and stop foreground depending on those events.
Can you please help me, guys?

Let me add more details to what #Pawel commented:
You get this exception if you don't call Service.startForeground within 3 seconds of calling Context.startForegroundService that's all there's to it.
Here is how the complete solution will look like:
When it comes to the case when you need to stop a foreground service you need to do the following (pseudo code):
if (action == START_FOREGROUND) {
...
startForeground(NOTIFICATION_ID, notification);
} else if (action == STOP_FOREGROUND) {
startForeground(NOTIFICATION_ID, closeNotification); //in case it wasn't started before
stopForeground(true);
stopSelf();
}
Even though it is not obvious, and any documentation don't directly say that when you need to stop foreground you need to start foreground before stopping it (if it wasn't started).
Thanks #Pawel for the hint.

Android, Display alertDialog instead of notification when app is open

I followed this developer tutorial, and have Geofencing working within my app, as expected.
A notification is sent when a Geofence Transition occurs, from within an IntentService:
#Override
protected void onHandleIntent(Intent intent) {
GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
...
sendNotification(geofenceTransitionDetails);
}
private void sendNotification(String notificationDetails) {
// Create an explicit content Intent that starts the main Activity.
Intent notificationIntent = new Intent(getApplicationContext(), MainActivity.class);
// Construct a task stack.
TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
// Add the main Activity to the task stack as the parent.
stackBuilder.addParentStack(MainActivity.class);
// Push the content Intent onto the stack.
stackBuilder.addNextIntent(notificationIntent);
// Get a PendingIntent containing the entire back stack.
PendingIntent notificationPendingIntent =
stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
// Get a notification builder that's compatible with platform versions >= 4
NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
// Define the notification settings.
builder.setSmallIcon(R.mipmap.ic_launcher)
// In a real app, you may want to use a library like Volley
// to decode the Bitmap.
.setLargeIcon(BitmapFactory.decodeResource(getResources(),
R.mipmap.ic_launcher))
.setColor(Color.RED)
.setContentTitle(notificationDetails)
.setContentText("Return to app")
.setContentIntent(notificationPendingIntent);
// Dismiss notification once the user touches it.
builder.setAutoCancel(true);
// Get an instance of the Notification manager
NotificationManager mNotificationManager =
(NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// Issue the notification
mNotificationManager.notify(0, builder.build());
}
This is cookie-cutter from the tutorial. The intent is set-up in the Main activity:
private PendingIntent getGeofencePendingIntent() {
// Reuse the PendingIntent if we already have it.
if (mGeofencePendingIntent != null) {
return mGeofencePendingIntent;
}
Intent intent = new Intent(this, GeofenceTransitionsIntentService.class);
// We use FLAG_UPDATE_CURRENT so that we get the same pending intent back when calling
// addGeofences() and removeGeofences().
return PendingIntent.getService(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
}
How can I add functionality that suppresses the notifications if the app is open, and instead displays an AlertDialog to the user? Ideally, I'd like to be able to execute different tasks, depending on which view the user is currently in when the Geofence Transition occurs. Can I monitor/intercept the transition from within each view, or somehow globally?
Thanks in advance.

Some of the answers were incomplete, and so here is the complete solution to what I was looking for.
First off, set up MyApplication class, that implements ActivityLifecycleCallbacks:
public class MyApplication extends Application implements Application.ActivityLifecycleCallbacks {
private static boolean isActive;
#Override
public void onCreate() {
super.onCreate();
registerActivityLifecycleCallbacks(this);
}
public static boolean isActivityVisible(){
return isActive;
}
#Override
public void onActivityResumed(Activity activity) {
isActive = true;
}
#Override
public void onActivityPaused(Activity activity) {
isActive = false;
}
... no other methods need to be used, but there are more that
... must be included for the ActivityLifecycleCallbacks
}
Be sure to name this in your manifest (only name line was added, rest is default):
<application
android:name=".MyApplication"
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme"
android:hardwareAccelerated="true">
What was done above is used to track the lifecycle of your app. You can use this to check if your app is currently in the foreground or not.
Next is to set up a BroadcastReceiver, wherever you would like code to run (in the event that the app is open when the trigger occurs). In this case, it is in my MainActivity:
protected BroadcastReceiver mNotificationReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
... Do whatever you want here
Toast.makeText(...).show();
}
};
Register the receiver in your onCreate of the same activity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
LocalBroadcastManager.getInstance(this).registerReceiver(mNotificationReceiver, new IntentFilter("some_custom_id"));
}
And don't forget to unregister it:
#Override
protected void onDestroy() {
LocalBroadcastManager.getInstance(this).unregisterReceiver(mNotificationReceiver);
super.onDestroy();
}
When a broadcast is received, the code within the receiver is executed.
Now, to check if the app is in the foreground, and send a broadcast if it is. Inside of the IntentService:
#Override
protected void onHandleIntent(Intent intent) {
GeofencingEvent geofencingEvent = GeofencingEvent.fromIntent(intent);
if (geofencingEvent.hasError()) {
String errorMessage = getErrorString(this,
geofencingEvent.getErrorCode());
return;
}
int geofenceTransition = geofencingEvent.getGeofenceTransition();
// Test that the reported transition was of interest.
if (geofenceTransition == Geofence.GEOFENCE_TRANSITION_ENTER ||
geofenceTransition == Geofence.GEOFENCE_TRANSITION_EXIT) {
...
if(MyApplication.isActivityVisible()){
Intent intnt = new Intent("some_custom_id");
intnt.putExtra("message", geofenceTransitionDetails);
LocalBroadcastManager.getInstance(this).sendBroadcast(intnt);
}else{
sendNotification(geofenceTransitionDetails);
}
} else {
// Log the error.
}
}
The important bit is the last nested if-statement:
if(MyApplication.isActivityVisible()){
Intent intnt = new Intent("some_custom_id");
intnt.putExtra("message", geofenceTransitionDetails);
LocalBroadcastManager.getInstance(this).sendBroadcast(intnt);
}else{
sendNotification(geofenceTransitionDetails);
}
Check if the app is in the foreground using MyApplication.isActivityVisible(), as defined above, and then either send the notification, or send a broadcast. Just make sure that your intent code (i.e. "some_custom_id") matches on your sender and receiver.
And that's about it. If the app is in the foreground (specifically the MainActivity), I execute some code. If the app is not in the foreground, I send a notification.

The easiest way would be to use LocalBroadcastManager or some event bus.
So when transition happens you should send local broadcast from IntentService and catch it with some component X in between IntentService and any of your Activity's. Component X must track if any of your Activity's is in foreground and
if yes - pass other local broadcast up (to the foreground Activity),
if not - show notification.
Please note that in Android you cannot track easily if your app is in foreground or not (and if you have more than 1 Activity, you cannot do it properly in my opinion) but you can try.

a) You can notify your service of the activity's lifecycle events.
b) You can keep the current state of your UI in a static field in the activity and check it from the service before showing the notification.

Resume singleTask activity

I am trying to "resume" a single task activity so it appears in the foreground when a user clicks my notification. (Same behavior as if the user tapped on the app icon from the applications menu.)
My notification creates a PendingIntent which broadcasts an action that is received by my broadcast receiver. If the app is in not in the foreground, I try to resume the app. Additionally, I'm trying to pass a message to my onResume function through the intent. However, I'm hitting an error:
Calling startActivity() from outside of an Activity context requires the FLAG_ACTIVITY_NEW_TASK flag. Is this really what you want?
Despite this error, my app is being resumed...don't understand why. However, my extras are not being passed to my onResume function.
So first I create a notification.
public static class MyNotificationCreator {
private static final int MY_NOTIFICATION_ID = 987;
public static void createNotification(Context context) {
Intent openAppIntent = new Intent(context, MyReceiver.class);
openAppIntent.setAction("PleaseOpenApp");
PendingIntent pi = PendingIntent.getBroadcast(context, /*requestCode*/0, openAppIntent, /*flags*/0);
Notification notification = ne Notification.Builder(context)
.setContentTitle("")
.setContentText("Open app")
.setSmallIcon(context.getApplicationInfo().icon)
.setContentIntent(pi)
.build();
NotificationManager notificationManager = (NotificationManager) applicationContext.getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(MY_NOTIFICATION_ID, notification); }
}
Which broadcasts "PleaseOpenApp" for MyReceiver.
public class MyReceiver extends BroadcastReceiver {
#Override
public void onRecieve(Context context, Intent intent) {
if (intent.action() == "PleaseOpenApp" && !MyPlugin.isForeground) {
PackageManager pm = context.getPackageManager();
//Perhaps I'm not supposed to use a "launch" intent?
Intent launchIntent = pm.getLaunchIntentForPackage(context.getPackageName());
//I'm adding the FLAG_ACTIVITY_NEW_TASK, but I'm still hitting an error saying my intent does not have the FLAG_ACTIVITY_NEW_TASK...
launchIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
launchIntent.putExtra("foo", "bar");
context.startActivity(launchActivity);
} else {
//do other stuff
}
}
}
My plugin keeps track of whether or not we're in the foreground. Also, it tries to get "food" after my receiver attempts to start the app.
public class MyPlugin extends CordovaPlugin {
public static boolean isForeground = false;
#Override
public void initialize(CordovaInterface cordova, CordovaWebView webview) {
super.initialize(cordova, webview);
isForeground = true;
}
#Override
public void onResume(boolean multitasking) {
isForeground = true;
String foo = activity.getIntent().getStringExtra("foo");
Log.d("MyPlugin", foo); //foo is null after clicking the notification!
}
#Override
public void onPause(boolean multitasking) {
isForeground = false;
}
#Override
public void onDestroy() {
isForeground = false;
}
}
Note: because I'm using cordova my activity has a singleTask launchMode.
Also, I'm new to Android development so any help about resuming activities not in the foreground vs resuming activities that have been destroyed and info about general concepts / best practices that I'm not understanding would be appreciated!

I don't think your Broadcast/Broadcast Receiver pattern is necessary.
Intents can be used to directly launch an activity, and when you build the Intent, you can add the extras. Then, your activity onResume() can extract them directly.
Here is a sample Intent and PendingIntent construction that can be sent in a notification:
Intent startActivity = new Intent(context, MyActivity.class);
// You can experiment with the FLAGs passed here to see what they change
startActivity.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP | Intent.FLAG_ACTIVITY_NEW_TASK)
.putExtra("Extra1", myExtra1)
.putExtra("Extra2", myExtra2)
// ADDING THIS MAKES SURE THE EXTRAS ATTACH
.setAction("SomeString");
// Then, create the PendingIntent
// You can experiment with the FLAG passed here to see what it changes
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, startActivity, PendingIntent.FLAG_UPDATE_CURRENT);
// Then, create and show the notification
Notification notif = new NotificationCompat.Builder(context)
.setSmallIcon(R.drawable.my_small_icon)
.setContentTitle(myTitle)
.setContentText(myContent)
.setOngoing(isOngoingNotif)
.setAutoCancel(shouldAutoCancel)
.setOnlyAlertOnce(shouldAlertOnce)
.setContentIntent(pendingIntent)
.build();
NotificationManagerCompat manager = NotificationManagerCompat.from(context);
manager.notify(MY_NOTIFICATION_ID, notif);

In your code you are using a "launch Intent" to resume your application. You've added "extras" to the Intent but they will never be seen.
If your app is running, but in the background, and you call startActivity() with a "launch Intent", all this does it bring your task from the background to the foreground. It does not deliver the Intent to the Activity!.
A "launch Intent" does exactly the same thing as when you press the app icon of an app on the HOME screen (if it is already running, but in the background). This just brings the existing task in its current state, from the background to the foreground.
If you want to delivery "extras" to your app, you cannot use a "launch Intent". You must use a regular 'Intent. Depending on your architecture, you could either start a newActivity(which would get the "extras" inonCreate(), or you could start an existingActivity(which would get the "extras" inonNewIntent()`.

stop Activity from displaying - Push notification (Parse)

I have just implemented Parse push notifications into my app. I want to be able to show the push notification, but i don't want the app to open when the user presses the Push notification. Instead, i just want the notification to be dismissed.
i would imagine it would be handled by the ParsePushBroadcastReciever, but i can't find anything online which fits my purpose.
Here is my subclassed ParsepushBroadcastReciever:
public class Receiver extends ParsePushBroadcastReceiver {
#Override
public void onPushOpen(Context context, Intent intent) {
Log.e("Push", "Clicked");
Intent i = new Intent(context, HomeScreen.class);
i.putExtras(intent.getExtras());
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(i);
}
}

In order for you to programatically dismiss a notification you will need to call cancel() using a NotificationManager instance passing in the ID that was passed into notify() on the NotificationManager (since this is what actually pushes the notification into the notification pane). You can't do this using the Parse SDK alone since you will need to take control of the population of notifications yourself.
First you will need to setup a NotificationManager instance then when a notification is ready to be pushed you assign it a value that you can reference later when cancelling like this:
public class MyParsePushBroadcastReceiver extends ParsePushBroadcastReceiver {
NotificationManager mNotificationManager;
int notification_id = 0;
#Override
public void onPushOpen(Context context, Intent intent) {
Log.e("Push", "Clicked");
mNotificationManager.cancel(notification_id)
}
#Override
public void onReceive(Context context, Intent intent) {
mNotificationManager = (NotificationManager)context.getApplicationContext().getSystemService(Context.NOTIFICATION_SERVICE);
super.onReceive(context, intent);
...
}
#Override
protected Notification getNotification(Context context, Intent intent) {
Notification n = super.getNotification(context, intent);
notification_id = intent.getExtras().getInt("NOTIFICATION_TYPE");
mNotificationManager.notify(notification_id, n);
return null;
}
}
So you see by taking control of the NotificationManager (instead of passing it off to the Parse SDK to assign some unknown value) we can know exactly which values to use when calling cancel. I am letting the system build my Notification object (and I get it using super.getNotification()) but you are free to also use a Notification builder to create the notification yourself as well.

android notification in background if app closed?

I am trying to display a notification in the Android notifications bar even if my application is closed.
I've tried searching, but I have had no luck finding help.
An example of this is a news application. Even if the phone screen is off or the news application is closed, it can still send a notification for recent news and have it appear in the notification bar.
How might I go about doing this in my own application?

You have to build a Service that handles your news and shows notifications when it knows that are new news (Service Doc).
The service will run in background even if your application is closed.
You need a BroadcastReciever to run the service in background after the boot phase is completed. (Start service after boot).
The service will build your notifications and send them through the NotificationManager.
EDIT: This article may suit your needs

The selected answer is still correct, but only for devices running Android 7 versions and below.
As of Android 8+, you can no longer have a service running in the background while your app is idle/closed.
So, it now depends on how you set up your notifications from your GCM/FCM server. Ensure to set it to the highest priority. If your app is in the background or just not active and you only send notification data, the system process your notification and send it to the Notification tray.

I used this answer to write a service, and as an exmaple you need to call ShowNotificationIntentService.startActionShow(getApplicationContext()) inside one of your activities:
import android.app.IntentService;
import android.content.Intent;
import android.content.Context;
public class ShowNotificationIntentService extends IntentService {
private static final String ACTION_SHOW_NOTIFICATION = "my.app.service.action.show";
private static final String ACTION_HIDE_NOTIFICATION = "my.app.service.action.hide";
public ShowNotificationIntentService() {
super("ShowNotificationIntentService");
}
public static void startActionShow(Context context) {
Intent intent = new Intent(context, ShowNotificationIntentService.class);
intent.setAction(ACTION_SHOW_NOTIFICATION);
context.startService(intent);
}
public static void startActionHide(Context context) {
Intent intent = new Intent(context, ShowNotificationIntentService.class);
intent.setAction(ACTION_HIDE_NOTIFICATION);
context.startService(intent);
}
#Override
protected void onHandleIntent(Intent intent) {
if (intent != null) {
final String action = intent.getAction();
if (ACTION_SHOW_NOTIFICATION.equals(action)) {
handleActionShow();
} else if (ACTION_HIDE_NOTIFICATION.equals(action)) {
handleActionHide();
}
}
}
private void handleActionShow() {
showStatusBarIcon(ShowNotificationIntentService.this);
}
private void handleActionHide() {
hideStatusBarIcon(ShowNotificationIntentService.this);
}
public static void showStatusBarIcon(Context ctx) {
Context context = ctx;
NotificationCompat.Builder builder = new NotificationCompat.Builder(ctx)
.setContentTitle(ctx.getString(R.string.notification_message))
.setSmallIcon(R.drawable.ic_notification_icon)
.setOngoing(true);
Intent intent = new Intent(context, MainActivity.class);
PendingIntent pIntent = PendingIntent.getActivity(context, STATUS_ICON_REQUEST_CODE, intent, 0);
builder.setContentIntent(pIntent);
NotificationManager mNotificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
Notification notif = builder.build();
notif.flags |= Notification.FLAG_ONGOING_EVENT;
mNotificationManager.notify(STATUS_ICON_REQUEST_CODE, notif);
}
}