So I've made an Android video-calling app that tries to be available in the background so that the user may receive calls when the screen is off. I've noticed however that the app would be paused when the device went to sleep.
The solution I've found that worked was to rewrite everything to a service and then request a wakelock so the service wouldn't be paused during sleep.
Surely, since there are so many of these types of apps, there is a more elegant way to do this? A periodic check wouldn't work since you would want to take the call in real-time.
It depends on the Android version, for version older than 6 a partial wakelock is enough to keep the device awake, for Android 6 you also need a foreground service, that's a Service that calls startForeground() and shows a notification, but to keep the device awake has a big impact in battery usage.
You do not necessarily need to transfer all the code to the Service due it is the whole application that stays awake.
A more elegant solution to replace all this would probably be to use Push Notifications, it is what most messaging applications use. Firebase has Push Notifications.
Related
In my app I want to show notification on exact time when the app is working in background or even it is closed. I used AlarmManager and service with BroadcastReceiver to show notification. The latest versions of android doesn't allow to run service in background after app closed and foreground service is consuming battery, slowing down the device etc.. I wonder if I could use something else can work even app is closed and show the notifications. I've heard of WorkManager and JobScheduler for that kind of operations but can they do the work even if app is closed?
Foreground services is not consuming more battery and not slowing down device, just notification is shown.
And the answer is basically it is not possible to make continuous background service on new android API's. You only can schedule tasks with tools like WorkManager, JobScheduler and so on.
These days I think WorkManager is the answer because Android team is focused on it this year.
Also even continuous foreground services gets killed after some time.... To avoid that 2 things has to be done:
Native battery optimization for app should be disabled.
Phone manufacturer (another battery optimization) has to be also disabled for specific app.....
I know it is worst user experience, and they throwing away half smart things that phone can do, but life is life :)
I believe you all are already familiar with "background service limitations" imposed on Android 8.0 and up (https://developer.android.com/about/versions/oreo/background.html#services).
I'm having a very particular problem right now. My application is meant for a very specific use case. App checks for certain data on the server every minute and in case of some wrong value, user is being alerted immediately. Obviously so far application was running in a form of background service and my customers never cared about (obvious) battery consumption coming from complex calculations that are being performed every minute.
Now, whole idea is that app needs to stay alive, working and in background (even with permanent notification, i don't have anything to hide) regardless of anything! If phone is in a deepest possible sleep state - service needs to keep running. If there's 2% battery left - service needs to keep running. So far, i managed to achieve that using alarms and "guardian services" which prevented any way of stopping the background service while app is installed. But now, with Android "0" - what's the way to go? Is there a JobScheduler that will guarantee execution at given rate (every minute) regardless of anything?
How SMS / Phone, WhatsApp and similar apps achieve that "awake no matter what" state?
That's what Google tells us.
A process is not forever.
If you feel you need your foreground service to stay alive
permanently, then this is an indicator that a foreground service is
not the right answer.
Effective foreground services on Android
I think you could use repetitive tasks with WorkManager or change the architecture and use FCM. In any case, Google will not let us work as it did before.
I am developing multiplayer game using Socket.io library. it Works Well.
But, in android 7.0 and above, system automatically suspend all network work when my app is in background. (And I must need to keep alive my socket connection).
I research about it as described here.
but, i can't understand. So, Please provide solution for that.
Unfortunately there's bad news and some good news for you on this.
Bad:
Since android marshmallow and above, there's a concept of a doze mode. If the device stays put for some time (can't confirm the duration for this and not disclosed by google), the device will go into doze mode and will suspend all network activity. There will be short maintenance windows where in you will be able to do syncs and stuff. Small workaround, do not target 23+ apis, i say small because i have observed this to not work on some phones. Another way to potentially bypass this would be to whitelist your app from battery restrictions but according to google guidelines, i don't think your app will qualify for that.
Worse news is that start from API 26, background services will also get suspended completely when app is totally backgrounded and has no visible component (a notification or a foreground service etc...). So oreo will be worse.
Good:
You might not really want to constantly keep the socket open. Instead opt for bursts of syncs. I personally have a job run every 30 - 60 mins or so to try and sync up.
You can leverage the JobScheduler apis and it will automatically handle the doze modes and stuff and you can make them run periodically when there is internet connection. While the job is running, you can connect to your server, do your thing and shut the socket. This is what google wants and is pushing all devs towards.
UPDATE 19-Apr-2021
WorkManager is the new and the best way to deal with doze mode and background limit restrictions.
Another alternative would be to have a foreground service with an active notification displayed which would constantly be connected via your socket. This will be visible to the user and it will not only annoy them that you are constantly using their data, it can also be bad for the battery. Alternative to this again is using the job scheduler to schedule and run a foreground service periodically so as to be transparent while also syncing your data every once in a while. The latter approach is what WhatsApp does, they have a job running which syncs all incoming messages with a foreground service once in a while.
In Short:
You will not be able to keep it alive always. You can try doing it in bursts using one of the methods that i described and know currently (maybe there are other alternatives that i don't know, i have tested these and they work) You will have to compromise, sorry.
Currently i reading in official google doc news about Android 7.0
I can not understand a few things.
They wrote Doze improve battery life by turn off network and CPU when user block the screen.
But how this works ?
1.I have Marshmallow in my device, and when my phone is blocked, i still get notifications from app with network (e.g. Messenger).
2.Second thing they wrote Nougat have improved this more by again CPU and network. So what is exacly differet ?
I have Marshmallow in my device, and when my phone is blocked, i still get notifications from app with network (e.g. Messenger).
SMS does not usually go over the Internet, assuming that is what you mean by "Messenger" (many apps use that name). Plus, high-priority FCM push messages work despite Doze mode.
Second thing they wrote Nougat have improved this more by again CPU and network. So what is exacly differet ?
There is a "Doze on the go mode" that kicks in even if the device is moving. This is covered in the documentation and in the documentation.
Push Notifications will still get through, but most services will stop running after a while if you leave your phone sitting on a table with the screen off.
For example Spotify still keeps running smoothly because it has a foreground notification. The battery savings come from when the OS can shut down most systems such as internet and geolocation as well as avoiding running other services for increasingly longer periods of time,for example reaching stretches of hours by the end of a typical user's sleep at night.
Now they're mainly doing what they were saying for a long time: background services have no guarantees of how long they will run. The biggest unintended consequence is that sometimes when they wake up there's no internet or geolocation is not available. And the time they run is less predictable.
There's still ways to wake up and perform tasks with perfect predictability using exact alarms or push notifications, depending on where the event is generated. But for most cases the recommended solution is using job schedulers.
I've been looking through many questions about services, but I couldn't find one that suited me.
I need a service that both starts on BOOT_COMPLETED (not bound to an Activity) and runs ALL the time (therefore I can't user AlarmReceiver). I know it might drain my battery but so far I don't care. It is just for research purposes.
I have a service that monitors sensor's data. What I managed to do so far was: either start the service as a regular Activity, but it runs only for +-20s and it is stopped (I think the SO cuts it down to release its memory); or start a service that runs in foreground. It worked to keep the process running, however the class that actually runs the service somehow was not started, besides an annoying notification which is required.
The code I refered as the one that runs the service in foreground was taken from here:
Implement startForeground method in Android
I mean, how does an app like WhatsApp run constantly? Is it running in foreground? Because looking at Settings it seems the service is very stable, and it does not show any permanent notification, since it is not possible for a foreground service run without one.
( How to startForeground() without showing notification? )
Any advice?
You can use a WakeLock. But please remember, with great power comes great responsibility (to release them again and not over-use them).
But for now, just acquire a hefty WakeLock and only release it until you are done. This should keep your device's screen and CPU awake and allow you to do whatever it is you want to do.