Develop Reference

Loosing network android 6 and above if app run in backgroud

I am running service background to execute some tasks with some interval using AlaramManager (setExactAndAllowWhileIdle). If its connected the power charger its running. But if its unplugged device power after some i am loosing the network to my application.
Alaram is waking up the service even device is idle.But my app don't have network.
As per https://developer.android.com/training/monitoring-device-state/doze-standby.html# its restricting the network when phone is idle.I tested the same with applying phone idle ($ adb shell dumpsys battery unplug)
But is there any possible to get network access to my application even phone is idle mode.
Application is not of play store. Its really appropriated for suggestion.

I've used PowerManager.isDeviceIdleMode() in your running service to detect whether you're in Doze and if so just invoke setAlarmClock() method with 250 millis (for example) and random broadcast just to wake the device up, it'll completely wake up from doze and thus will get network access as usual. THe down side is that you lose the battery saving that comes with doze.. :D Please mark this as useful should it actually be usefull in your case.
Once your service (set up with setExactAndAllowWhileIdle()) you can go :
private boolean isDeviceInDozeMode() {
PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
return pm.isDeviceIdleMode();
So now you know that you're in DOZE or not.
Then you can just set up AlarmClock and set it with setAlarmClock(AlarmClockInfo a, PendingIntent p)
And you're out of Doze with normal network access.
NOTE: Please remember that using setExactAndAllowWhileIdle doesn't mean that your alarm will go off at specified time, it will go off sooner than normal set() method, but not exact (as the method name would suggest). Generally my way isn't perfect in terms of scheduling, but it does exit DOZE programmatically once it's detected on device.
Let me know should you need more update.

I tried many options but none of them works, But finally this works to me.It might help for others.
we can always ask the user to let your app ignore battery optimization functionality using
PowerManager powerManager = (PowerManager)
getSystemService(Context.POWER_SERVICE);
Intent intent=new Intent();
intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
if (powerManager.isIgnoringBatteryOptimizations(getPackageName())) {
intent.setAction(Settings.ACTION_IGNORE_BATTERY_OPTIMIZATION_SETTINGS);
}
else {
intent.setAction(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS);
intent.setData(Uri.parse("package:" + getPackageName()));
startActivity(intent);
}
and in the manifest
<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"></uses-permission>
But remember this might make your app not approved by Google Play
https://developer.android.com/training/monitoring-device-state/doze-standby.html#whitelisting-cases

How to keep Android awake in background when screen is off

I runs web server in my rooted Android Tablet. I setup it for web development. I created a home network by this Android server. but when the screen of the tab turns off, the server also stop working & again start working when i turn on the screen. but its not possible to turn on the screen for long time. I can be harmful for my tablet. Is there any way to keep awake my tablet when the screen is turn off so that my server can work properly in Background.
please help

You can run a service in the background and acquire lock like this :
PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
WakeLock wakeLock = powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK,
"MyWakelockTag");
wakeLock.acquire();
and return onStartCommand START_STICKY. To release the wake lock, call wakelock.release().
Do not forget to put the permission in the manifest file :
<uses-permission android:name="android.permission.WAKE_LOCK" />
Or you can use this app to prevent phone from sleeping :
https://play.google.com/store/apps/details?id=nl.syntaxa.caffeine

How to avoid user turn off the screen which result in the wifi turned off during downloading

In my application, I use AsyncTask to download large files (300M+). I noticed that when the user turns off their screen (locks their device), the wifi will disconnect and the download will hang.
I wonder if it is possible to avoid this?

You required to implement WakeLock in your application. Wakelock will wake up the CPU incase of screen is off and performs the operations in normal ways.
Write down following code before starting the AsyncTask,
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK|PowerManager.ACQUIRE_CAUSES_WAKEUP, "bbbb");
wl.acquire();
You need to write wl.release(); on PostExecution() method. And you need to define permission in AndroidManifest.xml as follows,
<uses-permission android:name="android.permission.WAKE_LOCK" />

The common practice in this case is to take a WakeLock to keep the CPU awake, and take a WifiLock to keep the wifi connected, so that your app keeps running even if the screen is turned off.
Don't forget to release the locks when you're done!

How to keep awake my android device

Right now my app has to stream music. I'm using a web server and everything works if the phone is awake or is plugged in to a power source.
But I really need to continue streaming until the phone go to sleep. I'm using PowerManager PowerManager.WakeLock in order to keep the phone awake.
This is part of my code:
pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
wl.setReferenceCounted(true);
After that I have the wl.acquire(); and the release. I have a handler that does the release 5 minutes after the songs stop streaming.
int timeToWait = 300000;
turnOffDevice.sendEmptyMessageDelayed(0, timeToWait);
But it works for a short period of time then the song starts jumping and most of time the songs stop.

Hi I've already fix my problem, the problem was in the wifi, it was sleeping after some time so I added a wifilock and in the constructor of the class in I'm using WIFI_MODE_FULL_HIGH_PERF this flag avoid the device turn off the wifi
wifilock = manager.createWifiLock(3,TAG);// WIFI_MODE_FULL_HIGH_PERF
The only problem is this flag is only available since API 12, but for now is not a big deal into my project. If you want more information in this linkWIFI_MODE_FULL_HIGH_PERF

Unable to Keep Screen from Sleeping in Android 4.2

I have a simple battery test app I wrote for Android and have used for several versions now successfully. It works fine in Android 4.1 The app simply launches the chrome browser to a different web site, logs the time to a database, waits 60 seconds and does it all over again.
Now, in Android 4.2, the screen turns off and system goes to sleep despite the fact that I have a wakelock and have set screen timeout to never using settings. What's most annoying is it turns off at an indeterminate time, not a fixed time after starting the test. Any idea what I need to do?
Here's the wakelock code I call in the service that launches the browser over and over again.
super.onCreate();
// Wakelock
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Tag");
wl.acquire();
I also put this in the layout file
android:keepScreenOn="true"
However, the app's screen itself isn't visible throughout the test as Chrome is always the foreground window and the browser launcher is a service and the wakelock is in the service.
Any idea how to keep the screen from timing out? Nothing seems to work.

Just add following line to your XML file......
android:keepScreenOn="true"
:)

I would guess that Android is killing your service and causing your wakelock to be released. Try making your service run in the foreground (with startForeground()) and see if that helps.