As presented in Droidcon Tel Aviv 2016: http://il.droidcon.com

1. Yonatan Levin
Google Developer Expert
levin.yonatan
parahall

2. 59 Cities > 20M usersRuby, Go, Python, Microservices

3. > 1300 members Largest Android Active Community

4. :)
The story about the shy guy
Doze Mode

9. Doze, the bro :)
No network access
No jobs/ No syncs
No wakelocks
No alarms
No GPS / Wifi Scans

10. Doze Mode on Marshmallow

13. Not shy anymore

14. Doze Mode on Nougat

15. When?
All intervals are configurable by Google/Manufacturer.

16. Statistics on OnePlus 3 (Marshmallow)

17. Statistics on Nexus 6P (Nougat)

18. Doze, sweet, Doze,
Let me go...

19. Charge it...

20. AlarmManager
setAndAllowWhileIdle() or setExactAndAllowWhileIdle().
Could be triggered only once in every 15 minutes
But...

21. No network access

22. GCM/FCM
Use FCM with High priority - but treat it with special care
{
"to" : "...",
"priority" : "high",
"notification" : {
...
},
"data" : {
...
}
}

23. WhiteList
● An app can fire the
ACTION_IGNORE_BATTERY_OPTIMIZATION_SE
TTINGS intent to take the user directly to the
Battery Optimization, where they can add the
app.

24. Note: Google Play policies prohibit apps from
requesting direct exemption from Power
Management features in Android 6.0+ (Doze
and App Standby) unless the core function of
the app is adversely affected.

25. And it’s not all, folks

26. CONNECTIVITY_CHANGES

29. My shiny new app
git clone git@github.com:parahall/final_battle_doze.git

34. public class FinalBattleActivity
public void onClick(View v) {
switch (v.getId()) {
case R.id.kill_button:
StarWarsUtils.makeDecision(
LukeDecision.LUKE_KILL_DARTH_VADER, this);
break;
case R.id.light_side_button:
StarWarsUtils.makeDecision(
LukeDecision.STAY_ON_LIGHT_SIDE, this);
Break;
}
}

35. public class StarWarsUtils {
public static void makeDecision(LukeDecision decision,Context
context) {
Intent nowIntent = new Intent(context, NowIntentService.class);
nowIntent.putExtra(..., decision);
context.startService(nowIntent);
}

36. public class NowIntentService extends IntentService {
protected void onHandleIntent(Intent intent) {
LukeDecision decision =
(LukeDecision)intent.getSerializableExtra(...);
if (decision != null) {
makeNetworkCall(decision);
}
...
}

37. public class NowIntentService extends IntentService {
private void makeNetworkCall(LukeDecision decision) {
boolean isCompleted = false;
if(StarWarsUtils.isNetworkActive()) {
isCompleted = doingNetworkCommunication();
}
...
}

38. public class NowIntentService extends IntentService {
private void makeNetworkCall(LukeDecision decision) {
...
if (!isCompleted) {
StarWarsUtils.addRetryTask(decision, this);
return;
}
...
}

39. How we will retry the request if it’s failed?

40. Connectivity Manager

41. AndroidManifest.xml
<receiver android:name=".ConnectivityChangeReceiver">
<intent-filter>
<action
android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
</receiver>

42. public void onReceive(Context context, Intent intent) {
LukeDecision decisionToRetry =
StarWarsUtils.getDecisionToRetry(context);
StarWarsUtils.makeDecision(decisionToRetry, context);
}
public class ConnectivityChangeReceiver extends
WakefulBroadcastReceiver

44. Han Solo
reporting to Rebels

46. public class FinalBattleActivity extends
AppCompatActivity
protected void onCreate(Bundle savedInstanceState) {
...
scheduleHanSoloReport();
...
}

47. public class FinalBattleActivity extends AppCompatActivity
private void scheduleHanSoloReport() {
AlarmManager alarmManager = (AlarmManager)
getSystemService(ALARM_SERVICE);
PendingIntent broadcast = getPendingIntent();
alarmManager.setRepeating(
AlarmManager.RTC_WAKEUP,
System.currentTimeMillis(),
ONE_MINUTE,
broadcast);
}

48. public class HanSoloReceiver
public void onReceive(Context context, Intent intent) {
LocationManager locationService = (LocationManager)
context.getSystemService(Context.LOCATION_SERVICE);
PendingIntent pendingIntent = getPendingIntent(context);
String provider = getLocationProvider(locationService);
locationService.requestSingleUpdate(provider, pendingIntent);
}

49. public class NowIntentService extends IntentService {
@Override protected void onHandleIntent(Intent intent) {
...
Location HanSoloLocation =
intent.getParcelableExtra(LocationManager.KEY_LOCATION_CHANGED);
if (HanSoloLocation != null) {
checkIfRebelsReady(HanSoloLocation);
}
}

50. RebelService

51. public class RebelService extends Service implements
Handler.Callback
public void onCreate() {
handlerThread = new HandlerThread("RebelServiceHandlerThread");
handlerThread.start();
Looper looper = handlerThread.getLooper();
handler = new Handler(looper, this);
handler.sendEmptyMessage(WHAT_MAKE_NETWORK_REQUEST);
}

52. public class RebelService extends Service implements
Handler.Callback
@Override public boolean handleMessage(Message msg) {
StarWarsUtils.doingNetworkCommunication();
handler.sendEmptyMessageDelayed(
WHAT_MAKE_NETWORK_REQUEST,
DELAY_MILLIS);
return true;
}

53. So what is affected by Doze my app?

54. What is affected
- Pending network transactions will never be fired...
- Han Solo Alarms will be postponed.
- No location updates
But...

55. There is still some place for...

56. JobScheduler/GCMNetworkManager

57. What?
Schedule the task to execute it when certain conditions
met.
(charging, idle, connected to a network or connected to
an unmetered network)

58. Why two?
JobScheduler was introduced in API >= 21 (Lollipop).
GCMNetworkManager - is part of GCM package. When using on
devices >= 21, use JobScheduler underneath.

59. build.gradle
dependencies {
...
compile 'com.google.android.gms:play-services-gcm:9.4.0'
...
}

60. public class StarWarsUtilities
void addRetryTask(LukeDecision decision,Context context){
GcmNetworkManager gcmNetworkManager =
GcmNetworkManager.getInstance(context);
…
}

61. public class StarWarsUtilities
Task task = new
OneoffTask.Builder().setService(BestTimeService.class)
.setExecutionWindow(0, 30)
.setTag(BestTimeService.LUKE_DECISION)
.setUpdateCurrent(false)
.setRequiredNetwork(Task.NETWORK_STATE_CONNECTED)
.setRequiresCharging(false)
.setExtras(bundle)
.build();

62. public class StarWarsUtilities
void addRetryTask(LukeDecision decision,Context context){
...
gcmNetworkManager.schedule(task);
}

63. AndroidManifest.xml
<service
android:name=".BestTimeService"
android:permission="com.google.android.gms.permission.BIND_NETWORK_TASK_SERVICE"
android:exported="true">
<intent-filter>
<action android:name="com.google.android.gms.gcm.ACTION_TASK_READY"/>
</intent-filter>
</service>

64. BestTimeService.java
/**
* Task run by GcmNetworkManager when all the
requirements of the scheduled
* task are met.
*/
public class BestTimeService extends GcmTaskService {
...
}

65. BestTimeService.java
@Override public int onRunTask(TaskParams taskParams) {
switch (taskParams.getTag()) {
case LUKE_DECISION:
...
return GcmNetworkManager.RESULT_SUCCESS;
case HAN_SOLO_LOCATION:
...
return GcmNetworkManager.RESULT_RESCHEDULE;
default:
return GcmNetworkManager.RESULT_FAILURE;
}
}

66. BestTimeService.java
public int onRunTask(TaskParams taskParams) {
…
case LUKE_DECISION:
Bundle extras = taskParams.getExtras();
LukeDecision decision = (LukeDecision)
extras.getSerializable(...);
StarWarsUtils.makeDecision(decision, this);
return GcmNetworkManager.RESULT_SUCCESS;
…
}

67. Han Solo Recurring Location task?

68. Task task = new PeriodicTask.Builder()
.setService(BestTimeService.class)
.setPeriod(SIXTY_SEC)
.setFlex(10)
.setTag(BestTimeService.HAN_SOLO_LOCATION)
.setPersisted(true)
.build();
public class FinalBattleActivity

69. BestTimeService.java
public int onRunTask(TaskParams taskParams) {
…
case HAN_SOLO_LOCATION:
.. request location...
return GcmNetworkManager.RESULT_SUCCESS;
…
}

70. Canceling Task
mGcmNetworkManager.cancelAllTasks(BestTimeService.class);
mGcmNetworkManager.cancelTask(
TAG,
BestTimeService.class
);

71. There is a problem hiding here

72. Not all devices shipped with Play Services
int resultCode =
GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (resultCode == ConnectionResult.SUCCESS) {
mGcmNetworkManager.schedule(task);
} else {
// Deal with this networking task some other way
}

73. When Google Play updated it removes all
scheduled periodic tasks
public class BestTimeService extends GcmTaskService {
@Override
public void onInitializeTasks() {
super.onInitializeTasks();
// Reschedule removed tasks here
}
}

74. Can we do better?

75. FCM/GCM with High Priority
{
"to" : "...",
"priority" : "high",
"notification" : {
...
},
"data" : {
...
}
}

76. AndroidManifest.xml
<service
android:name=".RebelsMessagingService">
<intent-filter>
<action
android:name="com.google.firebase.MESSAGING_EVENT"/>
</intent-filter>
</service>

77. public class RebelsMessagingService extends FirebaseMessagingService
@Override public void onMessageReceived(RemoteMessage
remoteMessage) {
Intent intent = new Intent(HanSoloReceiver.ACTION);
LocalBroadcastManager.
getInstance(this).
sendBroadcast(intent);
}

78. Some dirty tricks.
Be aware when using it…

79. public class RebelService extends Service implements
Handler.Callback
public boolean handleMessage(Message msg) {
StarWarsUtils.doingNetworkCommunication());
handler.sendEmptyMessageDelayed(
WHAT_MAKE_NETWORK_REQUEST,
DELAY_MILLIS);
return true;
}

80. public class RebelService extends Service implements
Handler.Callback
public void onCreate() {
Notification notification =
...
startForeground(101, notification);
}

82. Yonatan Levin
Google Developer Expert
levin.yonatan
parahall