Doo z z z z z e

With Android Marshmallow Google introduced two new power-saving modes: Doze and App Standby. True to their intent, both provide longer battery life and better performance. Their effectiveness further improved in Android Nougat. However, these modes carry some limitations developers should be aware of. To further improve power-saving Android O will be even more restrictive and disable common implicit broadcasts. Many apps rely on implicit broadcasts so if you're using those, supporting older and newer devices at the same time is going to be more challenging.

This talk will explain why these new APIs are better. We will discuss the given tools and dive into the new APIs. Finally, we will explore effective solutions to avoid duplicating code over and over again for different SDK versions.

Transcript

1. Doo z z z z z e
   Ralf Wondratschek
   @vRallev
   2017-09-04
   

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5. Doo z z z z z e
   

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6. Motivation
   

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7. Motivation
   ● Every app has some kind of repeated work
   ● Don’t waste battery unnecessarily
   ● App should still work correctly even in Doze
   mode or in App Standby
   ● App should still work on Android O
   ● Scheduling repeated work is quite a headache
   with 3 different APIs all doing similar things
   

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8. Doze & App Standby
   

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9. https://developer.android.com/images/training/doze.png
   

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10. Doze & App Standby
    ● Doze
    → Long idle battery life
    ● Doze Lite (with Android N)
    → Screen off battery life
    ● App Standby
    → Idle apps when the device is unplugged
    https://www.youtube.com/watch?v=hbLAzwhBjFE
    

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11. Doze & App Standby
    ● Special cases to interrupt Doze
    ○ High priority GCM / FCM messages
    ○ Notification interaction
    ○ SMS
    ○ Special APIs
    ○ Whitelist app
    https://www.youtube.com/watch?v=hbLAzwhBjFE
    

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12. Android O
    ● Background service limitations
    ○ Use foreground services
    ○ Android O stops background services for apps in the
    background
    ○ Can’t start background services from an app in background
    ● Broadcast removal
    ○ Whitelist
    ○ android.net.conn.CONNECTIVITY_CHANGE
    https://developer.android.com/preview/features/background.html
    

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13. Android O - Custom Intents
    
    

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14. Android O - Custom Intents
    
    android:label="@string/app_name"
    android:description="@string/description"
    android:protectionLevel="signature" />
    
    

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15. Android O - Custom Intents
    
    android:label="@string/app_name"
    android:description="@string/description"
    android:protectionLevel="signature" />
    
    fun Context.sendEvernoteBroadcast(intent: Intent) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    sendBroadcast(intent, EvernoteContract.PERMISSION)
    } else {
    sendBroadcast(intent)
    }
    }
    

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16. Demo - Reminder app
    https://github.com/vRallev/job-sample
    

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17. Requirements
    ● Show the reminder in a notification
    ● Sync reminders with the server
    ● Support all devices
    ● Be a good citizen
    

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18. Reminder job
    ● Must be exact
    ● Can have multiple at the same time
    ● AlarmManager is the correct API
    

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19. AlarmManager
    + Available on all devices
    + Easy to send broadcast to start a service delayed
    - API behavior differs between platform versions
    - A lot of boilerplate
    - Device state ignored
    - …
    

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20. Reminder job
    android:name=".reminder.ReminderReceiver"
    android:exported="false"/>
    public class ReminderReceiver extends BroadcastReceiver {
    private static final String EXTRA_ID = "EXTRA_ID";
    @Override
    public void onReceive(Context context, Intent intent) {
    int id = intent.getIntExtra(EXTRA_ID, -1);
    if (id < 0) {
    return;
    }
    Reminder reminder = ReminderEngine.instance().getReminderById(id);
    if (reminder != null) {
    ReminderEngine.instance().showReminder(reminder);
    }
    }
    }
    

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21. Reminder job
    android:name=".reminder.ReminderReceiver"
    android:exported="false"/>
    public class ReminderReceiver extends BroadcastReceiver {
    private static final String EXTRA_ID = "EXTRA_ID";
    @Override
    public void onReceive(Context context, Intent intent) {
    int id = intent.getIntExtra(EXTRA_ID, -1);
    if (id < 0) {
    return;
    }
    Reminder reminder = ReminderEngine.instance().getReminderById(id);
    if (reminder != null) {
    ReminderEngine.instance().showReminder(reminder);
    }
    }
    }
    

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22. API 14-18
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent);
    }
    

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23. API 14-18
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent);
    }
    

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24. API 19-22
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent);
    }
    

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25. API 19-22
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.setExact(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent);
    }
    

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26. API 23-26
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.setExact(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent);
    }
    

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27. API 23-26
    public static void schedule(Context context, Reminder reminder) {
    Intent intent = new Intent(context, ReminderReceiver.class);
    intent.putExtra(EXTRA_ID, reminder.getId());
    int requestCode = reminder.getId();
    int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT;
    PendingIntent pendingIntent = PendingIntent
    .getBroadcast(context, requestCode, intent, flags);
    AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP,
    reminder.getTimestamp(), pendingIntent);
    }
    

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28. Reminder job
    public static void schedule(Context context, Reminder reminder) {
    // …
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
    manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, when, pendingIntent);
    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
    manager.setExact(AlarmManager.RTC_WAKEUP, when, pendingIntent);
    } else {
    manager.set(AlarmManager.RTC_WAKEUP, when, pendingIntent);
    }
    }
    

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29. AlarmManager
    https://plus.google.com/+AndroidDevelopers/posts/GdNrQciPwqo
    

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30. Sync job
    ● Can be inexact, but must be repeating
    ● Run job only on an unmetered network and only
    if device is charging
    ● Don’t wake up the device to sync data
    ● JobScheduler and GCM Network Manager work
    best, AlarmManager is fallback
    

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31. JobScheduler
    + Easy to use with fluent API
    + Respects device state
    - Only on API 21+
    (some features only API 24+ or 26+)
    - Platform bugs
    - Still a lot of boilerplate code
    

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32. API 21-23
    
    
    android:name=".sync.SyncJob"
    android:permission="android.permission.BIND_JOB_SERVICE"/>
    
    

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33. public class SyncJob extends JobService {
    @Override
    public boolean onStartJob(JobParameters params) {
    // called on main thread
    new Thread(() -> {
    try {
    new SyncEngine().syncReminders();
    } catch (IOException e) {
    e.printStackTrace();
    } finally {
    jobFinished(params, false); // don't forget to call
    }
    }).start();
    return true; // we have background work
    }
    @Override
    public boolean onStopJob(JobParameters params) {
    return false; // don't reschedule
    }
    }
    API 21-23
    

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34. private static final int JOB_ID = 1;
    public static void schedule(Context context) {
    long interval = TimeUnit.HOURS.toMillis(6);
    JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class))
    .setRequiresCharging(true)
    .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED)
    .setPersisted(true)
    .setPeriodic(interval)
    .build();
    JobScheduler jobScheduler = (JobScheduler) context
    .getSystemService(Context.JOB_SCHEDULER_SERVICE);
    jobScheduler.schedule(jobInfo);
    }
    API 21-23
    

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35. private static final int JOB_ID = 1;
    public static void schedule(Context context) {
    long interval = TimeUnit.HOURS.toMillis(6);
    JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class))
    .setRequiresCharging(true)
    .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED)
    .setPersisted(true)
    .setPeriodic(interval)
    .build();
    JobScheduler jobScheduler = (JobScheduler) context
    .getSystemService(Context.JOB_SCHEDULER_SERVICE);
    jobScheduler.schedule(jobInfo);
    }
    API 21-23
    

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36. private static final int JOB_ID = 1;
    public static void schedule(Context context) {
    long interval = TimeUnit.HOURS.toMillis(6);
    long flex = TimeUnit.HOURS.toMillis(3);
    JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class))
    .setRequiresCharging(true)
    .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED)
    .setPersisted(true)
    .setPeriodic(interval, flex)
    .build();
    JobScheduler jobScheduler = (JobScheduler) context
    .getSystemService(Context.JOB_SCHEDULER_SERVICE);
    jobScheduler.schedule(jobInfo);
    }
    API 24-26
    

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37. Flex parameter explained
    

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38. Flex parameter explained
    

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39. GCM Network Manager
    + Similar API like JobScheduler
    + minSdkVersion 9
    - Part of Google’s Play Services SDK
    - Can’t be used without Play Services being
    pre-installed (most Chinese devices)
    - API contains some gotchas
    

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40. android:name=".sync.SyncJob"
    android:exported="true"
    android:permission="com.google.android.gms.permission.BIND_NETWORK_TASK_SERVICE">
    
    
    
    
    With Google Play Services
    

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41. public class SyncJob extends GcmTaskService {
    @Override
    public int onRunTask(TaskParams taskParams) {
    try {
    new SyncEngine().syncReminders();
    return GcmNetworkManager.RESULT_SUCCESS;
    } catch (IOException e) {
    e.printStackTrace();
    return GcmNetworkManager.RESULT_FAILURE;
    }
    }
    }
    With Google Play Services
    

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42. private static final String TAG = "SyncJob";
    public void schedule(Context context) {
    long interval = TimeUnit.HOURS.toMillis(6);
    long flex = TimeUnit.HOURS.toMillis(3);
    PeriodicTask task = new PeriodicTask.Builder()
    .setTag(TAG)
    .setService(SyncJob.class)
    .setRequiresCharging(true)
    .setRequiredNetwork(Task.NETWORK_STATE_UNMETERED)
    .setPersisted(true)
    .setUpdateCurrent(true)
    .setPeriod(interval / 1_000)
    .setFlex(flex / 1_000)
    .build();
    GcmNetworkManager.getInstance(context).schedule(task);
    }
    With Google Play Services
    

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43. private static final String TAG = "SyncJob";
    public void schedule(Context context) {
    long interval = TimeUnit.HOURS.toMillis(6);
    long flex = TimeUnit.HOURS.toMillis(3);
    PeriodicTask task = new PeriodicTask.Builder()
    .setTag(TAG)
    .setService(SyncJob.class)
    .setRequiresCharging(true)
    .setRequiredNetwork(Task.NETWORK_STATE_UNMETERED)
    .setPersisted(true)
    .setUpdateCurrent(true)
    .setPeriod(interval / 1_000)
    .setFlex(flex / 1_000)
    .build();
    GcmNetworkManager.getInstance(context).schedule(task);
    }
    With Google Play Services
    

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44. API 14-19
    ● Use AlarmManager
    ● As much fun as the reminder job…
    

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45. Sync job
    public void schedule(Context context) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
    scheduleWithJobScheduler24(context);
    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
    scheduleWithJobScheduler21(context);
    } else if (GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context)
    == ConnectionResult.SUCCESS) {
    scheduleWithGcmNetworkManager(context);
    } else {
    scheduleWithAlarmManager(context);
    }
    }
    

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46. (Firebase JobDispatcher)
    + Wrapper for job scheduling engines
    - Setup is difficult
    - Library not maintained
    - Only GCM NetworkManager supported
    - Many open issues
    → I would not recommend using it
    

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47. (JobIntentService)
    + Replacement for IntentService respecting the
    App state (uses JobScheduler on Android O+)
    + Handles wakelocks for you
    - Only for running tasks now
    - Once a job is enqueued, you cannot cancel it
    

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48. Conclusion
    ● A lot of boilerplate to achieve something that
    should be simple
    

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49. Conclusion
    ● A lot of boilerplate to achieve something that
    should be simple
    ● It should be much easier
    

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50. android-job
    Fork
    me
    on
    GitHub
    github.com/evernote/
    

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51. android-job
    ● Single API to use the JobSchduler, GCM Network
    Manager and AlarmManager
    ● All API 26 features supported
    ● Automatically chooses best API to run a job
    ● Less boilerplate, e.g. no manifest entry needed
    ● No reflection used
    ● Maintained and improved continuously
    ● … and more
    

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52. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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53. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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54. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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55. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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56. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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57. API
    PersistableBundleCompat extras = new PersistableBundleCompat();
    extras.putString("key", "Hello world");
    Bundle transientExtras = new Bundle();
    transientExtras.putParcelable("parcelable", Uri.parse("file://path"));
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    

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58. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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59. API
    int jobId = new JobRequest.Builder(ReminderJob.TAG)
    .setExecutionWindow(30_000L, 40_000L)
    .setExact(30_000L)
    .startNow()
    .setPeriodic(TimeUnit.HOURS.toMillis(3), TimeUnit.HOURS.toMillis(1))
    .setBackoffCriteria(5_000L, JobRequest.BackoffPolicy.EXPONENTIAL)
    .setRequiresCharging(true)
    .setRequiresDeviceIdle(false)
    .setRequiredNetworkType(JobRequest.NetworkType.CONNECTED)
    .setRequiresBatteryNotLow(true)
    .setRequiresStorageNotLow(true)
    .setRequirementsEnforced(true)
    .setExtras(extras)
    .setTransientExtras(transientExtras)
    .setUpdateCurrent(true)
    .build()
    .schedule();
    

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60. Setup
    dependencies {
    compile 'com.evernote:android-job:1.2.0'
    }
    public class App extends Application {
    @Override
    public void onCreate() {
    super.onCreate();
    JobManager.create(this).addJobCreator(new ReminderJobCreator());
    }
    }
    

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61. Setup
    dependencies {
    compile 'com.evernote:android-job:1.2.0'
    }
    public class App extends Application {
    @Override
    public void onCreate() {
    super.onCreate();
    JobManager.create(this).addJobCreator(new ReminderJobCreator());
    }
    }
    

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62. Setup
    public class ReminderJobCreator implements JobCreator {
    @Override
    public Job create(String tag) {
    switch (tag) {
    case ReminderJob.TAG:
    return new ReminderJob();
    case SyncJob.TAG:
    return new SyncJob();
    default:
    return null;
    }
    }
    }
    

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63. Reminder job
    public class ReminderJob extends Job {
    public static final String TAG = "ReminderJob";
    private static final String EXTRA_ID = "EXTRA_ID";
    @NonNull
    @Override
    protected Result onRunJob(Params params) {
    int id = params.getExtras().getInt(EXTRA_ID, -1);
    Reminder reminder = ReminderEngine.instance().getReminderById(id);
    if (reminder == null) {
    return Result.FAILURE;
    }
    ReminderEngine.instance().showReminder(reminder);
    return Result.SUCCESS;
    }
    }
    

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64. Reminder job
    public class ReminderJob extends Job {
    public static final String TAG = "ReminderJob";
    private static final String EXTRA_ID = "EXTRA_ID";
    @NonNull
    @Override
    protected Result onRunJob(Params params) {
    int id = params.getExtras().getInt(EXTRA_ID, -1);
    Reminder reminder = ReminderEngine.instance().getReminderById(id);
    if (reminder == null) {
    return Result.FAILURE;
    }
    ReminderEngine.instance().showReminder(reminder);
    return Result.SUCCESS;
    }
    }
    

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65. public static int schedule(@NonNull Reminder reminder) {
    PersistableBundleCompat extras = new PersistableBundleCompat();
    extras.putInt(EXTRA_ID, reminder.getId());
    long time = Math.max(1L, reminder.getTimestamp() - System.currentTimeMillis());
    return new JobRequest.Builder(TAG)
    .setExact(time)
    .setExtras(extras)
    .setUpdateCurrent(false)
    .build()
    .schedule();
    }
    Reminder job
    

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66. Reminder job
    public static int schedule(@NonNull Reminder reminder) {
    PersistableBundleCompat extras = new PersistableBundleCompat();
    extras.putInt(EXTRA_ID, reminder.getId());
    long time = Math.max(1L, reminder.getTimestamp() - System.currentTimeMillis());
    return new JobRequest.Builder(TAG)
    .setExact(time)
    .setExtras(extras)
    .setUpdateCurrent(false)
    .build()
    .schedule();
    }
    

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67. Sync job
    public class SyncJob extends Job {
    public static final String TAG = "SyncJob";
    @NonNull
    @Override
    protected Result onRunJob(Params params) {
    new SyncEngine().syncReminders();
    return Result.SUCCESS;
    }
    }
    

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68. Sync job
    public static int schedule() {
    Set jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG);
    if (!jobRequests.isEmpty()) {
    return jobRequests.iterator().next().getJobId();
    }
    long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours
    long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again
    return new JobRequest.Builder(TAG)
    .setPeriodic(interval, flex)
    .setUpdateCurrent(true)
    .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED)
    .setRequiresCharging(true)
    .setRequirementsEnforced(true)
    .build()
    .schedule();
    }
    

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69. Sync job
    public static int schedule() {
    Set jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG);
    if (!jobRequests.isEmpty()) {
    return jobRequests.iterator().next().getJobId();
    }
    long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours
    long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again
    return new JobRequest.Builder(TAG)
    .setPeriodic(interval, flex)
    .setUpdateCurrent(true)
    .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED)
    .setRequiresCharging(true)
    .setRequirementsEnforced(true)
    .build()
    .schedule();
    }
    

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70. Sync job
    public static int schedule() {
    Set jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG);
    if (!jobRequests.isEmpty()) {
    return jobRequests.iterator().next().getJobId();
    }
    long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours
    long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again
    return new JobRequest.Builder(TAG)
    .setPeriodic(interval, flex)
    .setUpdateCurrent(true)
    .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED)
    .setRequiresCharging(true)
    .setRequirementsEnforced(true)
    .build()
    .schedule();
    }
    

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71. Sync job
    public static int schedule() {
    Set jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG);
    if (!jobRequests.isEmpty()) {
    return jobRequests.iterator().next().getJobId();
    }
    long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours
    long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again
    return new JobRequest.Builder(TAG)
    .setPeriodic(interval, flex)
    .setUpdateCurrent(true)
    .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED)
    .setRequiresCharging(true)
    .setRequirementsEnforced(true)
    .build()
    .schedule();
    }
    

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72. Sync job
    public static int schedule() {
    Set jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG);
    if (!jobRequests.isEmpty()) {
    return jobRequests.iterator().next().getJobId();
    }
    long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours
    long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again
    return new JobRequest.Builder(TAG)
    .setPeriodic(interval, flex)
    .setUpdateCurrent(true)
    .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED)
    .setRequiresCharging(true)
    .setRequirementsEnforced(true)
    .build()
    .schedule();
    }
    

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73. Who is using it?
    

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74. FAQ
    Which API is used?
    ● Exact job → AlarmManager
    ● API 21+ → JobScheduler
    ● Play Services installed → GcmNetworkManager
    ● Else → AlarmManager
    

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75. FAQ
    What happens after a reboot?
    ● All jobs are rescheduled if necessary
    → even after a force close
    → even after the Play Services were updated
    → even after the app was updated
    

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76. FAQ
    My periodic jobs aren’t running as expected.
    ● Keep Doze and the system in mind
    

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77. FAQ
    How can I run an asynchronous operation?
    ● Block the background thread
    override fun onRunJob(params: Params): Result {
    //...
    observable
    .filter { it.didItemsChange }
    ...
    .blockingGet()
    return Result.SUCCESS
    }
    

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78. FAQ
    What happens if my job crashes?
    ● The result is treated as failure and the job is not
    rescheduled
    

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79. FAQ
    Can I reuse jobs?
    ● No, always create a new instance
    in your job creator
    

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80. FAQ
    What are transient jobs?
    ● Jobs are persisted whereas transient jobs will
    only run as long as your process keeps running
    val bundle = Bundle().apply {
    putParcelable("uri", Uri.parse("file://something"))
    putSerializable("enum", JobRequest.NetworkType.CONNECTED)
    }
    JobRequest.Builder(TAG)
    .startNow()
    .setTransientExtras(bundle)
    .build()
    .schedule()
    

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81. FAQ
    How can I run a job once a day?
    ● Use the DailyJob class
    

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82. FAQ
    How can I run a job once a day?
    class CollectCleanUpJob : DailyJob() {
    companion object {
    const val TAG = "CollectCleanUpJob"
    fun schedule() {
    val builder = JobRequest.Builder(TAG).setRequiresDeviceIdle(true)
    DailyJob.schedule(builder, TimeUnit.HOURS.toMillis(1), TimeUnit.HOURS.toMillis(7))
    }
    }
    override fun onRunDailyJob(params: Params): DailyJobResult {
    return DailyJobResult.SUCCESS
    }
    }
    

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83. FAQ
    How can I run a job once a day?
    class CollectCleanUpJob : DailyJob() {
    companion object {
    const val TAG = "CollectCleanUpJob"
    fun schedule() {
    val builder = JobRequest.Builder(TAG).setRequiresDeviceIdle(true)
    DailyJob.schedule(builder, TimeUnit.HOURS.toMillis(1), TimeUnit.HOURS.toMillis(7))
    }
    }
    override fun onRunDailyJob(params: Params): DailyJobResult {
    return DailyJobResult.SUCCESS
    }
    }
    

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84. FAQ
    How can I run a job once a day?
    class CollectCleanUpJob : DailyJob() {
    companion object {
    const val TAG = "CollectCleanUpJob"
    fun schedule() {
    val builder = JobRequest.Builder(TAG).setRequiresDeviceIdle(true)
    DailyJob.schedule(builder, TimeUnit.HOURS.toMillis(1), TimeUnit.HOURS.toMillis(7))
    }
    }
    override fun onRunDailyJob(params: Params): DailyJobResult {
    return DailyJobResult.SUCCESS
    }
    }
    

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85. FAQ
    How can I test jobs?
    JobRequest.Builder(TAG)
    .apply {
    if (type == IMMEDIATELY) {
    startNow()
    } else {
    setExecutionWindow(TimeUnit.SECONDS.toMillis(30),
    TimeUnit.SECONDS.toMillis(60))
    }
    }
    .setExtras(bundle)
    .build()
    .schedule()
    

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86. FAQ
    How can I test jobs?
    

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87. FAQ
    How can I test jobs?
    > adb shell dumpsys jobscheduler | grep com.company.app
    JOB #u0a84/1: 3520a16 com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    u0a84 tag=*job*/com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    Source: uid=u0a84 user=0 pkg=com.evernote.android.job.demo.gcm
    Service: com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    JOB #u0a84/2: c052f97 com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    u0a84 tag=*job*/com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    Source: uid=u0a84 user=0 pkg=com.evernote.android.job.demo.gcm
    Service: com.evernote.android.job.demo.gcm/com.evernote.android.job.v21.PlatformJobService
    > adb shell cmd jobscheduler run -f com.company.app 1
    

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88. FAQ
    How can I test Doze?
    > adb shell dumpsys deviceidle help
    > adb shell dumpsys deviceidle force-idle [light|deep]
    > adb shell dumpsys deviceidle unforce
    

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89. android-job
    Tips & Tricks
    ● Look at the samples in the README
    ● Read the FAQ
    ● Uncertain? Having problems?
    → Create an issue
    

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90. Conclusion
    ● Android APIs force you to
    ○ do the same thing multiple times
    ○ write a lot of boilerplate
    ○ catch many gotchas
    ● android-job to the rescue
    

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91. twitter.com/vRallev
    google.com/+vRallev
    Doo z z z z z e
    

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