API 26 migration Master Issue

[mzorz]

comes from #7506, master migration branch

Previous PRs that are base to the changes below:

• Bumped Google Play Services library version to latest bumped play services lib version #7595
• Implemented Notification Channels for Android O Issue/5530 basic notification channels android o #7593
• Removed Sights & Sounds category from Notifications Settings for Anroid O+ removes the Sight And Sounds category on API26+ #7611
• Push notifications GCM Token Refresh implementation migration to JobIntentService Api26/jobschedule token refresh #7598

Here's the ToDo list re: services

Services that are already prepared for Android O (using foreground notifications)

• UploadService
• LoginWpComService
• SiteCreationService

Services that are not affected by new background execution limits

(https://developer.android.com/about/versions/oreo/background.html)

Bound services are not affected
These rules do not affect bound services in any way. If your app defines a bound service, other components can bind to that service whether or not your app is in the foreground.

• MediaDeleteService
• SuggestionService

Services triggered from a Notification Action are not subject to background limits as well.
https://developer.android.com/about/versions/oreo/background.html#services

Under certain circumstances, a background app is placed on a temporary whitelist for several minutes. While an app is on the whitelist, it can launch services without limitation, and its background services are permitted to run. An app is placed on the whitelist when it handles a task that's visible to the user, such as:
[…]
- Executing a PendingIntent from a notification.
[…]

• NotificationsProcessingService

Started services (either Service or IntentService) that don’t need be re-written given how they’re being used:

• PlanUpdateService (Service, uses network connection, but is tied to PlansActivity's onStart() and onStop() methods)
• ReaderCommentService (Service, uses network connection). Only used in NotificationsDetailListFragment, and started/stopped in onStart()/onPause().

Other

• GCMMessageService: extends Google Play Services’ GcmListenerService so it shouldn’t need any changes (need double check, updated in bumped play services lib version #7595)
• InstanceIDService: extends Google Play Services’ InstanceIDListenerService, same as above

Candidate started services (either Service or IntentService) that need be re-written as JobIntentService or something else:

• Api26/jobschedule stats service #7617 StatsService (Service, uses network connection, this might be the most complex, definitely needs to be a Job as is used by the StatsWidgetProvider as well)
• Api26/jobschedule reader update service #7603 ReaderUpdateService (Service, uses network connection, it is started i.e. when Login ends, so needs to run in the background as a Job)
• Api26/jobschedule reader post service #7607 ReaderPostService (Service, uses network connection. Used in ReaderPostPagerActivity and ReaderPostListFragment to fetch and populate the screen; connected through EventBus, wondering if we need an AsyncTask here rather than anything else?)
• Api26/jobschedule reader search service #7608 ReaderSearchService (Service, uses network connection, same as ReaderPostService the cycle is handled through EventBus, started from ReaderPostListFragment). It’s easier code wise to frame this as a JobIntentService (fewer changes), although this is probably a candidate for AsyncTask give it’s only used in this fragment alone.
• Convert PublicizeUpdateService from IntentService to JobIntentService #7605 PublicizeUpdateService (IntentService, called in PublicizeListActivity, uses network connection)
• Api26/jobschedule notifications update #7610 NotificationsUpdateService (Service, uses network connection, same as ReaderUpdateService it is started i.e. when Login ends, so needs to run in the background as a Job

Here's the ToDo list re: broadcast receivers

Broadcast Receivers

https://developer.android.com/about/versions/oreo/background.html#broadcasts
The app can no longer register for implicit broadcasts.

The list of broadcast receivers registered in the Manifest follows.

Unaffected (explicit receivers, or implicit but whitelisted receivers)

• NotificationDismissBroadcastReceiver is only used in a PendingIntent for Notifications, so these also shouldn’t be a problem.
• ShareAndDismissNotificationReceiver same as above, explicit intent.
• NotificationsPendingDraftsReceiver has the implicit broadcast filter android.intent.action.BOOT_COMPLETED, but it’s in the exception list https://developer.android.com/guide/components/broadcast-exceptions.html
• com.google.android.gms.gcm.GcmReceiver probably has been taken care of in bumped play services lib version #7595

Affected (implicit, not white-listed receivers)

• .ui.stats.StatsWidgetProvider has intent-filter android.appwidget.action.APPWIDGET_UPDATE, which is NOT white listed (https://developer.android.com/guide/components/broadcast-exceptions.html)
  We will probably have to register this one programmatically when the app wakes up.

EDIT: apparently app widgets receivers don't have a problem on API level 26, as per what can be read here: https://developer.android.com/guide/topics/appwidgets/index.html

On devices running Android 8.0 (API level 26) and higher, the launchers that allow you to create pinned shortcuts also allow you to pin app widgets onto the launcher. Similar to pinned shortcuts, these pinned widgets give users access to specific tasks in your app.

In your app, you can create a request for the system to pin a widget onto a supported launcher by completing the following sequence of steps:

Create the widget in your app's manifest file, as shown in the following snippet:

<manifest>
...
  <application>
    ...
    <receiver android:name="MyAppWidgetProvider">
        <intent-filter>
            <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
        </intent-filter>
        <meta-data android:name="android.appwidget.provider"
                   android:resource="@xml/my_appwidget_info" />
    </receiver>
  </application>
</manifest>

[mzorz]

Closing via #7506