Developing for Amazon Fire TV Devices Running Fire OS 7
Fire OS 7 is based on Android 9 Pie. You can ensure your app's compatibility with Fire OS 7 by following these guidelines.
- Devices running Fire OS 7 and previous fire OS releases
- Android changes in Fire OS 7
- Fire OS 7 parity with Android 9
- Targeting your app for Fire OS 7 devices
- Testing your app's compatibility on Fire OS 7 devices
- What to set for minSdkVersion and targetSdkVersion
- Understanding how minSdkVersion affects supported devices
- Notifications in Fire OS 7
- Amazon Device Messaging (ADM) compatibility
- Wake lock changes
- Support
Devices running Fire OS 7 and previous fire OS releases
Fire OS 7 is based on Android 9 Pie (API level 28). Fire OS 7 was initially released for some Fire TV devices in 2019.
Most 2018 Amazon Fire TV devices run on Fire OS 6, which is based on Android Nougat (Android 7.1.2, level 25). Even older Fire TV devices are on Fire OS 5 (Android 5.1, level 22). In general, the Fire OS version of older devices isn't upleveled.
For a detailed list of Fire TV devices and versions, see Fire OS Versions.
Android changes in Fire OS 7
The upgrade from Fire OS 6 to Fire OS 7 requires a transition from Nougat (Android 7.1.2) through Oreo (Android 8.0) to Pie (Android 9).
Changes introduced in Android 8.0 and Android 9 require you to make code changes in your app before the app will work correctly on Fire OS 7 devices.
Android 8.0 changes
Major changes in Android 8.0 include the following:
-
Notification Channels: All notifications (which includes recommendations and partner-managed recommendations) must be associated with a channel. For information about channels, see Android training for Notification Channels. For sample code and additional details, see the Notifications in Fire OS 7 section below.
-
Background Services: Android 8.0 limits the use of background services. As a result, any apps using background services to refresh their recommendations will fail to refresh the recommendations on FOS 7. Android recommends using JobSchedulers as a workaround for the limitation with background services. See Background Services.
-
Native Libraries: Native libraries no longer load if they contain any load segment that is both writable and executable.
-
Permissions: Apps need to explicitly request each permission, even within the same permission group.
-
MediaSession events: Your app needs to use MediaSession correctly to handle audio. See the Android 8.0 documentation on Finding a media session. When Android handles events, if the foreground activity doesn't have an active media session to handle the event, Android will look for other media sessions. See also Requirements for Multimedia Apps on Fire TV.
You can read about most of these changes in Android 8.0 Behavior Changes.
Android 9 changes
Major changes in Android 9 include only the following:
- Privacy changes: Apps will have restricted access to wifi. Apps will have limited access to user inputs and sensor data while running in the background.
You can read about these changes in Behavior changes: all apps (Pie).
Fire OS 7 parity with Android 9
All features implemented in FOS 7 are at feature parity with Android 9. This doesn't necessarily mean that everything in Android 9 is available in FOS 7, but for those Android 9 features implemented in FOS 7, they have parity. Some Android 9 features, such as split-Screen, notification dots, and adaptive icons, aren't supported in FOS 7.
Also, remember that although Fire OS 7 has parity with Android 9, you can't use Google services on Amazon Fire devices. Instead, you must use the Apps & Games Services SDKs for the services you need (such as in-app purchasing). See Amazon Fire TV Development Versus Android TV Development for more details.
Targeting your app for Fire OS 7 devices
Users might run your app on a Fire OS 5, Fire OS 6, or Fire OS 7 device. To maximize your app compatibility with the Fire OS version on the device, we recommend that you target the device based on the SDK level.
In your code, you can check whether the Build.VERSION.SDK_INT
is greater than or equal to 28
(The Android 9 API level) to target Fire OS 7 devices.
See Identify Fire TV Devices for more details. Also see Supporting Different Platform Versions in the Android documentation.
Testing your app's compatibility on Fire OS 7 devices
Currently, you can test your app's compatibility with Fire OS 7 by connecting to an actual device.
What to set for minSdkVersion and targetSdkVersion
Set your minSdkVersion
to the minimum API level for the applicable Fire OS version.
Fire OS Version | minSdkVersion |
---|---|
Fire OS 5 | 22 |
Fire OS 6 | 25 |
Fire OS 7 | 28 |
Set the targetSdkVersion
to the highest API level that you've tested your app against.
See Device Filtering and Compatibility for more information on minimum API level requirements.
Understanding how minSdkVersion affects supported devices
In your app manifest (or build.gradle
file), the minSdkVersion
attribute sets the minimum SDK level that your app needs in order to function properly. (Devices that don't support that API level won't allow the app to be installed on that device — this is how device filtering and compatibility works with the Appstore.)
Fire OS 5 devices are based on API level 22 (Lollipop 5.1). Fire OS 7 devices are based on API level 28 (Android 9). By setting the minSdkVersion
to 22, you're saying that your app requires the device to have at least API level 22 for it to function properly.
By setting the minSdkVersion
to 22, your app will also install on any devices that have a higher API level (such as 28), because Android levels are backwards-compatible. API level 28 usually includes all the APIs for levels 1 through 28 (each release adds to the previous).
However, suppose you want to take advantage of APIs in Android 9 (API level 28). If you set your minSdkVersion
to 22, your app will install on Fire OS 5 devices that don't have level 28 APIs. Therefore, you must code in a defensive way to check the device level and fall back to alternatives if the device doesn't support that API level. Your code might look something like this:
targetSdkVersion
if (Build.VERSION.SDK_INT >= 28) {
Log.v(TAG, "Yes, this is an API level 28 or higher device");
} else {
Log.v(TAG, "No, this is not an API level 28 or higher device");
}
This code checks whether the device's API level is greater than or equal to 28, and if so, runs the code. If not, it falls back on else
logic.
By default, if the targetSdkVersion
is not specified, it uses the same value as the minSdkVersion
. The targetSdkVersion
lets you set the latest API level that you have tested your app against. Based on this value, Android will ensure proper behavior on devices at this level.
For example, if you set your targetSdkVersion
to 23 or higher (Marshmallow's release), Android will apply the runtime permission checking features included in Marshmallow. But if targetSdkVersion
is lower than 23 (prior to the runtime permission checking release in Marshmallow), Android will not apply this behavior to your app.
Although not recommended, if you need to prevent older apps from appearing on Fire OS 7 devices, you may set maxSdkVersion
to Fire OS 5 (22).
For more information, see the following:
<uses-sdk>
- Supporting Different Platform Versions
- Picking your compileSdkVersion, minSdkVersion, and targetSdkVersion
Notifications in Fire OS 7
As of Android Level 8.0 (API level 26), notifications that your app sends must be assigned to a channel. (Recommendations are a kind of notification.) If your app sends notifications or recommendations, you must create a channel and associate the channel with the notification. A notification without a channel ID will be dropped.
At a high-level, to add a channel to a notification, you do the following:
- Step 1: Create the notification channel and register it with the notification manager.
- Step 2: Set the channel ID for the notification, using one of the following methods:
The following sections provide more detail and code samples.
Step 1: Create the notification channel and register it with the notification manager
The following is from Create a notification channel in the Android documentation:
Create a notification channel
To create a notification channel, follow these steps:
- Construct a
NotificationChannel
object with a unique channel ID, a user-visible name, and an importance level.- Optionally, specify the description that the user sees in the system settings with
setDescription
.Register the notification channel by passing it to
createNotificationChannel
.private void createNotificationChannel() { // Create the NotificationChannel, but only on API 26+ because // the NotificationChannel class is new and not in the support library if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) { CharSequence name = getString(R.string.channel_name); String description = getString(R.string.channel_description); int importance = NotificationManager.IMPORTANCE_DEFAULT; NotificationChannel channel = new NotificationChannel(CHANNEL_ID, name, importance); channel.setDescription(description); // Register the channel with the system; you can't change the importance // or other notification behaviors after this NotificationManager notificationManager = getSystemService(NotificationManager.class); notificationManager.createNotificationChannel(channel); } }
Step 2: Set the channel ID for the notification
You have two options for setting the channel ID for the notification. You can either use ContentRecommendation
and use reflection to set the channel ID, or you can use Notification.Builder
.
Option 1: Use createContentRecommendation
and use reflection to set the channel ID
Notification notification = createContentRecommendation(largeIcon, notificationId);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
Log.d(TAG, "SDK version is >= Android O");
try {
Field channel = notification.getClass().getDeclaredField("mChannelId");
channel.setAccessible(true);
channel.set(notification, StringTerms.CHANNEL_ID);
}
catch (Exception e) {
Log.d(TAG, "Can't set ChannelId", e);
}
}
Option 2: Use Notification.Builder
with channel ID
The following code is adapted from the Android Open Source Project on Google Git.
public Notification getNotificationObject(Context context) {
Notification.Builder builder = new Notification.Builder(context, "channelId");
RecommendationExtender recExtender = new RecommendationExtender();
// Encode all the content recommendation data in a Notification object
builder.setCategory(Notification.CATEGORY_RECOMMENDATION);
builder.setContentTitle(mTitle);
builder.setContentText(mText);
builder.setContentInfo(mSourceName);
builder.setLargeIcon(mContentImage);
builder.setSmallIcon(mBadgeIconId);
if (mBackgroundImageUri != null) {
builder.getExtras().putString(Notification.EXTRA_BACKGROUND_IMAGE_URI, mBackgroundImageUri);
}
builder.setColor(mColor);
builder.setGroup(mGroup);
builder.setSortKey(mSortKey);
builder.setProgress(mProgressMax, mProgressAmount, false);
builder.setAutoCancel(mAutoDismiss);
if (mContentIntentData != null) {
PendingIntent contentPending;
if (mContentIntentData.mType == INTENT_TYPE_ACTIVITY) {
contentPending = PendingIntent.getActivity(context, mContentIntentData.mRequestCode,
mContentIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT,
mContentIntentData.mOptions);
}
else if (mContentIntentData.mType == INTENT_TYPE_SERVICE) {
contentPending = PendingIntent.getService(context, mContentIntentData.mRequestCode,
mContentIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT);
}
else { // Default:INTENT_TYPE_BROADCAST{
contentPending = PendingIntent.getBroadcast(context,
mContentIntentData.mRequestCode,
mContentIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT);
}
builder.setContentIntent(contentPending);
}
if (mDismissIntentData != null) {
PendingIntent dismissPending;
if (mDismissIntentData.mType == INTENT_TYPE_ACTIVITY) {
dismissPending = PendingIntent.getActivity(context, mDismissIntentData.mRequestCode,
mDismissIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT,
mDismissIntentData.mOptions);
}
else if (mDismissIntentData.mType == INTENT_TYPE_SERVICE) {
dismissPending = PendingIntent.getService(context, mDismissIntentData.mRequestCode,
mDismissIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT);
}
else { // Default:INTENT_TYPE_BROADCAST{
dismissPending = PendingIntent.getBroadcast(context,
mDismissIntentData.mRequestCode,
mDismissIntentData.mIntent, PendingIntent.FLAG_UPDATE_CURRENT);
}
builder.setDeleteIntent(dismissPending);
}
recExtender.setContentTypes(mContentTypes);
recExtender.setGenres(mContentGenres);
recExtender.setPricingInformation(mPriceType, mPriceValue);
recExtender.setStatus(mStatus);
recExtender.setMaturityRating(mMaturityRating);
recExtender.setRunningTime(mRunningTime);
builder.extend(recExtender);
Notification notif = builder.build();
return notif;
}
For more details, consult the Android documentation on Create and Manage Notification Channels.
Amazon Device Messaging (ADM) compatibility
If your app uses Amazon Device Messaging, you need to update the SDK to avoid crashes on Fire OS 7. In previous releases, ADM used IntentService
to send messages to client applications running in the background. In Fire OS 7, IntentService
is subject to all the background execution limits imposed with Android 8.0 (API level 26). For example, according to Background Service Limitations in the Android documentation:
IntentService
is a service, and is therefore subject to the new restrictions on background services. As a result, many apps that rely onIntentService
do not work properly when targeting Android 8.0 or higher. For this reason, Android Support Library 26.0.0 introduces a newJobIntentService
class, which provides the same functionality asIntentService
but uses jobs instead of services when running on Android 8.0 or higher.
In order for apps to receive ADM messages while running in the background, they must use a JobIntentService
. This newer class uses jobs instead of services when running on Android 8.0 or higher.
ADMMessageHandlerJobBase
is a new class that will use JobIntentService
to deliver messages in the background. You should use this class in place of the old ADMMessageHandlerBase
. When creating an app which interacts with ADM, you should extend ADMMessageHandlerJobBase
in your handler. To follow along with an example, see Implement Handling for Registration and Messages. Additionally, see also Set Up Amazon Device Messaging and Update your App Manifest, which were also updated as part of the release.
You can download the updated ADM SDK here.
Wake lock changes
If a customer hasn't interacted with an app that's in focus and awake within 4 hours, they will receive a “Are you still watching?” prompt and if not acknowledged, they will be taken back home. For more information, see Wake Lock Requirements.
This feature can be turned off in Settings. If the app is a signage app, contact Amazon to be exempted.
Support
If you notice any issues with your app on Fire OS 7, note the issue in the Amazon Fire TV and Fire TV Stick forums.