Android Wear 2.0 updates the visual style and interaction paradigm of notifications as well as introduces expanded notifications, which provide substantial additional content and actions in an app-like experience.
The visual and interaction changes make it much easier for users to read and interact with notifications from your app. Expanded notifications enable you to deliver Wear users an app-like experience even if you haven't built an Android Wear app.
Note: When developing for Wear 2.0, ensure that you have the latest version of the Android Wear app on your phone.
Notifications receive important visual updates in Wear 2.0, with material design visual changes.
Figure 1. Comparison of the same notification in Android Wear 1.x and 2.0.
Some of the visual updates include:
- Updated touch targets of a notification:
contentIntentis set or if the notification is bridged from a paired phone, then tapping the notification opens an expanded notification. If the notification is generated locally by a Wear app and if a
contentIntentis set, tapping the notification fires the
- Dark background color:
If you have notifications that are bridged to wearables, you need to be careful
with regards to using color for the notifications. Since a bridged
notification needs to support both light (Wear 1.x) and dark (Wear 2.0)
backgrounds, it is unlikely that any colors will work well on both.
DisplayIntentnotifications render with both light and dark backgrounds as well, and need to be checked for the same reason. We recommended that you don't set color for bridged notifications. When Wear apps post local notifications, you can work around this by checking the API level of the device they're running on and using an appropriate color for Wear 1.x and a different color for Wear 2.0.
- Updated horizontal swipe gesture on a notification: To dismiss a notification in Wear 2.0, the user swipes horizontally in either direction. So if your notification instructs the user to swipe left or right, you must update the text of your notification.
Wear 2.0 now supports inline action, which allows users to take actions on a notification from within the notification stream card. On Wear, the inline action appears as an additional button displayed at the bottom of the notification.
Inline actions are optional but recommended for cases in which users are likely to take an action on a notification after viewing the contents in the notification stream card (without going to the expanded notification). Examples of good use cases for inline action on a notification include: replying to a text message, stopping a fitness activity, and archiving an email message.
A notification can provide only one inline action.
To display the inline action as an additional button in the notification, set
method to true. When a user taps the inline action, the system invokes
the intent that you specified in the notification action.
Adding an inline action
The following code example shows how to create a notification with an inline reply action:
- Create an instance of
RemoteInput.Builderthat you can add to your notification action. This class's constructor accepts a string that the system uses as the key for the text input. Later, your app uses that key to retrieve the text of the input.
String choices = context.getResources().getStringArray(R.array.notification_reply_choices); choices = WearUtil.addEmojisToCannedResponse(choices); RemoteInput remoteInput = new RemoteInput.Builder(Intent.EXTRA_TEXT) .setLabel(context.getString(R.string.notification_prompt_reply)) .setChoices(choices) .build();
addRemoteInput()method to attach the
RemoteInputobject to an action.
NotificationCompat.Action.Builder actionBuilder = new NotificationCompat.Action.Builder( R.drawable.ic_full_reply, R.string.notification_reply, replyPendingIntent); actionBuilder.addRemoteInput(remoteInput); actionBuilder.setAllowGeneratedReplies(true);
Add a hint to display the reply action inline, and use the
addActionmethod to add this action to the notification.
// Android Wear 2.0 requires a hint to display the reply action inline. Action.WearableExtender actionExtender = new Action.WearableExtender() .setHintLaunchesActivity(true) .setHintDisplayActionInline(true); wearableExtender.addAction(actionBuilder.extend(actionExtender).build());
Android Wear 2.0 introduces expanded notifications, which provide substantial additional content and actions for each notification.
When you specify additional content pages and actions for a notification, those are available to the user within the expanded notification. Each expanded notification follows Material Design for Android Wear, so the user gets an app-like experience.
The user can view the expanded notification by tapping on a notification when either of the following is true:
- The notification is generated by an app on the paired phone and bridged to Wear.
- The notification does not have a
Best practices for expanded notifications
To decide when to use expanded notifications, follow these guidelines:
- All notifications bridged from the paired phone to the Wear device will use expanded notifications.
- If a notification is generated by an app running locally on Wear 2.0,
make the touch target of your notification launch
within your app by calling
setContentIntent(). We recommend that you do not use expanded notifications for notifications generated by an app running locally on Wear 2.0.
Adding expanded notifications
Expanded Notifications allow you to include additional content and actions for a notification. You choose the level of detail that your app's notifications will provide; however be judicious with the amount of detail you include in a notification.
Adding additional contentTo show additional content in your expanded notification, see Adding Pages to a Notification.
Additional content pages are stacked vertically in the expanded notification
and appear in the order they were added.
These additional content pages can optionally use a style such as
Primary actionThe expanded notification will contain one primary action, which is the first action in the notification unless a different action is specified using
If you have a chat messaging app, your notifications should use
which is new in Android 7.0. Wear 2.0 uses the chat messages included in a
to provide a rich chat app-like experience in the expanded notification.
Wear 2.0 also introduces Smart Reply for
Smart Reply provides the user with contextually relevant, touchable choices in
the expanded notification and in
RemoteInput. These augment the fixed
list of choices that the developer provides in
Smart Reply provides users with a fast (single tap), discreet (no speaking aloud), private (messages received by a user never leave the watch), and reliable (no internet connection needed) way to respond to chat messages.
Smart Reply responses are generated by an entirely on-watch machine learning model using the context provided by the MessagingStyle notification. No user notification data is sent to Google servers to generate Smart Reply responses.
To enable Smart Reply for your notification action, you need to do the following:
- Call the method
setAllowGeneratedReplies(true)for the notification action.
- Ensure that the notification action has a
RemoteInput(where the responses will reside).
The following example shows how to create a MessagingStyle notification with Smart Reply responses.
// Create an intent for the reply action Intent replyIntent = new Intent(this, ReplyActivity.class); PendingIntent replyPendingIntent = PendingIntent.getActivity(this, 0, replyIntent, PendingIntent.FLAG_UPDATE_CURRENT); // Create the reply action and add the remote input NotificationCompat.Action action = new NotificationCompat.Action.Builder(R.drawable.ic_reply_icon, getString(R.string.label), replyPendingIntent) .addRemoteInput(remoteInput) // 1) allow generated replies .setAllowGeneratedReplies(true) .build(); Notification noti = new NotificationCompat.Builder() .setContentTitle(messages.length + " new messages with " + sender.toString()) .setContentText(subject) .setSmallIcon(R.drawable.new_message) .setLargeIcon(aBitmap) // 2) set the style to MessagingStyle .setStyle(new NotificationCompat.MessagingStyle(resources.getString(R.string.reply_name)) .addMessage(messages.getText(), messages.getTime(), messages.getSender()) .addMessage(messages.getText(), messages.getTime(), messages.getSender())) // 3) add an action with RemoteInput .extend(new WearableExtender().addAction(action)).build();
Adding images to a MessagingStyle notification
You can add images to a notification message by setting the appropriate MIME
type and placing the URI to the image in
Here is the code snippet to set data of type image in a notification:
NotificationCompat.MessagingStyle.Message message = new Message("sticker", 1, "Jeff") .setData("image/png", stickerUri); NotificationCompat notification = new NotificationCompat.Builder() .setStyle(new NotificationComapt.MessagingStyle("Me") .addMessage(message) .build());
In the above code snippet the variable
stickerUri is a Uri that
points to a publicly-accessible location, as described here