Providing Configuration Activities

When users install a handheld app that contains a wearable app with watch faces, these watch faces become available in the Android Wear companion app on the companion device and in the watch face picker on the wearable. Users can choose the active watch face for their wearable device by selecting it on the companion app or using the watch face picker on the wearable device.

Some watch faces support configuration parameters to let users customize how the watch face looks and behaves. For example, some watch faces let users pick a custom background color, and watch faces that tell time for two different time zones can let users select which time zones they are interested in.

Watch faces that support configuration parameters can let users customize a watch face using an activity in the wearable app, an activity on the handheld app, or both. Users can start the wearable configuration activity on the wearable device, and they can start the companion configuration activity from the Android Wear companion app.

The digital watch face from the WatchFace sample in the Android SDK demonstrates how to implement handheld and wearable configuration activities and how to update a watch face in response to configuration changes. This sample is located in the android-sdk/samples/android-21/wearable/WatchFace directory.

Specify an Intent for Configuration Activities

If your watch face includes configuration activities, add the following metadata entries to the service declaration in the manifest file of the wearable app:

<service
    android:name=".DigitalWatchFaceService" ... />
    <!-- companion configuration activity -->
    <meta-data
        android:name=
           "com.google.android.wearable.watchface.companionConfigurationAction"
        android:value=
           "com.example.android.wearable.watchface.CONFIG_DIGITAL" />
    <!-- wearable configuration activity -->
    <meta-data
        android:name=
           "com.google.android.wearable.watchface.wearableConfigurationAction"
        android:value=
           "com.example.android.wearable.watchface.CONFIG_DIGITAL" />
    ...
</service>

Provide values for these entries that are preceded by the package name of your app. Configuration activities register intent filters for this intent, and the system fires this intent when users want to configure your watch face.

If your watch face only includes a companion or a wearable configuration activity, you only need to include the corresponding metadata entry from the example above.

Create a Wearable Configuration Activity

Wearable configuration activities provide a limited set of customization choices for a watch face, because complex menus are hard to navigate on smaller screens. Your wearable configuration activity should provide binary choices and just a few selections to customize the main aspects of your watch face.

To create a wearable configuration activity, add a new activity to your wearable app module and declare the following intent filter in the manifest file of the wearable app:

<activity
    android:name=".DigitalWatchFaceWearableConfigActivity"
    android:label="@string/digital_config_name">
    <intent-filter>
        <action android:name=
            "com.example.android.wearable.watchface.CONFIG_DIGITAL" />
        <category android:name=
       "com.google.android.wearable.watchface.category.WEARABLE_CONFIGURATION" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

The name of the action in this intent filter must match the intent name you defined in Specify an Intent for Configuration Activities.

In your configuration activity, build a simple UI that provides selections for users to customize your watch face. When users make a selection, use the Wearable Data Layer API to communicate the configuration change to the watch face activity.

For more details, see the DigitalWatchFaceWearableConfigActivity and DigitalWatchFaceUtil classes in the WatchFace sample.

Create a Companion Configuration Activity

Companion configuration activities give users access to the full set of configuration choices for a watch face, because it is easier to interact with complex menus on the larger screen of a handheld device. For example, a configuration activity on a handheld device enables you to present users with elaborate color pickers to select the background color of a watch face.

To create a companion configuration activity, add a new activity to your handheld app module and declare the same intent filter for this activity as the one in Create a Wearable Configuration Activity.

In your configuration activity, build a UI that provides options to customize all the configurable elements of your watch face. When users make a selection, use the Wearable Data Layer API to communicate the configuration change to the watch face activity.

For more details, see the DigitalWatchFaceCompanionConfigActivity class in the WatchFace sample.

Create a Listener Service in the Wearable App

To receive updated configuration parameters from the configuration activities, create a service that implements the WearableListenerService interface from the Wearable Data Layer API in your wearable app. Your watch face implementation can redraw the watch face when the configuration parameters change.

For more details, see the DigitalWatchFaceConfigListenerService and DigitalWatchFaceService classes in the WatchFace sample.