- Watch Faces for Android Wear
@@ -34,10 +39,10 @@ an activity in the wearable app, an activity on the handheld app, or both. Users
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
+
The digital watch face from the
+WatchFace sample 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.
+response to configuration changes.
@@ -107,7 +112,8 @@ href="{@docRoot}training/wearables/data-layer/index.html">Wearable Data Layer AP
communicate the configuration change to the watch face activity.
For more details, see the DigitalWatchFaceWearableConfigActivity and
-DigitalWatchFaceUtil classes in the WatchFace sample.
+DigitalWatchFaceUtil classes in the
+WatchFace sample.
@@ -141,17 +147,20 @@ href="{@docRoot}training/wearables/data-layer/index.html">Wearable Data Layer AP
communicate the configuration change to the watch face activity.
For more details, see the DigitalWatchFaceCompanionConfigActivity class in the
-WatchFace sample.
+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
+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.
+DigitalWatchFaceService classes in the
+WatchFace sample.
diff --git a/docs/html/training/wearables/watch-faces/information.jd b/docs/html/training/wearables/watch-faces/information.jd
index 41319a10f9d74..ed0cc22dde654 100644
--- a/docs/html/training/wearables/watch-faces/information.jd
+++ b/docs/html/training/wearables/watch-faces/information.jd
@@ -9,6 +9,11 @@ page.title=Showing Information in Watch Faces
- Create a Compelling Experience
- Add Data to Your Watch Face
+Related Samples
+
You should also read
- Watch Faces for Android Wear
@@ -77,10 +82,11 @@ weather.
Figure 2. The calendar watch face.
-The WatchFace sample in the Android SDK demonstrates how to obtain calendar data
-from the user’s profile in the CalendarWatchFaceService class and shows how many
-meetings there are in the following twenty-four hours. This sample is located in the
-android-sdk/samples/android-21/wearable/WatchFace directory.
+The
+WatchFace
+sample demonstrates how to obtain calendar data from the user’s profile in the
+CalendarWatchFaceService class and shows how many
+meetings there are in the following twenty-four hours.
To implement a watch face that incorporates contextual data, follow these steps:
@@ -95,9 +101,10 @@ meetings there are in the following twenty-four hours. This sample is located in
Provide a task to retrieve data
-Create a class inside your CanvasWatchFaceService.Engine implementation that
-extends {@link android.os.AsyncTask} and add the code to retrieve the data you’re interested
-in.
+Create a class inside your
+CanvasWatchFaceService.Engine
+implementation that extends {@link android.os.AsyncTask} and add the code to retrieve the data
+you’re interested in.
The CalendarWatchFaceService class obtains the number of meetings in the next
day as follows:
@@ -130,8 +137,10 @@ private class LoadMeetingsTask extends AsyncTask<Void, Void, Integer> {
}
-The WearableCalendarContract class from the Wearable Support Library provides
-direct access to the user's calendar events from the companion device.
+The
+WearableCalendarContract
+class from the Wearable Support Library provides direct access to the user's calendar events from
+the companion device.
When the task finishes retrieving data, your code invokes a callback method. The following
sections describe how to implement the callback method in detail.
@@ -189,9 +198,12 @@ section.
Redraw your watch face with the updated data
-When the task that retrieves your data finishes, call the invalidate() method
-so the system redraws your watch face. Store your data inside member variables of the
-Engine class so you can access it inside the onDraw() method.
+When the task that retrieves your data finishes, call the
+invalidate()
+method so the system redraws your watch face. Store your data inside member variables of the
+Engine class so you can access it inside the
+onDraw()
+method.
The CalendarWatchFaceService class provides a callback method for the task to
invoke when it finishes retrieving calendar data:
diff --git a/docs/html/training/wearables/watch-faces/issues.jd b/docs/html/training/wearables/watch-faces/issues.jd
index 47c5e8c31f699..2b6172442f97b 100644
--- a/docs/html/training/wearables/watch-faces/issues.jd
+++ b/docs/html/training/wearables/watch-faces/issues.jd
@@ -31,8 +31,11 @@ should adapt to and take advantage of the particular shape of the screen, as des
design guidelines.
Android Wear lets your watch face determine the screen shape at runtime. To detect whether
-the screen is square or round, override the onApplyWindowInsets() method in the
-CanvasWatchFaceService.Engine class as follows:
+the screen is square or round, override the
+onApplyWindowInsets()
+method in the
+CanvasWatchFaceService.Engine
+class as follows:
private class Engine extends CanvasWatchFaceService.Engine {
@@ -75,7 +78,9 @@ the notification card is present.
down the watch face to fit inside the portion of the screen not covered by the peek card. Digital
watch faces that display the time in the area of the screen not covered by peek cards do not
usually require adjustments. To determine the free space above the peek card so you can adapt
-your watch face, use the WatchFaceService.getPeekCardPosition() method.
+your watch face, use the
+WatchFaceService.Engine.getPeekCardPosition()
+method.
In ambient mode, peek cards have a transparent background. If your watch face contains details
near the card in ambient mode, consider drawing a black rectangle over them to ensure that users
@@ -93,16 +98,21 @@ can read the contents of the card.
To ensure that the system indicators remain visible, you can configure their position on the
-screen and whether they need background protection when you create a WatchFaceStyle
+screen and whether they need background protection when you create a
+WatchFaceStyle
instance:
Move Expensive Operations Outside the Drawing Method
-
The system calls the Engine.onDraw() method every time it redraws your watch
-face, so you should only include operations that are strictly required to update the watch
-face inside this method to improve performance.
+
The system calls the
+Engine.onDraw()
+method every time it redraws your watch face, so you should only include operations that are
+strictly required to update the watch face inside this method to improve performance.
-
When possible, avoid performing these operations inside the onDraw() method:
+
When possible, avoid performing these operations inside the
+Engine.onDraw()
+method:
- Loading images and other resources.
@@ -118,13 +123,17 @@ face inside this method to improve performance.
- Performing computations whose result does not change between frames.
-
You can usually perform these operations in the Engine.onCreate() method instead.
+
You can usually perform these operations in the
+Engine.onCreate()
+method instead.
You can resize images ahead of time in the {@link
android.service.wallpaper.WallpaperService.Engine#onSurfaceChanged(android.view.SurfaceHolder, int, int, int)
Engine.onSurfaceChanged()} method, which provides you with the size of the canvas.
To analyze the performance of your watch face, use the Android Device Monitor. In particular,
-ensure that the execution time for your Engine.onDraw() implementation is short and
+ensure that the execution time for your
+Engine.onDraw()
+implementation is short and
consistent across invocations. For more information, see
Using DDMS.
diff --git a/docs/html/training/wearables/watch-faces/service.jd b/docs/html/training/wearables/watch-faces/service.jd
index 35366c5f83ebc..578e8c01474ad 100644
--- a/docs/html/training/wearables/watch-faces/service.jd
+++ b/docs/html/training/wearables/watch-faces/service.jd
@@ -10,6 +10,11 @@ page.title=Building a Watch Face Service
Implement the Service Callback Methods
Register the Service Implementation
+
Related Samples
+
You should also read
- Watch Faces for Android Wear
@@ -64,7 +69,9 @@ Project.
Dependencies
-The Wearable Support Library provides the necessary classes that you extend to create watch
+
The
+Wearable Support Library
+provides the necessary classes that you extend to create watch
face implementations. The Google Play services client libraries (play-services and
play-services-wearable) are required to sync data items between the companion device
and the wearable with the Wearable
@@ -116,10 +123,15 @@ or when an important event occurs (like switching to ambient mode or receiving a
notification). The service implementation then draws the watch face on the screen using the
updated time and any other relevant data.
-To implement a watch face, you extend the CanvasWatchFaceService
-and CanvasWatchFaceService.Engine classes, and then you override the callback methods
-in the CanvasWatchFaceService.Engine class. These classes are included in the
-Wearable Support Library.
+To implement a watch face, you extend the
+CanvasWatchFaceService
+and
+CanvasWatchFaceService.Engine
+classes, and then you override the callback methods in the
+CanvasWatchFaceService.Engine
+class. These classes are included in the
+Wearable Support Library.
+
The following snippet outlines the key methods you need to implement:
@@ -173,20 +185,21 @@ public class AnalogWatchFaceService extends CanvasWatchFaceService {
}
-Note: The WatchFace sample in the Android SDK
-demonstrates how to implement analog and digital watch faces extending the
-CanvasWatchFaceService class. This sample is located in the
-android-sdk/samples/android-21/wearable/WatchFace directory.
-
-The CanvasWatchFaceService class provides an invalidate mechanism similar to
+
The
+CanvasWatchFaceService
+class provides an invalidate mechanism similar to
the {@link android.view.View#invalidate View.invalidate()} method. You can call the
-invalidate() method throughout your implementation when you want the system to
-redraw the watch face. You can only use the invalidate() method in the main UI
-thread. To invalidate the canvas from another thread, call the postInvalidate()
+invalidate()
+method throughout your implementation when
+you want the system to redraw the watch face. You can only use the
+invalidate()
+method in the main UI thread. To invalidate the canvas from another thread, call the
+postInvalidate()
method.
For more information about implementing the methods in the
-CanvasWatchFaceService.Engine class, see CanvasWatchFaceService.Engine
+class, see Drawing Watch Faces.