Wear OS by Google developer preview

Posted by Hoi Lam, Lead Developer Advocate, Wear OS by Google

Today we launched the Wear OS by Google developer preview and brought Android P platform features to wearables. The developer preview includes updated system images on the official Android Emulator and a downloadable system image for the Huawei Watch 2 Bluetooth or Huawei Watch 2 Classic Bluetooth. This initial release is intended for developers only and is not for daily or consumer use. Therefore, it is only available via manual download and flash. Please refer to the release notes for known issues before downloading and flashing your device.

In this release, we would like to highlight the following features that developers should pay attention to:

  • Restriction related to non-SDK methods and fields: To improve app compatibility, Android P has started the process of restricting access to non-SDK methods and fields. Developers should make plans to migrate away from these. If there is no public equivalent for your use case, please let us know.
  • Dark UI system theme: To enhance glanceability, Wear OS has switched to a UI theme with a darker / black background for the notifications stream and system launcher since the start of the year. This is now also the default for the system theme and should improve the glanceability for wear apps. Developers should check the accessibility of their app’s UI after this change.
  • Limited background activity: To improve power, apps will no longer be allowed to run in the background unless the watch is on the charger. Developers should note that Wear OS is going further with Android’s app standby feature than some other form factors. Exceptions to this include watch faces and complications that the user currently has selected. This feature will be rolled out gradually in the developer preview, so you may not see it immediately on your device, but should build your apps accordingly by removing background services.
  • Turning off radios when off body: To improve power, bluetooth, WiFi, and cellular radios will be turned off when the watch is detected to be off body for an extended period of time. Again, this feature will be rolled out gradually so you may not initially see it on your device. If this feature causes challenges in your development process, you can disable the feature via adb; please follow the instructions in the release notes.
  • WiFi off when BT is disconnected: To improve power, the device will no longer automatically connect to wifi when disconnected from bluetooth. Exceptions include if an app is requesting a high bandwidth network or if the watch is on the charger. This feature will be rolled out gradually so you may not initially see it on your device.

Please give us your feedback

We expect to provide several updates to this preview before the final production release. Please submit any bugs you find via the Wear OS by Google issue tracker. The earlier you submit them, the higher the likelihood that we can include the fixes in the final release.

Android Things Developer Preview 6

Posted by Wayne Piekarski,
Developer Advocate for IoT

The next release of Android Things Developer Preview 6 (DP6) is here with lots
of new features and bug fixes. Android Things is Google’s platform that enables
Android Developers to create Internet of Things (IoT) devices with support for
powerful applications such as video and audio processing and on-board machine
learning with TensorFlow. For the specifics on what is new, visit the release
notes
. Here are a few of the highlights of what is in DP6.

IoT launcher

DP6 includes a new IoT launcher that allows the user to see the current state of
the device and change settings using a touch screen or USB input devices.
Settings such as configuring the WiFi, finding the build ID, and checking for
updates is now something that can be done interactively, making it even easier
to get started. This launcher is visible when no other developer-provided IOT_LAUNCHER
Activity is present.

Graphics acceleration defaults

Android Things uses the open-source SwiftShader library, a
CPU-based implementation of the OpenGL ES APIs. This enables common OpenGL
support across all platforms, even those with no GPU hardware. However, many
simple 2D UIs render faster if the drawing is done directly to the framebuffer
and OpenGL emulation is not used. In DP6, OpenGL rendering is disabled by
default to ensure that most apps run with the fastest UI possible. If you need
OpenGL support for 3D rendering, WebView, or TextureView, then explicitly enable
it in your AndroidManifest.xml according to the documentation:

<activity

    ...
    android:hardwareAccelerated="true">

API 27 and Google Play Services

DP6 is now based on the latest Android 8.1 developer preview, with API level 27.
Most of the standard Android samples now work on DP6. For example, the Camera2Basic
sample using the Camera2 API and TextureView now works on both NXP and Raspberry
Pi based devices (with the hardwareAccelerated flag set to true). Google Play
Services has been updated to support SDK version 11.6, supporting all the latest
features
.

Command-line flashing tool

We heard from developers that flashing and configuring a board using fastboot
can be tedious, so the Android Things
Console
now brings a new and simpler way of flashing device images. Instead
of using fastboot and adb commands manually, a new interactive command-line
android-things-setup-utility
is now provided. This tool makes it much easier to get started with Android
Things, and automates the download and flashing process.

Android Things Console updates

DP6 introduces the new partition scheme that will be used for the upcoming
production release. Due to the new partition layout, the over-the-air update
(OTA) system cannot update existing DP5.1 or earlier devices. Developers will
need to go to the Android
Things Console
, and download and flash a new DP6 build. The Console UI has
also been changed for DP6 features, and will only allow you to create new builds
based on DP6. If you have any older existing builds, they are still available
for download but will not support OTA updates. Developers are encouraged to move
all work to DP6.

GPIO pin naming

The interactive IoT launcher shown at boot now includes an I/O pinout section
where you can discover the labels of all the pins. The pin naming used by the
i.MX7 has been changed, and you should update your code to use this new naming
convention. See the i.MX7
documentation
for the complete list of pin names.

Settings and Device Update APIs

New APIs have been added to Android Things that control the configuration
of the local device and device updates. UpdateManager
gives developers control over when updates and reboots can be performed,
ensuring the device is available for the user when needed. DeviceManager
controls factory reset, reboot, and device locales. APIs are also provided for
settings such as ScreenManager
to control the screen, and TimeManager
to control the clock and time zone.

Peripheral command-line tool

We now provide a command-line tool pio
that gives developers access to the Peripheral API via the adb shell. Developers
can interactively test GPIO, PWM, UART, I2C, SPI, and future interfaces from an
adb shell, which is useful for debugging and automated testing.

Feedback

DP6 includes significant changes and improvements to the platform. Please send
us your feedback by filing bug
reports
and feature
requests
, as well as asking any questions on Stack
Overflow
. To start using DP6, use the Android Things Console to
download system images and flash existing devices, or use the android-things-setup-utility.
More information about the changes are available in the release
notes
. You can also join Google’s IoT
Developers Community
on Google+, a great resource to get updates and discuss
ideas. Also, we have our new hackster.io
community
, where everyone can share the amazing projects they have built. We
look forward to seeing what you build with Android Things!