Android Wear 2.0 Developer Preview 3: Play Store and More

Today we’re launching the third developer preview of Android Wear 2.0 with a big new addition: Google Play on Android Wear. The Play Store app makes it easy for users to find and install apps directly on the watch, helping developers like you reach more users.

Play Store features

With Play Store for Android Wear, users can browse recommended apps in the home view and search for apps using voice, keyboard, handwriting, and recommended queries, so they can find apps more easily. Users can switch between multiple accounts, be part of alpha and beta tests, and update or uninstall apps in the “My apps” view on their watch, so they can manage apps more easily. Perhaps the coolest feature: If users want an app on their watch but not on their phone, they can install only the watch app. In fact, in Android Wear 2.0, phone apps are no longer necessary. You can now build and publish watch-only apps for users to discover on Google Play.

Why an on-watch store?

We asked developers like you what you wanted most out of Android Wear, and you told us you wanted to make it easier for users to discover apps. So we ran studies with users to find out where they expected and wanted to discover apps––and they repeatedly looked for and asked for a way to discover apps right on the watch itself. Along with improvements to app discovery on the phone and web, the Play Store on the watch helps users find apps right where they need them.

Publish your apps

To make your apps available on Play Store for Android Wear, just follow these steps. You’ll need to make sure your Android Wear 2.0 apps set minSdkVersion to 24 or higher, use the runtime permissions model, and are uploaded via multi-APK using the Play Developer Console. If your app supports Android Wear 1.0, the developer guide also covers the use of product flavors in Gradle.

Download the New Android Wear companion app

To set up Developer Preview 3, you’ll need to install a beta version of the Android Wear app on your phone, flash your watch to the latest preview release, and use the phone app to add a Google Account to your watch. These steps are detailed in Download and Test with a Device. If you don’t have a watch to test on, you can use the emulator as well.

Other additions in Developer Preview 3

Developer Preview 3 also includes:

• Complications improvements: Starting with Developer Preview 3, watch face developers will need to request RECEIVE_COMPLICATION_DATA permission before the watch face can receive complication data. We have added ComplicationHelperActivity to make this easier. In addition, watch face developers can now set default complications, including a selection of system data complications which do not require special permission (e.g. battery level and step count), as well as data providers that have whitelisted the watch face. Lastly, there are behavior changes related to ComplicationData to 1) help better differentiate various scenarios leading to “empty data” and 2) ease development by returning a default value for fields not supported by a complication type instead of throwing a runtime exception.
• New WearableRecyclerView: This new UI component helps developers display and manipulate vertical lists of items while optimizing for round displays.
• Inline Action for Notifications: A new API makes it easy to take action on a notification right from the stream. Developers can specify which action is displayed inline at the bottom of the notification by calling setHintDisplayActionInline:

  NotificationCompat.Action replyAction =
      new NotificationCompat.Action.Builder(R.drawable.ic_message_white_24dp,
              "Reply", replyPendingIntent)
              .addRemoteInput(remoteInput)
              .extend(new NotificationCompat.Action.WearableExtender()
                      .setHintDisplayActionInline(true))
              .build(); 

• Smart Reply: Android Wear now generates Smart Reply responses for MessagingStyle notifications. Smart Reply responses are generated by an entirely on-watch machine learning model using the context provided by theMessagingStyle notification, and no data is uploaded to the cloud to generate the responses.
• And much more: Read about the complete list of changes in the Android Wear developer preview release notes.
  
  TimelineWe’ve gotten tons of great feedback from the developer community about Android Wear 2.0––thank you! We’ve decided to continue the preview program into early 2017, at which point the first watches will receive Android Wear 2.0. Please keep the feedback coming by filing bugs or posting in our Android Wear Developers community, and stay tuned for Android Wear Developer Preview 4.

Extending Web Technology with Android

Paper Planes started as a simple thought - “What if you could throw a paper plane from one screen to another?”

The heart of our concept was to bring people together from all over the world, using the power of the web - an instant connection to one another. Modern web technology, specifically JavaScript and WebGL, powered the experience on every screen.

Paper Planes was initially featured at Google I/O 2016, connecting attendees and outside viewers for 30 minutes preceding the keynote. For the public launch on International Peace Day 2016, we created an Android Experiment, which is also featured on Google Play, to augment the existing web technology with native Android Nougat features such as rich notifications when a plane is caught elsewhere in the world.

Introduction

Users create and fold their own plane while adding a stamp that is pre-filled with their location. A simple throwing gesture launches the plane into the virtual world. Users visiting the desktop website would see their planes flying into the screen.

Later, users can check back and see where their planes have been caught around the world. Each stamp on the plane reads like a passport, and a 3D Earth highlights flightpath and distance travelled.

In addition to making their own planes, users can gesture their phone like a net to catch a plane that has been thrown from elsewhere and pinch to open it, revealing where it has visited. Then they can add their own stamp, and throw it back into the flock.

WebView

We developed Paper Planes to work across devices ranging from the 50-foot screen on stage at Google I/O to desktop and mobile using the latest in web technology.

WebGL

From the stylized low-poly Earth to the flocking planes, WebGL is used to render the 3D elements that power the experience. We wrote custom GLSL shaders to light the Earth and morph targets to animate the paper as the user pinches to open or close.

WebSockets

When a user “throws” a plane a message is sent over websockets to the back-end servers where it is relayed to all desktop computers to visualize the plane taking off.

WebWorkers

The plane flocking simulation is calculated across multiple threads using WebWorkers that calculate the position of each plane and relay that information back to the main thread to be rendered by WebGL.

To create an experience that works great across platforms, we extended the web with native Android code. This enabled us to utilize the deep integration of Chromium within Android to make the view layer of the application with the web code that already existed, while adding deeper integration with the OS such as rich notifications and background services.

If you’re interested in learning more about how to bridge WebView and Java code, check out this GitHub repo for a tutorial.

Notifications

Firebase Cloud Messaging (FCM) was used to send push notifications to the Android app. When a user’s plane has been caught and thrown by someone else, a notification showing how many cities and miles it has travelled is sent to the device of the plane’s creator via FCM. Outgoing notifications are managed to ensure they are not sent too frequently to a device.

Background Service

We implemented a background service to run once a day which checks against local storage to determine when a user last visited the app. If the user hasn’t visited in over two weeks, the app sends a notification to invite the user back into the app to create a new plane.

The Communication Network

Our application runs on a network of servers on Google Cloud Platform. We used built-in geocoding headers to get approximate geographic locations for stamps and Socket.IO to connect all devices over WebSockets.

Users connect to the server nearest them, which relays messages to a single main server as well as to any desktop computers viewing the experience in that region.

Moving forward

This approach worked extremely well for us, enabling an experience that was smooth and captivating across platforms and form factors, connecting people from all over the world. Extending the web with native capabilities has proven to be a valuable avenue to deliver high quality experiences going forward. You can learn even more on the Android Experimentswebsite.

Android Studio 2.2

Android Studio 2.2 is available to download today. Previewed at Google I/O 2016, Android Studio 2.2 is the latest release of our IDE used by millions of Android developers around the world.

Packed with enhancements, this release has three major themes: speed, smarts, and Android platform support. Develop faster with features such as the new Layout Editor, which makes creating an app user interface quick and intuitive. Develop smarter with our new APK analyzer, enhanced Layout Inspector, expanded code analysis, IntelliJ’s 2016.1.3 features and much more. Lastly, as the official IDE for Android app development, Android Studio 2.2 includes support for all the latest developer features in Android 7.0 Nougat, like code completion to help you add Android platform features like Multi-Window support, Quick Settings API, or the redesigned Notifications, and of course, the built-in Android Emulator to test them all out.

In this release, we evolved the Android Frameworks and the IDE together to create the Constraint Layout. This powerful new layout manager helps you design large and complex layouts in a flat and streamlined hierarchy. The ConstraintLayoutintegrates into your app like a standard Android support library, and was built in parallel with the new Layout Editor.

Android Studio 2.2 includes 20+ new features across every major phase of the development process: design, develop, build, & test. From designing UIs with the new ConstraintLayout, to developing C++ code with the Android NDK, to building with the latest Jack compliers, to creating Espresso test cases for your app, Android Studio 2.2 is the update you do not want to miss. Here’s more detail on some of the top highlights:

Design

• Layout Editor: Creating Android app user interfaces is now easier with the new user interface designer. Quickly construct the structure of your app UI with the new blueprint mode and adjust the visual attributes of each widget with new properties panel. Learn more.

Layout Editor

• Constraint Layout: This new layout is a flexible layout manager for your app that allows you to create dynamic user interfaces without nesting multiple layouts. It is backwards compatible all the way back to Android API level 9 (Gingerbread). ConstraintLayout works best with the new Layout Editor in Android Studio 2.2. Learn more.

ConstraintLayout

Develop

• Improved C++ Support: You can now use CMake or ndk-build to compile your C++ projects from Gradle. Migrating projects from CMake build systems to Android Studio is now seamless. You will also find C++ support in the new project wizard in Android Studio, plus a number of bug fixes to the C++ edit and debug experience. Learn more.

C++ Code Editing & CMake Support

• Samples Browser: Referencing Android sample code is now even easier with Android Studio 2.2. Within the code editor window, find occurrences of your app code in Google Android sample code to help jump start your app development. Learn more.

Sample Code Menu

Build

• Instant Run Improvements: Introduced in Android Studio 2.0, Instant Run is our major, long-term investment to make Android development as fast and lightweight. Since launch, it has significantly improved the edit, build, run iteration cycles for many developers. In this release, we have made many stability and reliability improvements to Instant Run. If you have previously disabled Instant Run, we encourage you to re-enable it and let us know if you come across further issues. (Settings → Build, Execution, Deployment → Instant Run [Windows/Linux] , Preferences → Build, Execution, Deployment → Instant Run [OS X]). For details on the fixes that we have made, see the Android Studio 2.2 release notes.

Enable Instant Run

• APK Analyzer: Easily inspect the contents of your APKs to understand the size contribution of each component. This feature can be helpful when debugging multi-dex issues. Plus, with the APK Analyzer you can compare two versions of an APK. Learn more.

APK Analyzer

• Build cache (Experimental): We are continuing our investments to improve build speeds with the introduction of a new experimental build cache that will help reduce both full and incremental build times. Just add android.enableBuildCache=true to your gradle.properties file. Learn more.

Build Cache Setting

Test

• Virtual Sensors in the Android Emulator: The Android Emulator now includes a new set of virtual sensors controls. With the new UI controls, you can now test Android Sensors such as Accelerometer, Ambient Temperature, Magnetometer and more. Learn more.

Android Emulator Virtual Sensors

• Espresso Test Recorder (Beta): The Espresso Test Recorder lets you easily create UI tests by recording interactions with your app; it then outputs the UI test code for you. You record your interactions with a device and add assertions to verify UI elements in particular snapshots of your app. Espresso Test Recorder then takes the saved recording and automatically generates a corresponding UI test. You can run the test locally, on your continuous integration server, or using Firebase Test Lab for Android. Learn more.

Espresso Test Recorder

• GPU Debugger (Beta): The GPU Debugger is now in Beta. You can now capture a stream of OpenGL ES commands on your Android device and then replay it from inside Android Studio for analysis. You can also fully inspect the GPU state of any given OpenGL ES command to better understand and debug your graphical output.Lean more.

GPU Debugger

To recap, Android Studio 2.2 includes these major features and more:

Design Layout Editor Constraint Layout Layout Inspector (Experimental) PSD File Support in Vector Asset Studio Develop Firebase Plugin Updated Code Analysis & Lint checks Enhanced accessibility support Improved C++ Support Edit & Debugging IntelliJ 2016.1.3 platform update Samples Browser Improved Font Rendering

Build Jack Compiler Improvements Java 8 Language Support C++ ndk-build or CMake Merged Manifest Viewer Build cache (Experimental) OpenJDK Support Instant Run Improvements Test Espresso Test Recorder (Beta) APK Analyzer GPU Debugger (Beta) Virtual Sensors in the Android Emulator

Learn more about Android Studio 2.2 by reviewing the release notes and the preview blog post.

Getting Started

Download

If you are using a previous version of Android Studio, you can check for updates on the Stable channel from the navigation menu (Help → Check for Update [Windows/Linux] , Android Studio → Check for Updates [OS X]). You can also download Android Studio 2.2 from the official download page. To take advantage of all the new features and improvements in Android Studio, you should also update to the Android Gradle plugin version to 2.2.0 in your current app project.

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