Build Mobile App Services with Google Cloud Tools for Android Studio v1.0

Posted by Chris Sells, Product Manager, Cloud Tools for Android Studio

Cloud Tools for Android Studio allows you to simultaneously build the service- and client-side of your mobile app. Earlier this month, we announced the release of Android Studio 1.0 that showed just how much raw functionality there is available for Android app developers. However, the client isn’t the whole picture, as most mobile apps also need one or more web services. It was for this reason that the Cloud Tools for Android Studio were created.

Cloud Tools put the power of Google App Engine in the same IDE alongside of your mobile client, giving you all the same Java language tools for both sides of your app, as well as making it far easier for you to keep them in sync as each of them changes.

Getting Started

To get started with Cloud Tools for Android Studio, add a New Module to your Android Studio project, choose Google Cloud Module and you’ll have three choices:

You can add three Google Cloud module types to your Android Studio project

The Java Servlet Module gives you a plain servlet class for you to implement as you see fit. If you’d like help building your REST endpoints with declarative routing and HTTP verbs and automatic Java object serialization to and from JSON, then you’ll want the Java Endpoints Module. If you want the power of endpoints, along with the ability to send notifications from your server to your clients, then choose Backend with Google Cloud Messaging.

Once you’re done, you’ll have your service code right next to your client code:

You can build your mobile app’s client and service code together in a single project

Not only does this make it very convenient to build and test your entire end-to-end, but we also dropped a little extra something into your app’s build.gradle file:

The android-endpoints configuration build step in your build.gradle file creates a client-side library for your server-side endpoint

The updated Gradle file will now create a library for use in your app’s client code that changes when your service API changes. This library lets you call into your service from your client and provides full code completion as you do:

The client-side endpoint library provides code completion and documentation

Instead of writing the code to create HTTP requests by hand, you can make calls via the library in a typesafe manner and the marshalling from JSON to Java will be handled for you, just like on the server-side (but in reverse, of course).

Endpoints Error Detection

Meanwhile, back on the server-side, as you make changes to your endpoints, we’re watching to make sure that they’re in good working order even before you compile by checking the attributes as you type:

Cloud Tools will detect errors in your endpoint attributes

Here, Cloud Tools have found a duplicate name in the ApiMethod attribute, which is easy to do if you’re creating a new method from an existing method.

Creating an Endpoint from an Objectify Entity

If, as part of your endpoint implementation, you decide to take advantage of the popular Objectify library, you’ll find that Cloud Tools provides special support for you. When you right-click (or control-click on the Mac) on a file containing an Objectify entity class, you’ll get the Generate Cloud Endpoint from Java class option:

The generate Cloud Endpoint from Java class option will create a CRUD endpoint for you

If you’re running this option on a Java class that isn’t built with Objectify, then you’re going to get an endpoint with empty methods for get and insert operations that you can implement as appropriate. However, if you do this with an Objectify entity, you’ll get a fully implemented endpoint:

Cloud Tools has built-in support for generating Objectify-based cloud endpoint implementations

Using your Cloud Endpoint

As an Android developer, you’re used to deploying your client first in the emulator and then into a local device. Likewise, with the service, you’ll want to test first to your local machine and then, when you’re ready, deploy into a Google App Engine project. You can run your service app locally by simply choosing it from the Configurations menu dropdown on the toolbar and pressing the Run button:

The Configurations menu in the toolbar lets you launch your service for testing

This will build and execute your service on http://localhost:8080/ (by default) so that you can test against it with your Android app running in the emulator. Once you’re ready to deploy to Google Cloud Platform, you can do so by selecting the Deploy Module to App Engine option from the Build menu, where you’ll be able to choose the source module you want to deploy, log into your Google account and pick the target project to which you’d like to deploy:

The Deploy to App Engine dialog will use your Google credentials to enumerate your projects for you

Cloud Tools beta required some extra copying and pasting to get the Google login to work, but all of that’s gone now in this release.

What’s Next?

We’re excited to get this release into your hands, so if you’ve haven’t downloaded it yet, then go download Android Studio 1.0 right now! To take advantage of Cloud Tools for Android Studio, you’ll want to sign up for a free Google Cloud Platform trial. Nothing is stopping you from building great Android apps from front to back. If you’ve got suggestions, drop us a line so that we can keep improving. We’re just getting started putting Google Cloud Platform tools in your hands. We can’t wait to see what you’ll build.

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Google Play game services ends year with a bang!

Posted by Benjamin Frenkel, Product Manager, Play Games

In an effort to supercharge our Google Play games services (GPGS) developer tools, we’re introducing the Game services Publishing API, a revamped Unity Plugin, additional enhancements to the C++ SDK, and improved Leaderboard Tamper Protection.

Let’s dig into what’s new for developers:

Publishing API to automate game services configuration

At Google I/O this past June, the pubsite team launched the Google Play Developer Publishing APIs to automate the configuration and publishing of applications to the Play store. Game developers can now also use the Google Play game services Publishing API to automate the configuration and publishing of game services resources, starting with achievements and leaderboards.

For example, if you plan on publishing your game in multiple languages, the game services Publishing API will enable you to pull translation data from spreadsheets, CSVs, or a Content Management System (CMS) and automatically apply those translations to your achievements.

Early adopter Square Enix believes the game services Publishing API will be an indispensable tool to manage global game rollouts:

Achievements are the most used feature in Google Play game services for us. As our games support more languages, achievement management has become increasingly difficult. With the game services Publishing API, we can automate this process, which is really helpful. The game services Publishing API also comes with great samples that we were able to easily customize for our needs

Keisuke Hata, Manager / Technical Director, SQUARE ENIX Co., Ltd.

To get started today, take a look at the developer documentation here.

Updated Unity plugin and Cross-platform C++ SDK

• Unity plugin Saved Games support: You can now take advantage of the Saved Games feature directly from the Unity plugin, with more storage and greater discoverability through the Play Games app


• New Unity plugin architecture: We’ve rewritten the plugin on top of our cross-platform C++ SDK to speed up feature development across SDKs and increase our responsiveness to your feedback


• Improved Unity generated Xcode project setup: You now have a much more robust way to generate Xcode projects integrated with Google Play Game Services in Unity


• Updated and improved Unity samples: We’ve updated our sample codes to make it easier for first time developers to integrate Google Play games services


• C++ SDK support for iPhone 6 Plus: You can now take advantage of the out-of-box games services UI (e.g., for leaderboards and achievements) for larger form factor devices, such as the iPhone 6 Plus

We also include some important bug fixes and stability improvements. Check out the release notes for the Unity Plugin and the getting started page for the C++ SDK for more details.

Leaderboard Tamper Protection

Turn on Leaderboard Tamper Protection to automatically hide suspected tampered scores from your leaderboards. To enable tamper protection on an existing leaderboard, go to your leaderboard in the Play developer console and flip the “Leaderboard tamper protection” toggle to on. Tamper protection will be on by default for new leaderboards.Learn more.

To learn more about cleaning up previously submitted suspicious scores refer to the Google Play game services Management APIs documentation or get the web demo console for the Management API directly from github here.

In addition, if you prefer command-line tools, you can use the python-based option here.

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Making a performant watch face

Posted by Hoi Lam, Developer Advocate, Android Wear

What’s a better holiday gift than great performance? You’ve got a great watch face idea -- now, you want to make sure the face you’re presenting to the world is one of care and attention to detail.

At the core of the watch face's process is an onDraw method for canvas operations. This allows maximum flexibility for your design, but also comes with a few performance caveats. In this blog post, we will mainly focus on performance using the real life journey of how we optimised the Santa Tracker watch face, more than doubling the number of fps (from 18 fps to 42 fps) and making the animation sub-pixel smooth.

Starting point - 18 fps

Our Santa watch face contains a number of overlapping bitmaps that are used to achieve our final image. Here's a list of them from bottom to top:

1. Background (static)


2. Clouds which move to the middle


3. Tick marks (static)


4. Santa figure and sledge (static)


5. Santa’s hands - hours and minutes


6. Santa’s head (static)

The journey begins with these images...

Large images kill performance (+14 fps)

Image size is critical to performance in a Wear application, especially if the images will be scaled and rotated. Wasted pixel space (like Santa’s arm here) is a common asset mistake:

Before: 584 x 584 = 341,056 pixels	After: 48*226 = 10,848 (97% reduction)

It's tempting to use bitmaps from the original mock up that have the exact location of watch arms and components in absolute space. Sadly, this creates problems, like in Santa's arm here. While the arm is in the correct position, even transparent pixels increase the size of the image, which can cause performance problems due to memory fetch. You'll want to work with your design team to extract padding and rotational information from the images, and rely on the system to apply the transformations on our behalf.

Since the original image covers the entire screen, even though the bitmap is mostly transparent, the system still needs to check every pixel to see if they have been impacted. Cutting down the area results in significant gains in performance. After correcting both of the arms, the Santa watch face frame rate increased by 10 fps to 28 fps (fps up 56%). We saved another 4 fps (fps up 22%) by cropping Santa’s face and figure layer. 14 fps gained, not bad!

Combine Bitmaps (+7 fps)

Although it would be ideal to have the watch tick marks on top of our clouds, it actually does not make much difference visually as the clouds themselves are transparent. Therefore there is an opportunity to combine the background with the ticks.

+

When we combined these two views together, it meant that the watch needed to spend less time doing alpha blending operations between them, saving precious CPU time. So, consider collapsing alpha blended resources wherever we can in order to increase performance. By combining two full screen bitmaps, we were able to gain another 7 fps (fps up 39%).

Anti-alias vs FilterBitmap flags - what should you use? (+2 fps)

Android Wear watches come in all shapes and sizes. As a result, it is sometimes necessary to resize a bitmap before drawing on the screen. However, it is not always clear what options developers should select to make sure that the bitmap comes out smoothly. With canvas.drawBitmap, developers need to feed in a Paint object. There are two important options to set - they are anti-alias and FilterBitmap. Here’s our advice:

• Anti-alias does not do anything for bitmaps with transparent edges. We often switch on the anti-alias option by default as developers when we are creating a Paint object. However, this option only really makes sense for vector objects. For bitmaps, this is used to blend the rectangular edges if it is rotated or skewed and it has no impact if the edge pixels are transparent (as we would imagine most watch face arms would be). The hand on the left below has anti-alias switched on, the one on the right has it switched off. So turn off anti-aliasing for bitmaps to gain performance back. For our watch face, we gained another 2 fps (fps up 11%) by switching this option off.




• Switch on FilterBitmap for all bitmap objects which are on top of other objects - this option smooths the edges when drawBitmap is called. This should not be confused with the filter option on Bitmap.createScaledBitmap for resizing bitmaps. We need both to be turned on. The bitmaps below are the magnified view of Santa’s hand. The one on the left has FilterBitmap switched off and the one on the right has FilterBitmap switched on.

Eliminate expensive calls in the onDraw loop (+3 fps)

onDraw is the most critical function call in watch faces. It's called for every drawable frame, and the actual painting process cannot move forward until it's finished. As such, our onDraw method should be as light and as performant as possible. Here's some common problems that developers run into that can be avoided:

1. Do move heavy and common code to a precompute function - e.g. if we commonly grab R.array.cloudDegrees, try doing that in onCreate, and just referencing it in the onDraw loop.


2. Don’t repeat the same image transform in onDraw - it’s common to resize bitmaps at runtime to fit the screen size but this is not available in onCreate. To avoid resizing the bitmap over and over again in onDraw, override onSurfaceChanged where width and height information are available and resize images there.


3. Don't allocate objects in onDraw - this leads to high memory churn which will force garbage collection events to kick off, killing frame rates.


4. Do analyze the CPU performance by using a tool such as the Android Device Monitor. It’s important that the onDraw execution time is short and occurs in a regular period.

Following these simple rules will improve rendering performance drastically.

In the first version, the Santa onDraw routine has a rogue line:

int[] cloudDegrees = 
    getResources().getIntArray(R.array.cloudDegrees);

This loads the int array on every call from resources which is expensive. By eliminating this, we gained another 3 fps (fps up 17%).

Sub-pixel smooth animation (-2 fps)

For those keeping count, we should be 44 fps, so why is the end product 42 fps? The reason is a limitation with canvas.drawBitmap. Although this command takes left and top positioning settings as a float, the API actually only deals with integers if it is purely translational for backwards compatibility reasons. As a result, the cloud can only move in increments of a whole pixel resulting in janky animations. In order to be sub-pixel smooth, we actually need to draw and then rotate rather than having pre-rotate clouds which moves towards Santa. This additional rotation costs us 2 fps. However, the effect is worthwhile as the animation is now sub-pixel smooth.

Before - fast but janky and wobbly

for (int i = 0; i < mCloudBitmaps.length; i++) {
    float r = centerX - (timeElapsed / mCloudSpeeds[i]) % centerX;
    float x = centerX + 
        -1 * (r * (float) Math.cos(Math.toRadians(cloudDegrees[i] + 90)));
    float y = centerY - 
        r * (float) Math.sin(Math.toRadians(cloudDegrees[i] + 90));
    mCloudFilterPaints[i].setAlpha((int) (r/centerX * 255));
    Bitmap cloud = mCloudBitmaps[i];
    canvas.drawBitmap(cloud,
        x - cloud.getWidth() / 2,
        y - cloud.getHeight() / 2,
        mCloudFilterPaints[i]);
}

After - slightly slower but sub-pixel smooth

for (int i = 0; i < mCloudBitmaps.length; i++) {
    canvas.save();
    canvas.rotate(mCloudDegrees[i], centerX, centerY);
    float r = centerX - (timeElapsed / (mCloudSpeeds[i])) % centerX;
    mCloudFilterPaints[i].setAlpha((int) (r / centerX * 255));
    canvas.drawBitmap(mCloudBitmaps[i], centerX, centerY - r,
        mCloudFilterPaints[i]);
    canvas.restore();
}

Before: Integer translation values create janky, wobbly animation. After: smooth sailing!

Quality on every wrist

The watch face is the most prominent UI element in Android Wear. As craftspeople, it is our responsibility to make it shine. Let’s put quality on every wrist!

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New Code Samples for Lollipop

Posted by Trevor Johns, Developer Programs Engineer

With the launch of Android 5.0 Lollipop, we’ve added more than 20 new code samples demonstrating how to implement some of the great new features of this release. To access the code samples, you can easily import them in Android Studio 1.0 using the new Samples Wizard.

Go to File > Import Sample in order to browse the available samples, which include a description and preview for each. Once you’ve made your selection, select “Next” and a new project will be automatically created for you. Run the project on an emulator or device, and feel free to experiment with the code.

Samples Wizard in Android Studio 1.0

Newly imported sample project in Android Studio

Alternatively, you can browse through them via the Samples browser on the developer site. Each sample has an Overview description, Project page to browse app file structure, and Download link for obtaining a ZIP file of the sample. As a third option, code samples can also be accessed in the SDK Manager by downloading the SDK samples for Android 5.0 (API 21) and importing them as existing projects into your IDE.

Sample demonstrating transition animations

Material Design

When adopting material design, you can refer to our collection of sample code highlighting material elements:

• Floating action button


• Reveal effect


• CardView


• Drawable tinting


• Elevation


• Drag-and-drop with elevation


• View clipping


• Animation interpolators

For additional help, please refer to our design checklist, list of key APIs and widgets, and documentation guide.

To view some of these material design elements in action, check out the Google I/O app source code.

Platform

Lollipop brings the most extensive update to the Android platform yet. The Overview screen allows an app to surface multiple tasks as concurrent documents. You can include enhanced notifications with this sample code, which shows you how to use the lockscreen and heads-up notification APIs.

We also introduced a new Camera API to provide developers more advanced image capture and processing capabilities. These samples detail how to use the camera preview and take photos, how to record video, and implement a real-time high-dynamic range camera viewfinder.

Elsewhere, Project Volta encourages developers to make their apps more battery-efficient with new APIs and tools. The JobScheduler sample demonstrates how you can schedule background tasks to be completed later or under specific conditions.

For those interested in the enterprise device administration use case, there are sample apps on setting app restrictions and creating a managed profile.

Android Wear

For Android Wear, we have a speed tracker sample to show how to take advantage of GPS support on wearables. You can browse the rest of the Android Wear samples too, and here are some highlights that demonstrate the unique capabilities of wearables, such as data synchronization, notifications, and supporting round displays:

• DataLayer


• FindMyPhone


• GridViewPager


• Notifications


• RecipeAssistant


• SynchronizedNotifications


• WatchViewStub

Android TV

Extend your app for Android TV using the Leanback library described in this training guide and sample.

To try out a game that is specifically optimized for Android TV, download Pie Noon from Google Play. It’s an open-source game developed in-house at Google that supports multiple players using Bluetooth controllers or touch controls on mobile devices.

Android Auto

For the use cases highlighted in the Introduction to Android Auto DevByte, we have two code samples. The Media Browser sample (DevByte) demonstrates how easy it is to make an audio app compatible with Android Auto by using the new Lollipop media APIs, while the Messaging sample (DevByte) demonstrates how to implement notifications that support replies using speech recognition.

Google Play services

Since we’ve discussed sample resources for the Android platform and form factors, we also want to mention that there are existing samples for Google Play services. With Google Play services, your app can take advantage of the latest Google-powered APIs such as Maps, Google Fit, Google Cast, and more. Access samples in the Google Play services SDK or visit the individual pages for each API on the developer site. For game developers, you can reference the Google Play Games services samples for how to add achievements, leaderboards, and multiplayer support to your game.

Check out a sample today to help you with your development!

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