Tag Archives: Android Studio

13 Things to know for Android developers at Google I/O!

Posted by Maru Ahues Bouza, Director of Android Developer Relations

Android I/O updates: Jetpack, Wear OS, etc

There aren’t many platforms where you can build something and instantly reach billions of people around the world, not only on their phones—but their TVs, cars, tablets, watches, and more. Today, at Google I/O, we covered a number of ways Android helps you make the most of this opportunity, and how Modern Android Development brings as much commonality as possible, to make it faster and easier for you to create experiences that tailor to all the different screens we use in our daily lives.

We’ve rounded up the top 13 things to know for Android developers—from Jetpack Compose to tablets to Wear OS and of course… Android 13! And stick around for Day 2 of Google I/O, when Android’s full track of 26 technical talks and 4 workshops drop. We’re also bringing back the Android fireside Q&A in another episode of #TheAndroidShow; tweet us your questions now using #AskAndroid, and we’ve assembled a team of experts to answer live on-air, May 12 at 12:30PM PT.

MODERN ANDROID DEVELOPMENT

#1: Jetpack Compose Beta 1.2, with support for more advanced use cases

Android’s modern UI toolkit, Jetpack Compose, continues to bring the APIs you need to support more advanced use cases like downloadable fonts, LazyGrids, window insets, nested scrolling interop and more tooling support with features like LiveEdit, Recomposition Debugging and Animation Preview. Check out the blog post for more details.

#2: Android Studio: introducing Live Edit

Get more done faster with Android Studio Dolphin Beta and Electric Eel Canary! Android Studio Dolphin includes new features and improvements for Jetpack Compose and Wear OS development and an updated Logcat experience. Android Studio Electric Eel comes with integrations with the new Google Play SDK Index and Firebase Crashlytics. It also offers a new resizable emulator to test your app on large screens and the new Live Edit feature to immediately deploy code changes made within composable functions. Watch the What’s new in Android Development Tools session and read the Android Studio I/O blog post here.

#3: Baseline Profiles - speed up your app load time!

The speed of your app right after installation can make a big difference on user retention. To improve that experience, we created Baseline Profiles. Baseline Profiles allow apps and libraries to provide the Android runtime with metadata about code path usage, which it uses to prioritize ahead-of-time compilation. We've seen up to 30% faster app startup times thanks to adding baseline profiles alone, no other code changes required! We’re already using baseline profiles within Jetpack: we’ve added baselines to popular libraries like Fragments and Compose – to help provide a better end-user experience. Watch the What’s new in app performance talk, and read the Jetpack blog post here.

BETTER TOGETHER

#4: Going big on Android tablets

Google is all in on tablets. Since last I/O we launched Android 12L, a release focused on large screen optimizations, and Android 13 includes all those improvements and more. We also announced the Pixel tablet, coming next year. With amazing new hardware, an updated operating system & Google apps, improved guidelines and libraries, and exciting changes to the Play store, there has never been a better time to review your apps and get them ready for large screens and Android 13. That’s why at this year’s I/O we have four talks and a workshop to take you from design to implementation for large screens.

#5: Wear OS: Compose + more!

With the latest updates to Wear OS, you can rethink what is possible when developing for wearables. Jetpack Compose for Wear OS is now in beta, so you can create beautiful Wear OS apps with fewer lines of code. Health Services is also now in beta, bringing a ton of innovation to the health and fitness developer community. And last, but certainly not least, we announced the launch of The Google Pixel Watch - coming this Fall - which brings together the best of Fitbit and Wear OS. You can learn more about all the most exciting updates for wearables by watching the Wear OS technical session and reading our Jetpack Compose for Wear OS announcement.

#6: Introducing Health Connect

Health Connect is a new platform built in close collaboration between Google and Samsung, that simplifies connectivity between apps making it easier to reach more users with less work, so you can securely access and share user health and fitness data across apps and devices. Today, we’re opening up access to Health Connect through Jetpack Health—read our announcement or watch the I/O session to find out more!

#7: Android for Cars & Android TV OS

Android for Cars and Android TV OS continue to grow in the US and abroad. As more users drive connected or tune-in, we’re introducing new features to make it even easier to develop apps for cars and TV this year. Catch the “What’s new with Android for Cars” and “What's new with Google TV and Android TV” sessions on Day 2 (May 12th) at 9:00 AM PT to learn more.

#8: Add Voice Across Devices

We’re making it easier for users to access your apps via voice across devices with Google Assistant, by expanding developer access to Shortcuts API for Android for Cars, with support for Wear OS apps coming later this year. We’re also making it easier to build those experiences with Smarter Custom Intents, enabling Assistant to better detect broader instances of user queries through ML, without any NLU training heavy lift. Additionally, we’re introducing improvements that drive discovery to your apps via voice on Mobile, first through Brandless Queries, that drive app usage even when the user hasn’t explicitly said your app’s name, and App Install Suggestions that appear if your isn’t installed yet–these are automatically enabled for existing App Actions today.

AND THE LATEST FROM ANDROID, PLAY, AND MORE:

#9: What’s new in Play!

Get the latest updates from Google Play, including new ways Play can help you grow your business. Highlights include the ability to deep-link and create up to 50 custom listings; our LiveOps beta, which will allow more developers to submit content to be considered for featuring on the Play Store; and even more flexibility in selling subscriptions. Learn about these updates and more in our blog post.

#10: Google Play SDK Index

Evaluate if an SDK is right for your app with the new Google Play SDK index. This new public portal lists over 100 of the most widely used commercial SDKs and information like which app permissions the SDK requests, statistics on the apps that use them, and which version of the SDK is most popular. Learn more on our blog post and watch “What’s new in Google Play” and “What’s new in Android development tools” sessions.

#11: Privacy Sandbox on Android

Privacy Sandbox on Android provides a path for new advertising solutions to improve user privacy without putting access to free content and services at risk. We recently released the first Privacy Sandbox on Android Developer Preview so you can get an early look at the SDK Runtime and Topics API. You can conduct preliminary testing of these new technologies, evaluate how you might adopt them for your solutions, and share feedback with us.

#12: The new Google Wallet API

The new Google Wallet gives users fast and secure access to everyday essentials across Android and Wear OS. We’re enhancing the Google Wallet API, previously called Google Pay Passes API, to support generic passes, grouping and mixing passes together, for example grouping an event ticket with a voucher, and launching a new Android SDK which allows you to save passes directly from your app without a backend integration. To learn more, read the full blog post, watch the session, or read the docs at developers.google.com/wallet.

#13: And of course, Android 13!

The second Beta of Android 13 is available today! Get your apps ready for the latest features for privacy and security, like the new notification permission, the privacy-protecting photo picker, and improved permissions for pairing with nearby devices and accessing media files. Enhance your app with features like app-specific language support and themed app icons. Build with modern standards like HDR video and Bluetooth LE Audio. You can get started by enrolling your Pixel device here, or try Android 13 Beta on select phones, tablets, and foldables from our partners - visit developer.android.com/13 to learn more.

That’s just a snapshot of some of the highlights for Android developers at this year’s Google I/O. Be sure to watch the What’s New in Android talk to get the landscape on the full Android technical track at Google I/O, which includes 26 talks and 4 workshops. Enjoy!

Source: Android Developers Blog

Google I/O 2022: What’s new in Android Development Tools

Posted by Juan Sebastian Oviedo, Senior Product Manager

Today at Google I/O 2022, we announced an exciting set of new features available in Android Studio Dolphin Beta and Electric Eel Canary, both available for download. You told us that you want to be more productive while creating Android apps, so we focused on improvements that make the development experience faster and more informative.

In the Android Studio Dolphin release you will find the following features and improvements that you can start using in the Beta channel, which is close to stable quality:

View Compose animations and coordinate them with Animation Preview.
Define annotation classes to easily include and apply multiple Compose preview definitions at once.
Track recomposition counts for your composables in the Layout Inspector.
Easily pair and control Wear OS emulators and launch tiles, watch faces, and complications directly from Android Studio.
Diagnose app issues faster with Logcat V2.

For even more cutting edge features, you can take a sneak peek at the Android Studio Electric Eel release in the Canary channel:

View dependency insights from the new Google Play SDK Index, a public portal with information about popular dependencies/SDKs. If a specific version of a library has been marked as “outdated” by its author, a corresponding Lint warning will appear when viewing that dependency definition. This enables you to discover and update dependency issues during development instead of later when you go to publish your app on the Play Console. You can learn more about this new tool here.
See Firebase Crashlytics reports directly in Android Studio using the new App Quality Insights window. The App Quality Insights window allows you to navigate from stack traces into your code with a few simple clicks. The IDE also highlights lines of code in the editor as you're editing files containing recent crashes. This saves you time by presenting actionable crash information from users directly in the IDE, so you can focus on providing your users with the best app experience.
Test your app’s UI on representative reference devices using a single resizable Android Emulator. Instead of having to set up emulators specifically for tablets, phones, or desktops, you can use a single resizable emulator and change its configuration without needing to re-deploy to test your app.
With the experimental Live Edit feature, make code changes and have those immediately reflected in the Compose Preview and running app on an emulator or physical device.

These features will be promoted to more stable channels once we have your feedback and make improvements, so please try them out.

To see all the new features in action, watch the What’s new in Android Developer Tools session.

Below is a list of key new features and improvements in Android Studio Dolphin:

Jetpack Compose

Compose Animation Coordination - See all your animations at once and coordinate them in Animation Preview. You can also freeze a specific animation.

Compose Animation Coordination

Compose Multipreview Annotations - Define an annotation class that includes multiple Preview definitions and use that new annotation to generate those previews at once. Use this new annotation to preview multiple devices, fonts, and themes at the same time — without repeating those definitions for every single composable.

Multipreview annotations

Compose Recomposition Counts in Layout Inspector - View recomposition counts for a Compose app in the Layout Inspector. Recomposition counts and skip counts can optionally be shown in the Component Tree and Attributes panels. Learn more.

Compose Recomposition Counts

Wear OS

Wear OS Emulator Pairing Assistant - Using the Wear OS Emulator Pairing Assistant, you can now see Wear Devices in the Device Manager, and pair multiple watch emulators with a single phone. You also don't have to re-pair devices as often because Android Studio remembers pairings after being closed.

Wear OS Emulator Pairing Assistant

Wear OS Emulator Side Toolbar - Use Wear-specific emulator buttons that resemble and simulate physical buttons, including main buttons, palm buttons, and tilt buttons.

Wear OS Emulator Side Toolbar

Wear OS Direct Surface Launch - Create Run/Debug configurations for Wear OS tiles, watch faces, and complications, and launch them directly from Android Studio.

New Wear OS Run/Debug configuration types

Development tools

Logcat V2 - Rebuilt from the ground up, the new Logcat makes it easier to parse, query, and track logs. Logcat V2 includes new formatting that makes it easier to scan useful information, new split views to allow you to track more at a glance, and a brand new powerful syntax for filtering logs. Learn more.

Logcat V2

Gradle Managed Devices - Describe the virtual devices you need for your automated tests as a part of your build, and let Gradle take care of the rest. From SDK downloading, to device provisioning and setup, to test execution and teardown, Gradle manages the lifecycle of your virtual devices during instrumentation tests. Gradle is also able to apply intelligent functionality, such as snapshot management, test caching, and test sharding to ensure your tests run efficiently, quickly, and consistently. Gradle Managed Devices also introduces a completely new type of device, called the Automated Test Device, which optimizes devices for automated tests, resulting in significant reduction in CPU and memory usage during test execution. Learn more.

Gradle Managed Devices

Below is a list of key new features and improvements in Android Studio Electric Eel:

Jetpack Compose

Live Edit - Make code changes to Composables in Android Studio and see those changes reflected immediately in the Compose Preview and your emulator or physical device. Live Edit is an opt-in feature that you can enable in Android Studio settings. Learn more.

Live Edit on emulator

Live Edit on Preview

Google Play and Firebase

SDK Insights - Get Lint warnings for SDKs/libraries that have been marked as outdated by their authors in the Google Play SDK Index. Update outdated dependency versions during development to avoid issues when your app is submitted to the Play Console.

Google Play SDK Index insights

App Quality Insights from Firebase Crashlytics - Discover, investigate, and resolve issues reported by Crashlytics in Android Studio and within the context of your local source code. This integration helps reduce friction when navigating from crashes to code (and from code to crash), and surfaces important contextual data about each crash to help you reproduce issues locally.

App Quality Insights from Firebase Crashlytics

Large Screens

Resizable Emulator - Rapidly toggle between representative reference devices to quickly test various application layout states with a single running emulator instance. You can create these emulators by selecting the “Resizable” type in the Device Manager’s “Create device” flow.

Resizable Emulator

Visual Linting - Discover and fix your layout issues across different devices (for example, when a button is hidden out of bounds on a larger tablet) by opening the Layout Validation panel. We automatically run your layout to check for Visual Lint issues across different screen sizes.

Visual Linting

Development Tools

Emulated Bluetooth - You can now discover and connect two phone emulators using virtual Bluetooth. This feature is available on Android Emulator 31.3.8 and higher with system image T (API 33). We plan to add more support for creating sample virtual peripherals, such as beacons and heart rate monitors, and integration testing for your Bluetooth features!

Pairing two Android Emulators using Emulated Bluetooth

Device Mirroring - Minimize the number of interruptions when developing by streaming your device display directly to Android Studio. Device Mirroring gives you the ability to interact with a physical device using the Running Devices window in Studio. To enable this feature, go to Preferences > Experimental and select Device Mirroring. Once enabled, plug in your device and open the Running Devices window to begin streaming your display.

Device Mirroring

To recap, these new features and improvements are available in the Android Studio Dolphin Beta, near stable quality:

Jetpack Compose

Compose Animation Coordination
Compose Multipreview Annotations
Compose Recomposition Counts in Layout Inspector

Wear OS

Wear OS Emulator Pairing Assistant
Wear OS Emulator Side Toolbar
Wear OS Direct Surface Launch

Development tools

Logcat V2
Gradle Managed Devices

These brand new features and improvements are available in the Android Studio Electric Eel Canary:

Jetpack Compose

Live Edit

Google Play and Firebase

SDK Insights
App Quality Insights from Firebase Crashlytics

Large Screens

Resizable Emulator
Visual Linting

Development tools

Emulated Bluetooth
Device Mirroring

Getting started

Android Studio Dolphin Beta and Electric Eel Canary are both available for download. You can install them side by side with the current stable version of Android Studio following these instructions. The Beta release is near stable release quality, but bugs might still exist, so, if you do find an issue, please let us know so we can work to fix it. Likewise, if you find an issue or have feedback for the features in the Canary release, please let us know.

We really appreciate your feedback on issues and feature requests. You can follow us—the Android Studio development team—on Twitter and on Medium.

Check out the preview release notes for more details.

Source: Android Developers Blog

What’s new in Jetpack Compose

Posted by Jolanda Verhoef, Android Developer Relations Engineer, and Anna-Chiara Bellini, Android Toolkit UI Product Manager

It’s been almost a year since Jetpack Compose 1.0 was released, and during this time we've seen the community adopt it with enthusiasm. You’ve told us you’re appreciating the conciseness of the Kotlin syntax and the declarative approach that makes thinking about UI so much faster and easier.

Compose in the Community

We've seen many companies adopt Compose at scale for the newest and boldest features of their apps. For instance, we've worked closely with the Play Store team, who started experimenting with Compose in the very early days, and learned that not only is it more enjoyable, it is beneficial to their developer productivity. They told us that "All new Play Store features are built on top of this framework. Compose has been instrumental in unlocking better velocity and smoother landings for the app." The team at Twitter has been using Jetpack Compose across different parts of the app, and they are reaping the benefits, as "Compose makes it much easier to define our own components and to make their API contracts more explicit, flexible, and intuitive." The Airbnb team adopted Compose as well: "Jetpack Compose is a critical part of our technical strategy. The productivity gains are massive."

We're very glad to see that these teams, who have carefully evaluated Compose in large, complex production environments, are experiencing not just more fun and clarity in their UI development, but broader engineering benefits! And these are just a few examples, because over 100 of the top 1000 apps in the Play Store are now using Compose.

These close collaborations, and listening carefully to feedback from the broader Android community, are always at the heart of our development process and are key to advancing our roadmap. We're now focusing on supporting your more advanced use cases, with new APIs and feature improvements, all together with new tools to make building with Compose easier. We know that Compose fundamentally changes the way UI is built. To help you with the necessary mindset shift, we're publishing more guidance, talks and codelabs on advanced topics, and more in-depth videos so you can write apps that look great and perform great. Here's what is new:

Compose 1.2 beta

Today, we’re releasing the first beta version of Compose 1.2, which includes a lot of features and improvements.

Text improvements

Font Padding

We’ve addressed one of the top-voted bugs in our issue tracker by making includeFontPadding a customizable parameter. We recommend you set this value to false, as this will enable more precise alignment of text within layout. We aim to eventually make this the default value in a future release. Please let us know in the issue above if setting the value to false leads to issues with your app. Additionally, when includeFontPadding is set to false, you can adapt the line height of your Text composable by setting the lineHeightStyle parameter. Combined it can look like this:

Multi-line Text with includeFontPadding set to true (left, current default) vs false (right) and lineHeightStyle.

Text(
 text = myText,
 style = TextStyle(
   lineHeight = 2.5.em,
   platformStyle = PlatformTextStyle(
     includeFontPadding = false
   ),
   lineHeightStyle = LineHeightStyle(
     alignment = Alignment.Center,
     trim = Trim.None
   )
 )
)

Downloadable Fonts

Compose 1.2 also introduces downloadable fonts in Compose. You can use the new APIs for Compose to access Google Fonts asynchronously, even defining fallback fonts, without any complex setup. With downloadable fonts, you can keep your APK size small and improve your user’s system health as multiple apps can share the same font through a provider.

Text Magnifier

Android text provides a magnifier widget, which makes selecting text easier. Compose now supports the text magnifier.

The magnifier is shown when dragging a selection handle to help you see what’s under your finger. Compose 1.1.0 brought the magnifier to selection within text fields, and now Compose 1.2.0 supports magnifier in both text fields and SelectionContainer. The magnifier has also been enhanced to match the precise behavior of the Android magnifier in Views.

Layout features and improvements

Lazy Layouts

Lazy layouts continue to evolve, with the grid APIs LazyVerticalGrid and LazyHorizontalGrid graduating out of experimental, and a new experimental API being added, called LazyLayout, that lets you implement your own custom lazy layouts. Learn more about these APIs in the I/O talk Lazy layouts in Compose.

Interop with CoordinatorLayout

When you embed a scrolling composable in a CoordinatorLayout from the view system, you can now make sure their scroll behaviors are interoperable. This makes the setup of a collapsible toolbar much easier. You can opt-in to this behavior by passing the result of calling the new experimental rememberNestedScrollInteropConnection method into the nestedScroll modifier. Here’s a sample demonstrating this new functionality.

Window insets

The insets library in Accompanist has now graduated to the Compose Foundation library, using the WindowInsets class. Read more about it in our documentation on Integrating Compose with your existing UI.

Window size classes

To make it easier to design, develop and test resizable layouts, we’ve released window size classes - a set of opinionated viewport breakpoints. They are now available in alpha in a new library material3-window-size-class, as part of the Material 3 set of libraries. You can read more about size classes in the Supporting different screen sizes documentation and take a look at a sample implementation in Crane.

Focus on performance

To help you understand and improve your app’s performance, we focused a lot on new performance tooling and guidance. With this, it becomes much easier to understand why and where your app might be lagging.

Starting from Android Studio Dolphin, you can inspect how often composables recompose using the Layout Inspector. Unexpectedly high numbers of recomposition can point you to a composable that could be optimized. In addition, Android Studio Electric Eel now includes a recomposition highlighter, a visual aid to see which composables recompose when. Read more about this new tooling in the What’s new in Android Studio blog.

Layout Inspector showing recomposition count and recomposition highlighter.

Compose changes the way you write your UI at a fundamental level, so there are some best practices that you can adopt to make sure your app is performant. The newly released documentation page suggests how to write and configure your Compose app for best performance. In the I/O talk Common performance gotchas in Jetpack Compose, the Compose team describe common performance mistakes and how to fix them.

Performance is an ongoing area of focus and we’re working hard on improving and extending tooling and guidance. In the meantime, we’d really appreciate your feedback on the work we’ve done so far. Please raise your bugs in the issue tracker or ask your questions on the KotlinLang Slack group.

New tools

On top of improvements, there are also new tooling updates to help you use Compose more effectively. Android Studio Dolphin, now in Beta, brings exciting features for Compose development. Beyond recomposition counts, new tools include Animation Coordination so you can see and scrub through all your animations at once, and the MultiPreview annotation to help you build for multiple screen sizes. To enable you to iterate faster Android Studio Electric Eel (in Canary) brings LiveEdit.

Gif of Android Studio. On left side there is code and the right side there is a celebration text for Android Developers reaching one million subscribers on YouTube.

Check out What's new in Android Development Tools for all the details, and make sure you share your feedback to help shape the tooling support you need for Compose.

Compose for Wear OS

If there is something better than Compose, it is more Compose! So we're very excited to see Compose for Wear OS moving to Beta! Following the same principle as any other Jetpack library, Beta means that it's feature complete and API stable, and you can start building your production-ready apps. Go ahead and watch the talk, and read the blog post!

New and improved guidance

We’ve added and revamped a lot of the guidance on Compose:

New workshop and revamped codelab on State in Compose
New workshop and revamped codelab on Basic layouts in Compose
New performance documentation
Updated documentation on Custom Input
I/O talks Common performance gotchas in Jetpack Compose and Lazy layouts in Compose
For those who are new to programming, the Android Basics with Compose course is now available

Happy Composing!

We hope that you find these new features as exciting as we do. If you haven't started yet, it's time to learn Jetpack Compose and see how it will fit in your team and development process, so that you can experience all the benefits of improved velocity and developer productivity. Happy Composing!

Source: Android Developers Blog

Android Studio Chipmunk

Posted by Paris Hsu, Product & Design, Android; Takeshi Hagikura, Developer Relations Engineer, Android

Today, we are thrilled to announce the stable release of Android Studio Chipmunk 🐿: The official IDE for building Android applications! This release is a smaller feature release, but we included the latest IntelliJ update and devoted more time to quality and stability. In this release alone, we address over 175+ quality issues.

If you want to be on the latest stable version of Android Studio you can download it today!

What’s in Android Studio Chipmunk

Below is a full list of new features in Android Studio Chipmunk:

Compose Animation Preview

This previously experimental feature is now available to allow Jetpack Compose developers to inspect and debug their animations built with Compose. If an animation is described in a composable preview, you can inspect the exact value of each animated value at a given time, pause the animation, loop it, fast-forward it, or slow it down. It is especially useful to compare animations with their design specs frame by frame.

Compose Animation Preview currently supports AnimatedVisibility and updateTransition. It will support more animation types in the future.

Compose Animation Shrine Cart

CPU Profiler

Android Studio Chipmunk now shows updated jank information, including jank types, and expected and actual deadlines that help you spot the actual cause of the jank. This jank information is available when you use the Android Emulator or physical devices with API level 31 (Android 12) or higher. Learn more here.

Showing Jank Information in CPU Profiler

Build Analyzer: Check Jetifier

In Chipmunk we have introduced a new Jetifier check in Build Analyzer that will notify you if you can remove the Jetifier flag to improve performance during build.

The Jetifier flag was designed to automatically migrate third-party libraries to use AndroidX, and the vast majority of Android Studio projects still have it enabled. However, the library ecosystem has mostly moved to support AndroidX natively, and having the flag now usually adds unnecessary build overhead -- turning it off will typically save 5-10% on build times.

Showing Jetifier Check in Build Analyzer

IntelliJ Platform Update

Although the number of Android specific features is light for Android Studio Chipmunk, it however includes the IntelliJ 2021.2 platform major release 😎, which has many new features such as project-wide analysis, a new powerful Package Search UI, and IDE actions enhancements to speed up your workflow. Learn more.

Getting Started

In short, Android Studio Chipmunk 🐿 is the update you don’t want to miss! Even though it was a shorter release, with the new version for IntelliJ, our continual efforts to improve quality, performance, and stability of the IDE, and the features listed earlier, we can’t wait for you to download and try it today!

As always, we appreciate any feedback on things you like, and issues or features you would like to see. If you find a bug or issue, please file an issue. To stay up-to-date with the latest features, follow us -- the Android Studio development team ‐ on Twitter and on Medium.

Source: Android Developers Blog

Play Time with Jetpack Compose

Learn about Google Play Store’s strategy for adopting Jetpack Compose, how they overcame specific performance challenges, and improved developer productivity and happiness.

Posted by Andrew Flynn & Jon Boekenoogen, Tech leads on Google Play

In 2020, Google Play Store engineering leadership made the big decision to revamp its entire storefront tech stack. The existing code was 10+ years old and had incurred tremendous tech debt over countless Android platform releases and feature updates. We needed new frameworks that would scale to the hundreds of engineers working on the product while not negatively impacting developer productivity, user experience, or the performance of the store itself.

We laid out a multi-year roadmap to update everything in the store from the network layer all the way to the pixel rendering. As part of this we also wanted to adopt a modern, declarative UI framework that would satisfy our product goals around interactivity and user delight. After analyzing the landscape of options, we made the bold (at the time) decision to commit to Jetpack Compose, which was still in pre-Alpha.

Since that time, the Google Play Store and Jetpack Compose teams at Google have worked extremely closely together to release and polish a version of Jetpack Compose that meets our specific needs. In this article we'll cover our approach to migration as well as the challenges and benefits we found along the way, to share some insight into what adopting Compose can be like for an app with many contributors.

Play Store rewrote their UI with 50% less code with Compose

Considerations

When we were considering Jetpack Compose for our new UI rendering layer, our top two priorities were:

Developer Productivity: Play Store team has hundreds of engineers contributing to this code, so it should be easy (and fun) to develop against.
Performance: Play Store renders lots of media-heavy content with many business metrics that are very sensitive to latency and jank, so we needed to make sure it performed well across all devices, especially low-memory hardware and Android (Go Edition) devices.

Developer Productivity

We have been writing UI code using Jetpack Compose for over a year now and enjoy how Jetpack Compose makes UI development more simple.

We love that writing UI requires much less code, sometimes up to 50%. This is made possible by Compose being a declarative UI framework and harnessing Kotlin’s conciseness. Custom drawing and layouts are now simple function calls instead of View subclasses with N method overrides.

Using the Ratings Table as an example:

With Views, this table consists of:

3 View classes total, with 2 requiring custom drawing for the rounded rects, and stars
~350 lines of Java, 55 lines of XML

With Compose, this table consists of:

All @Composable functions contained in the same file and language!
~210 lines of Kotlin

buffering GIF

Animations are a hailed feature of Compose for their simplicity and expressiveness. Our team is building motion features that delight our Play Store users more than ever with Compose. With Compose’s declarative nature and animations APIs, writing sequential or parallel animations has never been easier. Our team no longer fears all the corner cases of animations around cancellation and call back chaining. Lottie, a popular animation library, already provides Compose APIs that are simple to work with.

Now you might be thinking: this all sounds great, but what about library dependencies that provide Views? It's true, not all library owners have implemented Compose-based APIs, especially when we first migrated. However, Compose provides easy View interoperability with its ComposeView and AndroidView APIs. We successfully integrated with popular libraries like ExoPlayer and YouTube’s Player in this fashion.

Performance

The Play Store and Jetpack Compose teams worked closely together to make sure Compose could run as fast and be as jank-free as the View framework. Due to how Compose is bundled within the app (rather than being included as part of the Android framework), this was a tall order. Rendering individual UI components on the screen was fast, but end to end times of loading the entire Compose framework into memory for apps was expensive.

One of the largest Compose adoption performance improvements for the Play Store came from the development of Baseline Profiles. While cloud profiles help improve app startup time and have been available for some time now, they are only available for API 28+ and are not as effective for apps with frequent (weekly) release cadences. To combat this, the Play Store and Android teams worked together on Baseline Profiles: a developer-defined, bundled profile that app owners can specify. They ship with your app, are fully compatible with cloud profiles and can be defined both at the app-level of specificity and library-level (Compose adopters will get this for free!). By rolling out baseline profiles, Play Store saw a decrease in initial page rendering time on its search results page of 40%. That’s huge!

Re-using UI components is a core mechanic of what makes Compose performant for rendering, particularly in scrolling situations. Compose does its best to skip recomposition for composables that it knows can be skipped (e.g. they are immutable), but developers can also force composables to be treated as skippable if all parameters meet the @Stable annotation requirements. The Compose compiler also provides a handy guide on what is preventing specific functions from being skippable. While creating heavily re-used UI components in Play Store that were used frequently in scrolling situations, we found that unnecessary recompositions were adding up to missed frame times and thus jank. We built a Modifier to easily spot these recompositions in our debug settings as well. By applying these techniques to our UI components, we were able to reduce jank by 10-15%.

Recomposition visualization Modifier in action. Blue (no recompositions), Green (1 recomposition).

Another key component to optimizing Compose for the Play Store app was having a detailed, end-to-end migration strategy for the entire app. During initial integration experiments, we ran into the Two Stack Problem: running both Compose and View rendering within a single user session was very memory intensive, especially on lower-end devices. This cropped up both during rollouts of the code on the same page, but also when two different pages (for example, the Play Store home page and the search results page) were each on a different stack. In order to ameliorate this startup latency, it was important for us to have a concrete plan for the order and timeline of pages migrating to Compose. Additionally, we found it helpful to add short-term pre-warming of common classes as stop-gaps until the app is fully migrated over.

Compose unbundling from the Android framework has reduced the overhead in our team directly contributing to Jetpack Compose, resulting in fast turnaround times for improvements that benefit all developers. We were able to collaborate with the Jetpack Compose team and launch features like LazyList item type caching as well as move quickly on lightweight fixes like extra object allocations.

Looking Ahead

The Play Store’s adoption of Compose has been a boon for our team’s developer happiness, and a big step-up for code quality and health. All new Play Store features are built on top of this framework, and Compose has been instrumental in unlocking better velocity and smoother landings for the app. Due to the nature of our Compose migration strategy, we haven’t been able to measure things like APK size changes or build speed as closely, but all signs that we can see look very positive!

Compose is the future of Android UI development, and from the Play Store’s point of view, we couldn’t be happier about that!

Source: Android Developers Blog

Jetpack Compose 1.1 is now stable!

Posted by Florina Muntenescu, Android Developer Relations Engineer

Today, we’re releasing version 1.1 of Jetpack Compose, Android's modern, native UI toolkit, continuing to build out our roadmap. This release contains new features like improved focus handling, touch target sizing, ImageVector caching, and support for Android 12 stretch overscroll. Compose 1.1 also graduates a number of previously experimental APIs to stable and supports newer versions of Kotlin. We've already updated our samples, codelabs, and Accompanist library to work with Compose 1.1.

New stable features and APIs

Image vector caching

Compose 1.1 introduces image vector caching bringing big performance improvements. We’ve added a caching mechanism to painterResource API to cache all instances of ImageVectors that are parsed with a given resource id and theme. The cache will be invalidated on configuration changes.

Touch target sizing

With respect to Compose 1.0, Material components will expand their layout space to meet Material accessibility guidelines touch target size. For instance, a RadioButton's touch target will expand to a minimum size of 48x48dp, even if you set the RadioButton's size to be smaller. This aligns Compose Material to the same behavior of Material Design Components, providing consistent behavior if you mix Views and Compose. This change also ensures that when you create your UI using Compose Material components, minimum requirements for touch target accessibility will be met.

If you find this change breaks existing layout logic, set LocalMinimumTouchTargetEnforcement to false to disable this behavior, but please be mindful this might reduce the usability of your app, and should be used with caution.

RadioButton touch target update
Left: Compose 1.0, right: Compose 1.1

Experimental to stable APIs

Several APIs graduated from experimental to stable. Highlights include:

Animation related APIs, such as: EnterTransition, ExitTransition, some of the AnimatedVisibility APIs,
Vector related APIs: rememberVectorPainter, VectorProperty, VectorConfig, and RenderVectorGroup

New experimental APIs

We’re continuing to bring new features to Compose. Here are a few highlights:

AnimatedContent can now be saved and restored when using rememberSaveable.
LazyColumn/LazyRow item positions can be animated using Modifier.animateItemPlacement().
You can use the new BringIntoView API to send a request to parents so that they scroll to bring an item into view.

Try out the new APIs using @OptIn and give us feedback!

Note: Using Compose 1.1 requires using Kotlin 1.6.10. Check out the Compose to Kotlin Compatibility Map for more information.

Wondering what’s next? Check out our updated roadmap to see the features we’re currently thinking about and working on, such as lazy item animations, downloadable fonts, moveable content, and more!

Jetpack Compose is stable, ready for production, and continues to add the features you’ve been asking us for. We’ve been thrilled to see tens of thousands of apps start using Jetpack Compose in production already and we can’t wait to see what you’ll build!

We’re grateful for all of the bug reports and feature requests submitted to our issue tracker over the Alphas and Betas - they help us to improve Compose and build the APIs you need. Do continue providing your feedback and help us make Compose better!

Happy composing!

Source: Android Developers Blog

Android Studio Bumblebee (2021.1.1) Stable

Posted by Adarsh Fernando, Product Manager, Android

The Android Studio team has been abuzz with the stable release of Android Studio Bumblebee (2021.1.1) 🐝 and Android Gradle plugin (AGP) 7.1.0; the latest versions of Android official IDE and build system. We’ve improved functionality across a broad area of the typical developer workflow: Build and Deploy, Profiling and Inspection, and Design.

Some notable additions include a unified test execution between Android Studio and your continuous integration (CI) server ✅, convenient pairing flows to support ADB over Wi-Fi 📲, Improved Profiler tools to help you identify and analyze jank in your app 🕵️, and new ways to preview animations 🎥 and UI interactions without deploying your app to a device.

As always, this release wouldn’t be possible without the early feedback from our Preview users. So read on or watch below for further highlights and new features you can find in this stable version. If you’re ready to jump in and see for yourself, head over to the official website to download Android Studio Bumblebee (2021.1.1).

What’s in Android Studio Bumblebee (2021.1.1)

Below is a full list of new features in Android Studio Bumblebee (2021.1.1), organized by the three major themes.

Build and Deploy

New Device Manager: This new tool window in Bumblebee makes it easier to see and manage your virtual and physical test devices, and you can open it by selecting View > Tool Windows > Device Manager from the main menu bar. In the Virtual tab, create a new device, review device details, delete a device, or anything else you used to do from the now removed AVD Manager. In the Physical tab, quickly pair to a new device using ADB Wi-Fi and see details of each physical device at a glance, or quickly inspect each device’s file system using the Device File Explorer with a click of a button. Learn more about the New Device Manager in the release notes.

Device Manager

ADB over Wi-Fi: Bumblebee includes a simplified flow to connect to your Android 11 and higher devices over Wi-Fi for deployment and debugging using ADB. After you enable debugging over Wi-Fi on your device, select the Pair using Wi-Fi action in the Physical tab of the new Device Manager to open the pairing wizard. Then follow the steps provided to pair to a device connected over the same network. Learn more.

Pairing a device with ADB over Wifi

Run Instrumented Tests in Android Studio using Gradle: Have you ever run tests in Android Studio with different results than the same tests running on your CI? This can be a frustrating issue that leads to lost productivity. To resolve this issue, we’ve introduced a new test runner to Android Gradle plugin (AGP) 7.1.0 that Android Studio Bumblebee uses by default when running instrumentation tests, so all your tests run through a unified test runner. This is a similar improvement to Android Studio Arctic Fox, where we started running all unit tests via Gradle by default. And, similarly, this improvement doesn’t require you to change how you write or run your tests!

Using different runners lead to inconsistent results

Android Studio now runs instrumentation tests via Gradle

Android Gradle Plugin Upgrade Assistant now updates API usage: Originally introduced in Android Studio 4.2, the AGP Upgrade Assistant helped users update their projects to the latest version, and improvements in Arctic Fox provided a new UI with the ability to review and select the upgrade version and steps. In Bumblebee, the Upgrade Assistant now also checks for and offers to update your DSL to help you avoid using deprecated APIs before they are deleted. For more information see the Android Gradle Plugin DSL/API migration timeline.

Non-Transitive R classes on for new projects: Android Studio Arctic Fox introduced new refactoring tools to help you use non-transitive R classes to enable faster builds for applications with multiple modules. When creating new projects using Bumblebee, the IDE configures your project to use non-transitive R classes, by default. While this does bring performance improvements, you now have to refer to R classes by their proper package name, and not by the package names of their parent modules, as they will no longer resolve transitively. For more information see Use non-transitive R classes.

Emulator tool window enabled by default: Introduced in Android Studio 4.1, the Emulator launches within an Android Studio tool window and allows you to deploy and interact with virtual Android devices while fully remaining within the context of the IDE. The changes ads an improved UX for extended controls and snapshot management. For more information see Run the Android Emulator directly in Android Studio.

Apple Silicon Support Update - For those using macOS on Apple Silicon (arm64) hardware, Android Studio Arctic Fox and the Android Emulator have supported this new architecture since last year. However, with this release, we have now updated the Android SDK platform tools v32.0.0 (which includes ADB and fastboot) and build tools v32.1.0 (which includes aapt) to be universal binaries so that your Android developer tools no longer need the Rosetta binary translator to run. Based on community feedback, those developers on this hardware platform have seen notable performance improvements. See release notes.

Profile and Inspect

Jank detection track in Profilers: When profiling your app using devices running Android 11 (API level 30) or higher, the CPU profiler now shows a new group of tracks that illustrate the stages of each frame under Frame Lifecycle: Application, Wait for GPU, Composition and Frames on display. Each track labels the frames with a frame number and color-codes the rectangle to make it easy for you to visualize where a particular frame is in its lifecycle, along with guides you can toggle to compare with Vsync events. You can use this data to understand where Jank might occur in your app and investigate the root causes. In the Analysis panel, there is now a Frames tab, which conveniently summarizes rendering information for all frames. For more information, see UI jank detection.

Detailed frame lifecycle information in the CPU Profiler

Profileable app profiling support in Studio Profilers: When profiling your app, it’s important to generate accurate data with the version of your app that most closely resembles what your users will install. To do so, you can now include the <profileable> property in your app’s manifest to profile apps that are not debuggable, as shown below.

<profileable android:shell="true"/>

Profileable is a manifest configuration introduced in Android 10, and is available for CPU and Memory profiling tasks. Using the profileable flag instead of the debuggable flag has the key advantage of lower overhead for performance measurement; however, certain profiling features are not available for Profileable builds, such as the Event timeline, API initiated CPU profiling, heap dumps, or live location recordings. For more information, see Profileable applications.
Inspect Jobs, Alarms, and Wakelocks: The Background Task Inspector has been expanded to allow you to inspect Jobs, Alarms, and Wakelocks. You can see live information on how these background tasks are being scheduled, and see detailed information about their execution, similar to how you can inspect Workers. Additionally, when inspecting Workers, you can track and inspect Jobs that your Workers schedule for you. If you used to use the Energy Profiler in previous versions of the IDE, you should now navigate to View > Tool Windows > App Inspection from the menu bar and select the Background Task Inspector to inspect Jobs, Alarms, and Wakelocks.

Inspect Jobs, Alarms, and Wakelocks in the Background Task Inspector

Network Inspection: The Network Profiler has now migrated to the App Inspection tool window, to allow for a lighter-weight experience for inspecting network traffic in your app. The look and feel of the Network Profiler has been maintained and works with any debuggable app on devices running API level 26 and higher. To use the new inspector, select View > Tool Windows > App Inspection from the menu bar and select the Network Inspector. For more information, see Inspect network traffic with the Network Inspector.

Capture Layout Inspector snapshots: You can now capture snapshots of your app’s layout hierarchy to save, share, or inspect later. Snapshots capture the data you would typically see when using the Layout Inspector, including a detailed 3D rendering of your layout, the component tree of your View, Compose, or hybrid layout, and detailed attributes for each component of your UI. When inspecting the layout of a live running app, click Export snapshot from the Layout Inspector toolbar and save the snapshot with an *.li extension. You can then load a Layout Inspector snapshot by selecting File > Open from the main menu bar, and opening a *.li file. The snapshot appears in a tab in the Editor window, so that you can easily compare it with your running app. Learn more at Capture layout hierarchy snapshots.

Support for Compose semantics in the Layout Inspector: In Compose, Semantics describe your UI in an alternative manner that is understandable for Accessibility services and for the Testing framework. In Android Studio Bumblebee, you can now use the Layout Inspector to inspect semantic information in your Compose layouts. When selecting a Compose node, use the Attributes window to check whether it declares semantic information directly, merges semantics from its children, or both. To quickly identify which nodes include semantics, either declared or merged, use select the View options dropdown in the Component Tree window and select Highlight Semantics Layers.

Design

Interactive Preview: Android Studio Arctic Fox launched with support to statically preview your composable functions in the Design / Split window of the Editor. In Bumblebee, we’ve expanded functionality to allow you to interact with certain components of your Compose layouts, to validate behavior without building and deploying the full app to a running device! To get started, navigate to a previewable compose function and click Start Interactive Mode in the Design / Split window. For more information see Interactive mode.

Interact with the Compose Preview to validate behavior

Animated Vector Drawables Preview: The Preview window is now also available when viewing vector drawables. When viewing a static drawable, you can use the preview window to change background options between “None”, “White”, “Black”, “Checkedered”, to view your drawable against different conditions. Animated drawables also provide the option to preview the animation at different speeds as well as backgrounds, to help you test animations before using them in your app. To learn more, see Animated Vector Drawables (AVD) preview.

Preview your animated vector drawables

Updated Device picker for design tools: To simplify designing your app for the diverse number of Android devices, we’ve updated the device picker in various design tool windows, such as Layout Editor and Layout Validation, with reference devices that reflect popular sizes of each device form factor. From phones to tablets, and Wear devices to Android TVs, it’s now easier to preview, validate, or edit your layout on screen sizes that are most representative of popular real-world devices. To learn more, see Change the preview appearance.

To recap, Android Studio Bumblebee (2021.1.1) includes these new enhancements & features:

Build and Deploy

Run Instrumented Tests in Android Studio using Gradle
Android Gradle Plugin Upgrade Assistant now updates API usage
Non-Transitive R classes on for new projects
New Device Manager
ADB over Wi-Fi
Emulator tool window enabled by default
Apple Silicon Support Update

Profile and Inspect

Jank detection track in Profilers
Profileable app profiling support in Studio Profilers
Inspect Jobs, Alarms, and Wakelocks in the Background task Inspector
Capture Layout Inspector snapshots
Support for Compose semantics in the Layout Inspector

Design

Interactive Preview
Animated Vector Drawables Preview
Updated Device picker for design tools

Source: Android Developers Blog

12L and new Android APIs and tools for large screens

Posted by Dave Burke, VP of Engineering

There are over a quarter billion large screen devices running Android across tablets, foldables, and ChromeOS devices. In just the last 12 months we’ve seen nearly 100 million new Android tablet activations–a 20% year-over-year growth, while ChromeOS, now the fastest growing desktop platform, grew by 92%. We’ve also seen Foldable devices on the rise, with year on year growth of over 265%! All told, there are over 250 million active large screen devices running Android. With all of the momentum, we’re continuing to invest in making Android an even better OS on these devices, for users and developers.

So today at Android Dev Summit, we announced a feature drop for Android 12 that is purpose-built for large screens, we’re calling it 12L, along with new APIs, tools, and guidance to make it easier to build for large screens. We also talked about changes we’re making to Google Play to help users discover your large-screen optimized apps more easily. Read on to see what’s new for large screens on Android!

Previewing 12L: A feature drop for large screens

Today we're bringing you a developer preview of 12L, our upcoming feature drop that makes Android 12 even better on large screens. With the preview, you can try the new large screen features, optimize your apps, and let us know your feedback.

In 12L we’ve refined the UI on large screens across notifications, quick settings, lockscreen, overview, home screen, and more. For example, on screens above 600dp, the notification shade, lockscreen, and other system surfaces use a new two-column layout to take advantage of the screen area. System apps are also optimized.

image shows a phone with two-column layouts

Two-column layouts show more and are easier to use

We’ve also made multitasking more powerful and intuitive - 12L includes a new taskbar on large screens that lets users instantly switch to favorite apps on the fly. The taskbar also makes split-screen mode more discoverable than ever - just drag-and-drop from the taskbar to run an app in split-screen mode. To make split-screen mode a better experience in Android 12 and later, we’re helping users by automatically enabling all apps to enter split screen mode, regardless whether the apps are resizable.

GIF image shows maps and web brower on the screen at the same time

Drag and drop apps into split-screen mode

Last, we’ve improved compatibility mode with visual and stability improvements to offer a better letterboxing experience for users and help apps look better by default. We’ve made letterboxing easily customizable by device manufacturers, who can now set custom letterbox colors or treatments, adjust the position of the inset window, apply custom rounded corners, and more.

We plan to release the 12L feature drop early next year, in time for the next wave of Android 12 tablets and foldables. We’re already working with our OEM partners to bring these features to their large screen devices - watch for the developer preview of 12L coming soon to the Lenovo P12 Pro. With the features coming to devices in the few months ahead, now is a great time to optimize your apps for large screens.

For developers, we highly recommend checking out how your apps work in split screen mode with windows of various sizes. If you haven’t optimized your app yet, see how it looks in different orientations and try the new compatibility mode changes if they apply. Along with the large screen features, 12L also includes a handful of new APIs for developers, along with a new API level. We’ve been careful not to introduce any breaking changes for your apps, so we won’t require apps to target 12L to meet Google Play requirements.

To get started with 12L, download the 12L Android Emulator system images and tools from the latest preview release of Android Studio. Review the features and changes to learn about areas to test in your apps, and see preview overview for the timeline and release details. You can report issues and requests here, and as always, we appreciate your feedback!

12L is for phones, too, but since most of the new features won’t be visible on smaller screens, for now we’re keeping the focus on tablets, foldables, and ChromeOS devices. Later in the preview we plan to open up Android Beta enrollments for Pixel devices. For details, visit developer.android.com/12L.

Making it easier to build for large screens

It's time to start designing fully adaptive apps to fit any screen, and now we're making it even easier. To help you get ready for these changes in the OS and Play, along with the developer preview we're releasing updates to our APIs, tools and guidance.

Design with large screen patterns in mind

The first step to supporting adaptive UI is designing your app to behave nicely on both a small and a larger screen. We’ve been working on new Material Design guidance that will help you scale your app’s UI across all screens. The guidance covers common layout patterns prevalent in the ecosystem that will help inspire and kick-start your efforts.

Adaptive UI patterns in the Material Design guidelines

Build responsive UIs with new navigation components

To provide the best possible navigation experience to your users, you should provide a navigation UI that is tailored to the Window Size Class of the user’s device. The recommended navigation patterns include using a navigation bar for compact screens and a navigation rail for medium-width device classes and larger (600dp+). For expanded-width devices, there are several ideas on larger screen layouts within our newly released Material Design guidance such as a List/Detail structure that can be implemented, using SlidingPaneLayout. Check out our guidance on how to implement navigation for adaptive UIs in Views and Compose.

While updating the navigation pattern and using a SlidingPaneLayout is a great way to apply a large screen optimized layout to an existing application with fragments, we know many of you have applications based on multiple activities. For those apps, the new activity embedding APIs released in Jetpack WindowManager 1.0 beta 03 make it easy to support new UI paradigms, such as a TwoPane view. We’re working on updating SlidingPaneLayout to support those APIs - look for an update in the coming months.

Use Compose to make it easier to respond to screen changes

Jetpack Compose makes it easier to build for large screens and diverse layouts. If you’re starting to adopt Compose, it’s a great time to optimize for large screens along the way.

Compose is a declarative UI toolkit; all UI is described in code, and it is easy to make decisions at runtime of how it should adapt to the available size. This makes Compose especially great for developing adaptive UI, as it is very easy to handle UI changes across different screen sizes or components. The Build adaptive layouts in Compose guide covers the basics of what you need to know.

Use WindowManager APIs to build responsive UIs

The Jetpack WindowManger library provides a backward-compatible way to work with windows in your app and build responsive UI for all devices. Here’s what’s new.

Activity embedding

Activity embedding lets you take advantage of the extra display area of large screens by showing multiple activities at once, such as for the List-Detail pattern, and it requires little or no refactoring of your app. You determine how your app displays its activities—side by side or stacked—by creating an XML configuration file or making Jetpack WindowManager API calls. The system handles the rest, determining the presentation based on the configuration you’ve created.

Activity embedding works seamlessly on foldable devices, stacking and unstacking activities as the device folds and unfolds. If your app uses multiple activities, activity embedding can enhance your user experience on large screen devices. Try the activity embedding APIs in Jetpack WindowManager 1.0 Beta 03 and later releases. More here.

Activity embedding with Jetpack WindowManager

Use Window size classes to help detect the size of your window

Window Size Classes are a set of opinionated viewport breakpoints for you to design, develop and test resizable application layouts against. The Window Size Class breakpoints have been split into three categories: compact, medium, and expanded. They have been designed specifically to balance layout simplicity with the flexibility to optimize your app for the most unique use cases, while representing a large proportion of devices in the ecosystem. The WindowSizeClass APIs will be coming soon in Jetpack WindowManager 1.1 and will make it easier to build responsive UIs. More here.

Image compares the width of Window Size Classes by showing compact, medium, and expanded views

Window Size Classes in Jetpack WindowManager

Make your app fold-aware

WindowManager also provides a common API surface for different window features, like folds and hinges. When your app is fold aware, the content in the window can be adapted to avoid folds and hinges, or to take advantage of them and use them as natural separators. Learn how you can make your app fold aware in this guide.

Building and testing for large screens with Android Studio

Reference Devices

Since Android apps should be built to respond and adapt to all devices and categories, we’re introducing Reference Devices across Android Studio in many tools where you design, develop and test UI and layout. The four reference devices represent phones, large foldable inner displays, tablets, and desktops. We’ve designed these after analyzing market data to represent either popular devices or rapidly growing segments. They also enable you to ensure your app works across popular breakpoint combinations with the new WindowSizeClass breakpoints, to ensure your app covers as many use cases as possible.

Reference Device definitions

Layout validation

If you’re not sure where to get started adapting your UI for large screens, the first thing you can do is use new tools to identify potential issues impacting large screen devices. In Android Studio Chipmunk, we’re working on a new visual linting tool to proactively surface UI warnings and suggestions in Layout Validation, including which reference devices are impacted.

Layout validation tool with Reference Device classes

Resizable emulator

To test your app at runtime, we can use the new resizable emulator configuration that comes with Android Studio Chipmunk. The resizable emulator lets you quickly toggle between the four reference devices - phone, foldable, tablet, and desktop. This makes it easier to validate your layout at design time and test the behavior at runtime, both using the same reference devices. To create a new Resizable emulator, use the Device Manager in Android Studio to create a new Virtual Device and select the Resizable device definition with the Android 12L (Sv2) system image.

Resizable Android Emulator

Changes to Google Play on large screens

To make it easier for people to find the best app experiences on their tablets, foldables, and ChromeOS devices, we're making changes in Play to highlight apps that are optimized for their devices.

We’re adding new checks to assess each app’s quality against our large screen app quality guidelines to ensure that we surface the best possible apps on those devices. For apps that are not optimized for large screens, we’ll start warning large screen users with a notice on the app’s Play Store listing page.

We'll also be introducing large screen specific app ratings, as announced earlier this year, so users will be able to rate how your app works on their large screen devices. These changes are coming next year, so we're giving you advanced notice to get your apps ready!

Also, make sure to check out our post that highlights how we are evolving our business model to address developer needs in Google Play.

Learn more!

To help you get started with building for large screens and foldables, no matter whether you’re using Views or Compose, we’ve got you covered! We’re launching new and updated guidance on how to support different screen sizes both in a new and in an existing app, how to implement navigation for both Views and Compose, how to take advantage of foldable devices and more. Check them out in the large screens guides section for Views support or in the Compose guides section.

Nothing speaks louder than code - we updated the following samples to support responsive UIs:

For some hands-on work, check out our Support foldable and dual-screen devices with Jetpack WindowManager updated codelab.

Source: Android Developers Blog

Answering your top questions on Android Game Development Kit

Posted by Wayne Lu, Technical Lead Manager, Android DevRel

We launched the Android Game Development Kit (AGDK) in July, and have collected some top questions from developers - ranging from AGDK libraries and tools, optimizing memory in Android, and implementing graphics.

AGDK and game engines

Firstly, we’ve heard questions from early, rising game developers on how to use our set of AGDK libraries and tools. We have the following recommendations depending on your setup:

For game developers using popular game engines such as Defold, Godot, Unity, or Unreal - you can follow our guides to learn how to develop apps on Android. Using these game engines lets you focus on building gameplay instead of the entire technology stack.
If you're using Unreal Engine and targeting multiple platforms such as PC or consoles, Android Game Development Extension (AGDE) may be a great addition to your workflow.
We also support developers who want to customize and write their own game engine - you can learn more about this with our C or C++ documentation.

After choosing your game engine and workflow, you should look into our tools such as the Android Studio Profiler to inspect your game, Android GPU Inspector to profile graphics and Android Performance Tuner to optimize frame rates and loading times.

Game Mode API and Interventions

Following this, we’ve received questions on developing for Android 12. While you don’t have to do anything special for your game to run on Android 12, we’ve introduced Game Mode API and interventions to help players customise their gaming experience.

Read more about the Game Mode API, and find out how to optimize your game for the best performance or longest battery life when the user selects the corresponding game mode.
Learn about the Game Mode interventions - these are set by original equipment manufacturers (OEMs), to improve the performance of games that are no longer being updated by developers. For example: WindowManager backbuffer resize to reduce a device's GPU load.

Memory Access in Android

Secondly, you’ve asked us how memory access works in Android game development versus Windows. In short, here are a couple of pointers:

Games need to share memory with the system. Some devices have less available memory than others, so testing is needed to check for low memory issues on a range of supported devices. Testing should be done on devices with typical apps that a user would have installed (i.e. not a clean device).
The amount of memory a game can allocate depends on various factors such as the amount of physical memory, the number of dirty pages, and the amount of total zRam (for compressed swapping)
Symptoms of low memory can be: onTrimMemory() calls, memory thrashing, or termination of the game by the Low Memory Killer. Use bugreport logs to check if the game was killed by the Low Memory Killer, or on Android 11 and later check the ApplicationExitInfo to see if the game was terminated because of REASON_LOW_MEMORY.
Avoid memory thrashing: this occurs when there’s low but insufficient memory to kill the game. You can detect this via system tracing, and should reduce the overall memory footprint to avoid this issue.
Use the Android Profiler and other tools to inspect your memory usage.

Implementing Graphics in Android

Thirdly, we’ve received questions about implementing graphics in Android. You have the following options: OpenGL ES or Vulkan graphics APIs:

Learn how to configure OpenGL ES graphics for your C++ game engine by initializing variables, rendering with the game loop, scenes and objects.
Read our Vulkan guides to learn how to draw a cube, compile shaders, setup validation layers, and other best practices.

Check out the Q&A video to view the top questions on AGDK and visit g.co/android/AGDK for our latest resources for Android game development.

Source: Android Developers Blog

Working Towards Android App Excellence

Posted by Jacob Lehrbaum Director of Developer Relations, Android

illustration of freckled hand over mobile phone with graphs

Great app experiences are great for business. In fact, nearly three-quarters of Android app users who leave a 5 star review on Google Play mention the quality of their experience with the app¹; its speed, design, and usability. At Google, we want to help all developers achieve app excellence, and in turn help you drive user acquisition, retention, and monetization.

So what is “app excellence”? This may sound aspirational, but it is within reach for many apps. It starts with a laser focus on the user, and more specifically, with intuitive user experiences that get people to the main functionality of your app as quickly as possible — but that is just the beginning. Excellent apps are consistent across all of their screens and experiences. They perform well, no matter the device used. App excellence is achievable when all of the stakeholders who influence your app are invested in the experience of using your app.

One of the blockers that gets in the way of app excellence is shared or unclear accountability. Some of the primary measures of app quality, such as crashes and load times, are often seen as the responsibility of one group in the company, such as the engineering team. However, when we talk to best-in-class organizations² about how they achieve app quality, it is clear that taking a cross-functional approach is key, with engineering, design, product, and business teams working toward a common goal.

So what are some internal best practices behind app excellence?

Make app quality a cross-organizational focus — not just an engineering concern

It’s a way easier conversation for me at the business end because I can say “these competitors’ apps are faster than ours; we need to reduce our load time down from 5 seconds to 4 seconds”.

Software engineer, x-platform app

App excellence helps drive business performance. New features are great, but if they slow down app start-up times or take up too much device space, people will eventually use your app less often or even delete it. Engineers who have built a company-wide focus on quality have often done so by quantifying the impact of quality issues on business performance, through:

Case studies showing the impact of responsiveness, APK size, start-up time, and memory usage on business KPIs. Here you can find practical case studies showcasing how developers such as Headspace and Duolingo achieved app excellence.
Benchmarking against competitor apps. Check out peer benchmarks and other metrics on the Google Play Console.

Organize teams around features and/or app user journey stages

Companies that organize teams around features — or stages in the user journey — are more likely to deliver consistent experiences across each operating system they support, bring new apps or features to market faster, and deliver a better app experience for all their customers. These teams are often cross-functional groups that span engineering, marketing, ux, and product — and are responsible for the success of a feature or user journey stage³ across all devices and platforms. In addition to better experiences and feature parity, this structure enables alignment of goals across functional areas while reducing silos, and it also helps teams hyper-focus on addressing specific objectives.

Squads focused on business objectives heighten focus on the user.

Use the same devices your customers use

If a majority of your users are on a specific type of device, you can build empathy for their experience if you use the same phone, tablet or smart watch as your primary device. This is especially relevant for senior leadership in your organization who make decisions that impact the day-to-day experience of millions of users. For example, Duolingo has built this into their company DNA. Every Duolingo employee — including their CEO — either uses exclusively or has access to an entry level Android device to reflect a significant portion of their user base.

A user-centric approach to quality and app excellence is essential to business growth. If you are interested in learning how to achieve app excellence, read our case studies with practical tips, and sign up to attend our App Excellence Summit by visiting the Android app excellence webpage.

In subsequent blog posts, we will dig deep into two drivers of excellent app experiences: app performance and how it is linked to user behavior, and creating seamless user experiences across devices. Sign up to the Android developer newsletter here to be notified of the next installment, and get news and insights from the Android team.

Notes

Internal Google Play data, 2021. ↩
Google App Quality Research, 2021 ↩
The series of steps each user takes as they interact with your app is referred to as the “user journey.” Examples of user journey stages include installs, onboarding, engagement, and retention ↩