Tag Archives: Jetpack Compose

Jetpack Compose is now 1.0: announcing Android’s modern toolkit for building native UI

Posted by Anna-Chiara Bellini, Product Manager, Nick Butcher, Developer Relations

Today, we're launching version 1.0 of Jetpack Compose, Android's modern, native UI toolkit to help you build better apps faster. It's stable, and ready for you to adopt in production. We have been developing Compose in the open with feedback and participation from the Android community for the last two years. As we reach 1.0, there are already over 2000 apps in the Play Store using Compose - in fact, the Play Store app itself uses Compose! But that’s not all, we have been working with a number of top app developers and their feedback and support has helped us make the 1.0 release even stronger. Square, for instance, told us that by using Compose, they can “focus on things that are unique to Square and their UI infrastructure, rather than solving the broader issue of building a declarative UI framework”. Monzo said Compose allows them to “build higher quality screens more quickly”. And Twitter summed it up nicely: “We love it! ❤️

We designed Compose to make it faster and easier to build native Android apps. With a fully declarative approach, you just describe your UI, and Compose takes care of the rest. As app state changes, your UI automatically updates, making it a lot simpler to build UI quickly. Intuitive Kotlin APIs help you build beautiful apps with way less code, and native access to all existing Android code means you can adopt at your own pace. Powerful layout APIs and code-driven UI make it easy to support different form factors, like tablets and foldables, and Compose support is coming for WearOS, Homescreen Widgets, and more!

This 1.0 release is ready for use in production, offering key features that you need:

  • Interoperable: Compose is built to interoperate with your existing app. You can embed compose UIs within Views or Views within Compose. You can add as little as a single button to a screen, or keep that custom view you’ve created in a now Compose screen.
  • Jetpack Integration: Compose is built to integrate with the Jetpack libraries you already know and love. With integration with Navigation, Paging, LiveData (or Flow/RxJava), ViewModel and Hilt, Compose works with your existing architecture.
  • Material: Compose offers an implementation of Material Design components and theming, making it easy to build beautiful apps that reflect your brand. The Material theming system is easier to understand and trace, without having to consult multiple XML files.
  • Lists: Compose’s Lazy components offer a simple, succinct but powerful way to efficiently display lists of data, with minimal boilerplate.
  • Animation: Compose’s simple and coherent animation APIs make it far easier to delight your app’s users.


New Tools

The fully declarative approach in Jetpack Compose radically changes how you develop UI. To support new workflows and a different way of thinking, we are delivering new tools, designed specifically for Compose, and adding support for Compose to some of our existing tooling.

Compose Preview

The new Compose Preview, available in Android Studio Arctic Fox allows you to see your Composables in different states, light and dark theme, or different font scalings, all at the same time, making component development easier, without having to deploy a whole app to your device. Enhanced with live editing of literals, you can see updates without recompiling your project.


Deploy Preview

If you ever wished to be able to test parts of the UI on a device, without having to navigate through your app to the screen you’re working on, you will like the new Deploy Preview: just create a preview for your Composable, and deploy it on your device for fast iteration.

Compose support in Layout Inspector

Layout Inspector adds support for Composables, so that you can confidently mix Compose with existing Views.

Read more about Compose support in Android Studio Arctic Fox, here.

Sharing our roadmap for Compose

Adopting any new framework requires evaluation, especially something as far reaching as a new UI Toolkit. To help you to make an informed decision whether it’s the right time for you we’re publishing a public roadmap to share our plans to continue to build out Jetpack Compose.





Learning Compose

To help you get composing, we’ve prepared an extensive set of resources for you and your team:


There’s a lot to learn! The Jetpack Compose Pathway provides a step-by-step journey through key codelabs, videos and docs to help guide you.

Enjoy composing!

We really believe that Jetpack Compose is a huge leap forward, making it so much faster and easier to build great UIs; we can’t wait to see what you build with it. Now that Compose is stable at 1.0, it’s time to get started; there’s nothing better than getting right to the code. Happy Composing!

What’s new for Android developers at Google I/O

Cross-posted on the Android Developers blog by Karen Ng, Director, Product Management & Jacob Lehrbaum, Director of Developer Relations, Android & Play

As Android developers, we are all driven by building experiences that delight people around the world. And with people depending on your apps more than ever, expectations are higher and your jobs as developers aren’t getting easier. Today, at Google I/O, we covered a few ways that we’re trying to help out, whether it be through Android 12 - one of the biggest design changes ever, Jetpack, Jetpack Compose, Android Studio, and Kotlin to help you build beautiful high quality apps. We’re also helping when it comes to extending your apps wherever your users go, like through wearables and larger-screened devices. You can watch the full Developer Keynote, but here are a few highlights:

Android 12: one of the biggest design updates ever.

The first Beta of Android 12 just started rolling out, and it’s packed with lots of cool stuff. From new user safety features like permissions for bluetooth and approximate location, enhancements to performance like expedited jobs and start up animations, to delightful experiences with more interactive widgets and stretch overscrolling, this release is one of the biggest design updates to Android ever. You can read more about what’s in Android 12 Beta 1 here, so you can start preparing your apps for the consumer release coming out later this year. Download the Beta and try it with your apps today!

Android 12 visual

Jetpack Compose: get ready for 1.0 in July!

For the last few years, we’ve been hard at work modernizing the Android development experience, listening to your feedback to keep the openness–a hallmark of Android, but becoming more opinionated about the right way to do things. You can see this throughout, from Android Studio, a performant IDE that can keep up with you, to Kotlin, a programming language that enables you to do more with less code, to Jetpack libraries that solve the hardest problems on mobile with backward compatibility.

The next step in this offering is Jetpack Compose - our modern UI toolkit to easily build beautiful apps for all Android devices. We announced Compose here at Google I/O two years ago and since then have been building it in the open, listening to your feedback to make sure we got it right. With the Compose Beta earlier this year, developers around the world have created some truly beautiful, innovative experiences in half the time, and the response to the #AndroidDevChallenge blew our socks off!

With the forthcoming update of Material You (which you can read more about here), we’ll be adding new Material components as well as further support for building for large screens, making it fast and easy to build a gorgeous UI. We’re pressure testing the final bits in Compose and will release 1.0 Stable in July—so get ready!

Android Studio Arctic Fox: Design, Devices, & Developer Productivity!

Android Studio Arctic Fox (2020.3.1) Beta, the latest release of the official powerful Android IDE, is out today to help you build quality apps easier and faster. We have delivered and updated the suite of tools to empower three major themes: accelerate your UI design, extend your app to new devices, and boost your developer productivity. With this latest release you can create modern UIs with Compose tooling, see test results across multiple devices, and optimize debugging databases and background tasks with the App Inspector. We’re also making your apps more accessible with the Accessibility Scanner and more performant with Memory Profiler. And for faster build speeds, we have the Android Gradle plugin 7.0, new DSL, and variant APIs. You can learn more about the Android Studio updates here.

Android Studio Arctic Fox

Kotlin: the most used language by professional Android devs

Kotlin is now the most used primary language by professional Android developers according to our recent surveys; in fact, over 1.2M apps in the Play Store use Kotlin, including 80% of the top 1000 apps. And here at Google, we love it too: 70+ Google apps like Drive, Home, Maps and Play use Kotlin. And with a brand-new native solution to annotation processing for Kotlin built from the ground up, Kotlin Symbol Processing is available today, a powerful and yet simple API for parsing Kotlin code directly, showing speeds up to 2x faster with libraries like Room.

Android Jetpack: write features, not boilerplate

With Android Jetpack, we built a suite of libraries to help reduce boilerplate code so you can focus on the code you care about. Over 84% of the top 10,000 apps are now using a Jetpack library. And today, we’re unpacking some new releases for Jetpack, including Jetpack Macrobenchmark (Alpha) to capture large interactions that affect your app startup and jank before your app is released, as well as a new Kotlin Coroutines API for persisting data more efficiently via Jetpack DataStore (Beta). You can read about all the updates in Android Jetpack here.

Now is the time: a big step for Wear

The best thing about modern Android development is that these tools have been purpose built to help make it easy for you to build for the next era of Android, which is all about enabling devices connected to your phone–TVs, cars, watches, tablets–to work better together.

Starting today, we take a huge step forward with wearables. First, we introduced a unified platform built jointly with Samsung, combining the best of Wear and Tizen. Second, we shared a new consumer experience with revamped Google apps. And third, a world-class health and fitness service from Fitbit is coming to the platform. As an Android developer, it means you’ll have more reach, and you’ll be able to use all of your existing skills, tools, and APIs that make your mobile apps great, to build for a single wearables platform used by people all over the world.

Whether it’s new Jetpack APIs for Wear tailored for small screens and designed to optimize battery life, to the Jetpack Tiles API, so you can create a custom Tile for all the devices in the Wear ecosystem, there are a number of new features to help you build on Wear. And with a new set of APIs for Health and Fitness, created in collaboration with Samsung, data collection from sensors and metrics computation is streamlined, consistent, and accurate–like heart rate to calories to daily distance–from one trusted source. All this comes together in new tooling, with the release of Android Studio Arctic Fox Beta, like easier pairing to test apps, and even a virtual heart rate sensor in the emulator. And when your app is ready, users will have a much easier time discovering the world of Wear apps on Google Play, with some big updates to discoverability. You can read more about all of the Wear updates here.

Tapping the momentum of larger screens, like tablets, Chrome OS and foldables

When it comes to larger screens -- tablets, foldables, and Chrome OS laptops-- there is huge momentum. People are increasingly relying on large screen devices to stay connected with family and friends, go to school, or work remotely. In fact, there are over 250 million active large screen Android devices. Last year, Chrome OS grew +92% year over year–5 times the rate of the PC market, making Chrome OS the fastest growing and the second-most popular desktop OS. To help you take advantage of this momentum, we’re giving you APIs and tools to make optimizing that experience easier: like having your content resize automatically to more space by using SlidingpaneLayout 1.2.0 and a new vertical navigation rail component, Max widths on components to avoid stretched UIs, as well as updates to the platform, Chrome OS, and Jetpack windowmanager, so apps work better by default. You can learn more here.

Google Duo's optimized experience for foldable devices

Google Duo's optimized experience for foldable devices

This is just a taste of some of the new ways we’re making it easier for you to build high quality Android apps. Later today, we’ll be releasing more than 20 technical sessions on Android and Play, covering a wide range of topics such as background tasks, privacy, and Machine Learning on Android, or the top 12 tips to get you ready for Android 12. If building for cars, TVs, and wearables is your thing, we got that covered, too. You can find all these sessions - and more - on the I/O website. Beyond the sessions and news, there’s a number of fun ways to virtually connect with Googlers and other developers at this year’s Google I/O. You can check out the Android dome in I/O Adventure, where you can see new blog posts, videos, codelabs, and more. Maybe even test out your Jetpack Compose skills or take a virtual tour of the cars inside our dome!

What’s new for Android developers at Google I/O

Posted by Karen Ng, Director, Product Management & Jacob Lehrbaum, Director of Developer Relations, Android & Play

As Android developers, we are all driven by building experiences that delight people around the world. And with people depending on your apps more than ever, expectations are higher and your jobs as developers aren’t getting easier. Today, at Google I/O, we covered a few ways that we’re trying to help out, whether it be through Android 12 - one of the biggest design changes ever, Jetpack, Jetpack Compose, Android Studio, and Kotlin to help you build beautiful high quality apps. We’re also helping when it comes to extending your apps wherever your users go, like through wearables and larger-screened devices. You can watch the full Developer Keynote, but here are a few highlights:

Android 12: one of the biggest design updates ever.

The first Beta of Android 12 just started rolling out, and it’s packed with lots of cool stuff. From new user safety features like permissions for bluetooth and approximate location, enhancements to performance like expedited jobs and start up animations, to delightful experiences with more interactive widgets and stretch overscrolling, this release is one of the biggest design updates to Android ever. You can read more about what’s in Android 12 Beta 1 here, so you can start preparing your apps for the consumer release coming out later this year. Download the Beta and try it with your apps today!

Android 12 visual

Jetpack Compose: get ready for 1.0 in July!

For the last few years, we’ve been hard at work modernizing the Android development experience, listening to your feedback to keep the openness–a hallmark of Android, but becoming more opinionated about the right way to do things. You can see this throughout, from Android Studio, a performant IDE that can keep up with you, to Kotlin, a programming language that enables you to do more with less code, to Jetpack libraries that solve the hardest problems on mobile with backward compatibility.

The next step in this offering is Jetpack Compose - our modern UI toolkit to easily build beautiful apps for all Android devices. We announced Compose here at Google I/O two years ago and since then have been building it in the open, listening to your feedback to make sure we got it right. With the Compose Beta earlier this year, developers around the world have created some truly beautiful, innovative experiences in half the time, and the response to the #AndroidDevChallenge blew our socks off!

With the forthcoming update of Material You (which you can read more about here), we’ll be adding new Material components as well as further support for building for large screens, making it fast and easy to build a gorgeous UI. We’re pressure testing the final bits in Compose and will release 1.0 Stable in July—so get ready!

Android Studio Arctic Fox: Design, Devices, & Developer Productivity!

Android Studio Arctic Fox (2020.3.1) Beta, the latest release of the official powerful Android IDE, is out today to help you build quality apps easier and faster. We have delivered and updated the suite of tools to empower three major themes: accelerate your UI design, extend your app to new devices, and boost your developer productivity. With this latest release you can create modern UIs with Compose tooling, see test results across multiple devices, and optimize debugging databases and background tasks with the App Inspector. We’re also making your apps more accessible with the Accessibility Scanner and more performant with Memory Profiler. And for faster build speeds, we have the Android Gradle plugin 7.0, new DSL, and variant APIs. You can learn more about the Android Studio updates here.

Android Studio Arctic Fox

Kotlin: the most used language by professional Android devs

Kotlin is now the most used primary language by professional Android developers according to our recent surveys; in fact, over 1.2M apps in the Play Store use Kotlin, including 80% of the top 1000 apps. And here at Google, we love it too: 70+ Google apps like Drive, Home, Maps and Play use Kotlin. And with a brand-new native solution to annotation processing for Kotlin built from the ground up, Kotlin Symbol Processing is available today, a powerful and yet simple API for parsing Kotlin code directly, showing speeds up to 2x faster with libraries like Room.

Android Jetpack: write features, not boilerplate

With Android Jetpack, we built a suite of libraries to help reduce boilerplate code so you can focus on the code you care about. Over 84% of the top 10,000 apps are now using a Jetpack library. And today, we’re unpacking some new releases for Jetpack, including Jetpack Macrobenchmark (Alpha) to capture large interactions that affect your app startup and jank before your app is released, as well as a new Kotlin Coroutines API for persisting data more efficiently via Jetpack DataStore (Beta). You can read about all the updates in Android Jetpack here.

Now is the time: a big step for Wear

The best thing about modern Android development is that these tools have been purpose built to help make it easy for you to build for the next era of Android, which is all about enabling devices connected to your phone–TVs, cars, watches, tablets–to work better together.

Starting today, we take a huge step forward with wearables. First, we introduced a unified platform built jointly with Samsung, combining the best of Wear and Tizen. Second, we shared a new consumer experience with revamped Google apps. And third, a world-class health and fitness service from Fitbit is coming to the platform. As an Android developer, it means you’ll have more reach, and you’ll be able to use all of your existing skills, tools, and APIs that make your mobile apps great, to build for a single wearables platform used by people all over the world.

Whether it’s new Jetpack APIs for Wear tailored for small screens and designed to optimize battery life, to the Jetpack Tiles API, so you can create a custom Tile for all the devices in the Wear ecosystem, there are a number of new features to help you build on Wear. And with a new set of APIs for Health and Fitness, created in collaboration with Samsung, data collection from sensors and metrics computation is streamlined, consistent, and accurate–like heart rate to calories to daily distance–from one trusted source. All this comes together in new tooling, with the release of Android Studio Arctic Fox Beta, like easier pairing to test apps, and even a virtual heart rate sensor in the emulator. And when your app is ready, users will have a much easier time discovering the world of Wear apps on Google Play, with some big updates to discoverability. You can read more about all of the Wear updates here.

Tapping the momentum of larger screens, like tablets, Chrome OS and foldables

When it comes to larger screens -- tablets, foldables, and Chrome OS laptops-- there is huge momentum. People are increasingly relying on large screen devices to stay connected with family and friends, go to school, or work remotely. In fact, there are over 250 million active large screen Android devices. Last year, Chrome OS grew +92% year over year–5 times the rate of the PC market, making Chrome OS the fastest growing and the second-most popular desktop OS. To help you take advantage of this momentum, we’re giving you APIs and tools to make optimizing that experience easier: like having your content resize automatically to more space by using SlidingpaneLayout 1.2.0 and a new vertical navigation rail component, Max widths on components to avoid stretched UIs, as well as updates to the platform, Chrome OS, and Jetpack windowmanager, so apps work better by default. You can learn more here.

Google Duo's optimized experience for foldable devices

Google Duo's optimized experience for foldable devices

This is just a taste of some of the new ways we’re making it easier for you to build high quality Android apps. Later today, we’ll be releasing more than 20 technical sessions on Android and Play, covering a wide range of topics such as background tasks, privacy, and Machine Learning on Android, or the top 12 tips to get you ready for Android 12. If building for cars, TVs, and wearables is your thing, we got that covered, too. You can find all these sessions - and more - on the I/O website. Beyond the sessions and news, there’s a number of fun ways to virtually connect with Googlers and other developers at this year’s Google I/O. You can check out the Android dome in I/O Adventure, where you can see new blog posts, videos, codelabs, and more. Maybe even test out your Jetpack Compose skills or take a virtual tour of the cars inside our dome!

#AndroidDevChallenge – It’s a wrap!

Posted by The Jetpack Compose Team

From delightful doggos to creative countdowns and storming weather apps, the 2000 submissions to the #AndroidDevChallenge blew our socks off. We are truly amazed at the creativity and beauty of the apps you built with Jetpack Compose, Android’s new UI toolkit. Now that we judged the final challenge, let’s wrap up, look back at this incredible journey and find out who the winners are!

Week #1 - Puppy adoption app 🐶

The week that made us say “Aww” every time we check out our social media timelines. With this challenge you took your first steps with Compose and learned how to work with lists.

We already shipped the prizes to the first 500 successful submissions: a limited edition trophy of our Jetpack Compose superhero, made of LEGO bricks.

Jetpack Compose prize

Week #1 prize: Jetpack Compose superhero

Week #2 - Countdown timer ⏲️

When time came to implement a countdown timer, you didn’t disappoint! This challenge showed us that you mastered state and animation in Compose.

The first successful 500 submissions already got this week’s prize: a Compose poster pack.

Jetpack Compose prize

Week #2 prize: a Jetpack Compose poster pack

Week #3 - Speed round 🏎

We couldn’t believe how fast you were! This week you had to implement a design provided by us (the designs are still available if you want to try your hand at them in your own time). We opened the challenge in 3 different time zones, each with its own design to build. Here are the winning projects and the time it took to implement each of them:

  • WeTrade Jorge Baños - 2h 43min
  • MySoothe Nezih Yılmaz - 2h 44min
  • Bloom Takaki Hoshikawa - 5h 57min

It was incredible seeing how quickly the winners worked with themes and layouts in Compose; scoring themselves a Pixel 5 each!

Week #4 - Weather app 🌤

Come rain or shine, Android developers don’t disappoint! This week it rained… Compose weather apps. We judged them on 4 categories: code quality, novelty of idea, visual beauty and overall execution. As you made our job quite hard, we got some help from some of our Google Developer Experts to decide the winning projects:

Code quality: Paulo Pereira - JetWeatherfy

Novelty of idea: Roman Levinzon - Colony X Weather

Visual beauty: Chris Horner - Weather Scene

Overall execution: Corentin Bect - Flux

The winners each got a Google Pixel 5!


It was incredible to see what thousands of you built in this Jetpack Compose #AndroidDevChallenge. We hope that the challenge gave you a fun way to start learning Jetpack Compose and get ready to adopt it in your apps. If you’re new to Compose or want to dig deeper, check out our docs, codelabs & samples:

Have fun composing!

Announcing Jetpack Compose Beta!

Posted by Anna-Chiara Bellini, Product Manager, Nick Butcher, Developer Relations

The Android Show: Jetpack Compose, Feb. 24 at 9am PT

Today, we’re launching the beta release of Jetpack Compose, our new UI toolkit designed to make it faster and easier to build native apps across all Android platforms. Compose offers modern, declarative Kotlin APIs, helping you build beautiful, responsive apps with way less code. Built to integrate with existing Android apps and Jetpack libraries, you can adopt Compose at your own pace by combining Android Views and Compose.

With this beta release, Compose is API complete and has all the features you need to build production-ready apps. Beta also means API stable, so we won’t change or remove APIs. Now is a great time to start learning Compose and begin planning for how you will use it in an upcoming project or feature once it reaches 1.0 later this year.

What's In Beta

Our team has been developing Compose in the open with feedback and participation from the community. Since open sourcing development in 2019, we’ve had 30 public releases, addressed over 700 external bugs, and accepted over 200 external contributions. We love seeing what you’ve been building with Compose and have used your feedback and feature requests to refine our APIs and prioritize our work. Since the alpha release, we’ve added and improved a number of new features:

  • 🆕 Coroutines support
  • 🆕 Accessibility support for Talkback - support for other technologies will be in Stable
  • 🆕 Easy to use Animations, with a completely new API since alpha.
  • Interoperability with Views
  • Material UI Components, all with @Sampled code
  • Lazy Lists - Jetpack Compose's take on RecyclerView
  • DSL-based Constraint Layout
  • Modifiers
  • Testing
  • Theming and Graphics, with easy support for Dark and Light mode
  • Input and gestures
  • Text and editable text
  • Window management

For the beta release, we’ve been focused on ensuring API completeness; that all foundational APIs are in place for us to continue to build upon for 1.0 and beyond. We’ll work on stabilizing these APIs up to our 1.0 release with particular focus on app performance and accessibility.

Compose Beta is supported by the latest Canary of Android Studio Arctic Fox, which features many new tools:

    🆕 Live Literals: real time update of literals in Preview and on device or emulator

    🆕 Animation Preview: inspect and playback animations

    🆕 Compose support in the Layout Inspector

    🆕 Interactive preview: inspect and interact with a Composable in isolation

    🆕 Deploy Preview: to deploy a Composable on your device without needing a full app

Live Literals on Android Emulator


Layout Inspector for Jetpack Compose

Works with your existing app

Jetpack Compose is designed to work seamlessly with Android Views, letting you adopt at your own pace. You can embed Compose UIs within Android Views and use Views within Compose. We lay out a number of adoption strategies in our interoperability documentation.

In addition to View interop, we integrate with common libraries to help you to add Compose to your existing applications—no need to rewrite or re-architect your app. We offer integrations with:

  • Navigation
  • ViewModel
  • LiveData / Rx / Flow
  • Paging
  • Hilt

The MDC-Android Compose Theme Adapter and Accompanist libraries provide integrations with Material and AppCompat XML themes so you don’t need to duplicate theme definitions. Accompanist also offers wrappers for common image loading libraries.

Thinking in Compose

Jetpack Compose is a declarative UI toolkit, a paradigm shift from the current View system, where you describe what your UI should look like for a given application state, not how to produce it. Compose takes care of updating your UI when your app state changes, so you don’t have to manipulate your UI into the desired state which can be tedious and error prone.

Built entirely in Kotlin, Compose takes advantage of its great language features to offer powerful, succinct, intuitive APIs. Coroutines for example enable us to write much simpler async APIs such as describing gestures, animation or scrolling. This makes it easier to write code that combines async events, like a gesture which hands off to an animation, all with cancellation and clean-up provided by structured concurrency.

Learning Compose

To help you and your team learn all about Jetpack Compose, we’ve updated our learning pathway; a curated list of videos, hands-on codelabs and key docs to get you started. Today we’re releasing new & updated documentation guides, a number of screencasts and a new Animation Codelab to help dive deeper into how to build with Compose. From guidance on architecture, accessibility and testing, to deep dives into animation, lists or thinking in Compose, we have guides to help you get up to speed.

We also offer 8 official sample applications if you want to jump straight in and see Compose in action. We have simple to complex samples, each showcasing different APIs and use cases. Check the readme for more details.


#AndroidDevChallenge: learn Compose and win prizes

If you’re ready to get started with Compose–and also want to win some prizes along the way, check out the #AndroidDevChallenge. For the next four weeks, we’ll have weekly challenges designed to give your very own insights into Jetpack Compose, so you can fly through your projects. Compete to win new prizes for each challenge, with over one thousand prizes to win including a Google Pixel 5. You can read more about the first weekly challenge - starting today - right here.

With Jetpack Compose reaching Beta—with stable APIs and feature complete for 1.0—it's a great time to start learning Jetpack Compose and planning how you might use it in an upcoming project. We’d love to hear your feedback on adopting Compose in your app or join the discussion in the Kotlin Slack #compose channel.

Announcing Jetpack Compose Alpha!

Posted by Karen Ng, Director, Product Management

Today, we’re releasing the alpha of Jetpack Compose, our modern UI toolkit designed to help you quickly and easily build beautiful apps across all Android platforms, with native access to the platform APIs. Bring your app to life with dramatically less code, interactive tools, and intuitive Kotlin APIs.

No matter where you’re working from -- whether it’s your kitchen table or an office, we know you need a programming language, an IDE and a powerful UI framework that can save you time and reduce how much code you need to write. So we built Jetpack Compose to make you (and us!) more productive with building UI.

We started with Android Jetpack — taking the hardest, most common developer problems on Android and creating a suite of libraries that ensure high quality apps that work across all versions of the platform. Today, 84% of the top 10,000 apps in the Play store are using a Jetpack library.

Then we heard how developers love Kotlin, with over 70% of the top 1000 apps and 60% of pro Android developers using Kotlin today. The Google Home app saw, in certain instances, an 80% reduction in lines of code by using Kotlin and a decrease of NullPointerExceptions by 33% compared to a similar past period. Duolingo, saw reduced line count by an average of 30%.

Finally, we heard strong feedback from the community that developers like the simplicity of declarative APIs for building UI. Jetpack Compose combines all three of these: APIs for high quality apps at scale, an intuitive language, and a reactive programming model.

Jetpack

Jetpack Compose: Now in Alpha

Jetpack Compose Alpha has what you need to build full-fledged Android apps, including powerful tools and interoperability with existing Android views so you don’t need to rewrite your app. Compose APIs are designed and developed hand-in-hand with a set of canonical sample apps that use Material Design that we’re excited to release today! You can import and explore the latest samples directly in Android Studio as well.

compose

The alpha release includes:

  • Animations
  • Constraint Layout
  • Initial A11Y support
  • Input and Gestures
  • Interoperability with Views (start mixing Composable functions in your existing app)
  • Lazy Lists
  • Material UI components
  • Performance optimizations
  • Testing
  • Text and editable Text
  • Theming and Graphics
  • Window management

We've also added a number of new capabilities to Android Studio 4.2 canary, in close partnership with the JetBrains Kotlin team, to help you build apps with Compose:

  • Compose Code completion
  • Compose Preview Annotations
  • Deploy individual composables to any device
  • Interactive Compose previews
  • Kotlin compiler plugin for code generation
  • Sample Data API for Compose

Thinking in Compose

Compose uses a programming model that is quite different from the existing model of building UI on Android. Historically, an Android view hierarchy has been represented as a tree of UI widgets. As the state of the app changes, the UI hierarchy needs to be updated to display the current data. The most common way of updating the UI is to walk the tree using functions like findViewById(), and change nodes by calling methods like:

 button.setText(String) 
container.addView(View) 
 img.setImageBitmap(Bitmap) 
These methods change the internal state of the widget. Not only can this be tedious, but updating views manually increases the likelihood of errors (e.g. forgetting to update a view).

Jetpack Compose is a fully declarative component-based approach, meaning you describe your UI as functions that transform data into a UI hierarchy. When the underlying data changes, the Compose framework automatically updates the UI hierarchy for you, making it simple to build UIs easily and quickly.

Full interop with existing Android views

Adopting any new framework is a big change for existing projects and codebases, which is why we’ve designed Compose to be as easy to adopt as Kotlin — it is fully interoperable with existing Android code, from day one.

Migrating to Compose depends on you and your team. If you're building a new app, the best option might be to implement your entire UI with Compose. We know that most of you have large existing codebases, so rather than rewriting your app, you can combine Compose with your existing UI design.

There are two main ways you can combine Compose with a view-based UI:

  • You can add Compose elements into your existing UI, either by creating an entirely new Compose-based screen, or by adding Compose elements into an existing fragment or view layout.
  • You can add a view-based UI element into your composable functions. Doing so lets you add non-Compose widgets, such as MapView or WebView, into a Compose-based design.

We’ve also published a new library, MDC Compose Theme Adapter, which allows you to reuse your existing Material Components themes within your Compose UI.

To learn more, try the Compose for existing apps codelab or check out these two samples:

  • Tivi and Sunflower are existing apps which are being integrated with Compose
  • Crane sample app, embeds a MapView in Compose

Powerful Tools

Jetpack Compose is built with powerful tooling in Android Studio, designed to help you iterate quickly on the piece of UI you’re working on.

The Compose layout preview enables you to preview your Compose components without having to deploy your app to a device or emulator. As you develop your app, your previews update to help you review your changes faster. To create a layout preview, write a composable function that does not take any parameters, and add the

 @Preview annotation 
After you build your app, the preview function's UI appears in Studio's Preview pane.

Jetpack

Android Studio provides an interactive preview mode. While you're in interactive preview mode, you can click or type in your UI elements, and the UI responds as if it were in the installed app.

Jetpack

You can also deploy a single composable to your physical device or Android Emulator. Android Studio creates a new activity containing the UI generated by that function, and deploys it to your app on the device. This lets you try out the UI on an actual device without needing to reinstall the entire app or navigate to its location.

Jetpack

Get started with Jetpack Compose

To get started with Jetpack Compose, try the Compose Tutorial and get setup. Or dive right into the sample apps and walk through those apps in ‘Compose by Example’:

To find a comprehensive set of Compose resources, from new codelabs and expanded documentation, see the Compose pathway.

Since we open-sourced Jetpack Compose last year, so many of you have given us invaluable feedback, logged bugs, or contributed CLs and have gotten us where we are today. Thank you!

Compose isn’t recommended for full production use yet, in particular as we work towards API stability and finish performance optimizations, but we’d love you to give it a try and share feedback. Join us in the discussion on the #compose channel at Kotlin Slack. Compose 1.0 is expected in 2021.

Happy Composing!

What’s New with Android Jetpack

Posted by Karen Ng, Group Product Manager and Jisha Abubaker, Product Manager, Android

Last year, we launched Android Jetpack, a collection of software components designed to accelerate Android development and make writing high-quality apps easier. Jetpack was built with you in mind -- to take the hardest, most common developer problems on Android and make your lives easier.

Jetpack has seen incredible adoption and momentum. Today, 80% of the top 1,000 apps in the Play store are using Jetpack. We’ve also heard feedback from so many of you across our early access developer programs and user studies, as well as Reddit, Stack Overflow, and Slack, that has helped shape these APIs. Very humbly, thank you.

What’s New in Jetpack

Today, we are excited to share with you 11 Jetpack libraries that can be used in development now and an early-development, open-source project called Jetpack Compose to simplify UI development.

Now in Alpha

CameraX

We've heard from many of you that developing camera apps or integrating camera functionality within your existing apps is hard. With the new CameraX library, we want to enable you to create great camera-driven experiences in your application without worrying about the underlying device behavior. This API is backwards compatible to Android 5.0 (API 21) or higher, ensuring that the same code works on most devices in the market. While it leverages the capabilities of camera2, it uses a simpler, use case-based approach that is lifecycle-aware eliminating significant amount of boilerplate code vs camera2. Finally, it enables you to access the same functionality as the native camera app on supported devices. These optional Extensions enable features like Portrait, Night, HDR, and Beauty.

LiveData and Lifecycles w/ coroutines

We heard you loud and clear and agree that LiveData must support your common one-shot asynchronous operations. With Lifecycle & LiveData KTX, you can do so with Kotlin coroutines that are lifecycle-aware. Kotlin coroutines have been well received by the developer community for how they simplify the way concurrency is handled within Android apps. We want to simplify it even further and enabling you to use them safely by offering coroutine scopes tied to lifecycles, coroutine dispatchers that are lifecycle-aware, and support for simple asynchronous chains with the new liveData builder.

Benchmark

The Benchmark library provides you a quick way to benchmark your app code, whether it is written in Kotlin, the Java programming language or native code. We use this library to continuously benchmark Jetpack libraries we release to ensure we do not introduce any latency into your code. You can now do the same right within your development environment in Android Studio, easily measuring database queries, view inflation, or a RecyclerView scroll. The library takes care of what is needed to provide reliable and consistent results like handling warm-up periods, removing outliers, and locking CPU clocks.

Security

To maximize security of an application’s data at-rest, the new Security library implements security best practices for you. It provides strong security that balances encryption with performance for consumer apps like banking and chat. It also provides a maximum level of security for apps that require a hardware-backed keystore with user presence and simplifies many operations including key generation and validation.

ViewModel with SavedState

ViewModel provided you an easy way to save your UI data in the event of a configuration change. It did not save your app state in the event of process death, and many of you have been relying on SavedInstanceState alongside ViewModel. With the ViewModel with SavedState module, you can eliminate boilerplate code and gain the benefits of using both ViewModel and SavedState with simple APIs to save and retrieve data right from your ViewModel.

ViewPager2

ViewPager2, the next generation of ViewPager, is now based on RecyclerView and supports vertical scrolling and RTL (Right-to-Left) layouts. It also provides a much easier way to listen for page data changes with registerOnPageChangeCallback.

Now in Beta

ConstraintLayout 2.0

ConstraintLayout 2.0 brings up new optimizations, and new way of customizing layouts, with the addition of helper classes. As part of ConstraintLayout 2.0, MotionLayout provides an easy way to manage motion and widget animation in your applications. You can easily describe transitions between layouts and animation of properties. MotionLayout is fully declarative in XML, allowing you to describe even complex transitions without requiring any code.

Biometrics Prompt

Users are accustomed to biometric credentials on their phones, but if your app requires a biometric login, it is important to make sure that users are provided a consistent and safe way to enter their credentials. The Biometrics library provides a simple system prompt giving the user a trustworthy experience.

Enterprise

With the Jetpack Enterprise library, your managed enterprise apps can send feedback back to Enterprise Mobility Management providers in the form of keyed app states, while taking advantage of backwards compatibility with managed configurations.

Android for Cars

With the Android for Cars libraries, you can provide your users a driver-optimized version of your app that will be automatically installed onto the vehicle’s infotainment system in vehicles equipped with the Android Automotive OS. It also allows your apps to work with the Android Auto app, providing the driver-optimized version anytime on their device.

Now in Stable

And in case you missed it, we announced stable releases of Jetpack WorkManager (background processing) and Jetpack Navigation (in-app navigation) just a few months ago.

Jetpack Compose

Today, we open-sourced an early preview of Jetpack Compose, a new unbundled toolkit designed to simplify UI development by combining a reactive programming model with the conciseness and ease-of-use of Kotlin. We have always done our best work when we did it with you - our developer community. That’s why we decided to develop Jetpack Compose in the open, starting today.

In that vein, we took a step back and chatted with many of you. We heard strong feedback from developers that they like the modern, reactive APIs that Flutter, React Native, Litho, and Vue.js represent. We also heard that developers love Kotlin, with over 53% of professional Android developers using it and with 20% higher language satisfaction ratings than the Java programming language. Kotlin has become the fastest-growing language in terms of number of contributors on GitHub.

So, we decided to invest in the reactive approach to declarative programming and create an easier way to build UIs with Kotlin.

We are building Compose with a few core principles:

  • Build with the benefits that Kotlin brings -- concise, safe, and fully interoperable with the Java programming language. Designed to drastically reduce the amount of boilerplate code you have to write, so you can focus on your app code, and help avoid entire classes of errors.
  • Fully declarative for defining UI components, including drawing and creating custom layouts. Simply describe your UI as a set of composable functions, and the framework handles UI optimizations and updates to the view hierarchy under the hood.
  • Provide reusable building blocks that let you build custom widgets easier, and without starting from scratch.
  • Compatible with existing views so you can mix and match and adopt at your own pace with direct access to all of the Android and Jetpack APIs.
  • Material Design out of the box and animations from the start, so it’s easy to create beautiful apps that are full of motion.
  • Accelerate development with tools like live preview and apply changes.

A Compose application is made up of composable functions that transform application data into a UI hierarchy. A function is all you need to create a new UI component. To create a composable function just add the @Composable annotation to the function name. Under the hood, Compose uses a custom Kotlin compiler plug-in so when the underlying data changes, the composable functions can be re-invoked to generate an updated UI hierarchy. The simple example below prints a string to the screen.

We know that adopting any new framework is a big change for existing projects and codebases, which is why we’ve designed Compose like all of Jetpack -- with individual components that you can adopt at your own pace and are compatible with existing views.

If you want to learn more about Jetpack Compose or download its source to try it for yourself, check out http://d.android.com/jetpackcompose

We'd love to hear from you as we iterate on this exciting future together. Send us feedback by posting comments below, and please file any bugs you run into on AOSP or directly through the feedback buttons in the Android Studio Jetpack Compose build in AOSP. Since this is an early preview, we do not recommend trying this on any production projects.

Happy Jetpacking!