Tag Archives: Android Jetpack

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!

Google I/O 2019: Empowering developers to build the best experiences on Android + Play

Posted by Chet Haase

It's great to be in our backyard again for Google I/O to connect with Android’s developers around the world. The 7,200 attendees at Shoreline Amphitheatre, millions of viewers on the livestream, and thousand of developers at local I/O Extended events across 80+ countries heard about our efforts to make the lives of developers easier. Today at Google I/O, we talked about two big themes; helping our developers become more productive and strengthening user privacy and security in the platform. Let's take a closer look at the major developer news at I/O so far:

Developer Productivity

This year, we focused on a simple idea - we want to save you time every today. By making everything you use even better.

Kotlin

Two years ago, we announced Kotlin was a supported language for Android. Our top developers loved it already, and since then, it’s amazing how fast it’s grown. Over 50% of professional Android developers now use Kotlin, it’s been one of the most-loved languages two years running on Stack Overflow, and one of the fastest-growing on GitHub in number of contributors.

Today we’re announcing another big step: Android development will become increasingly Kotlin-first. Many new Jetpack APIs and features will be offered first in Kotlin. If you’re starting a new project, you should write it in Kotlin; code written in Kotlin often mean much less code for you–less code to type, test, and maintain. And, in partnership with Jetbrains and the Kotlin Foundation, we’re continuing to invest in tooling, docs, trainings and events to make Kotlin even easier to learn and use. This includes Kotlin/Everywhere, a new, global series of events where you can learn more about the language, new Udacity courses, and more.

Android Jetpack

Last year, we announced Android Jetpack, Android’s API to accelerate Android development and make writing high-quality apps easy, with less code. Over 80% of our top 1000 apps are already using Jetpack, as we continue to simplify more every-day developer challenges. Today, we are releasing 6 new Jetpack libraries (in alpha), and bringing 5 libraries to beta quality. Here are 3 highlights:

  • CameraX - You’ve told us working effectively across the range of unique Android devices was tough. CameraX is a new open-source Android Jetpack library to make camera development easier and faster. It provides a consistent camera experience across devices, so you no longer have to maintain device specific configurations. You’ll find support for leading-edge hardware and software features like optical zoom, bokeh, HDR, and night mode on participating manufacturer devices. It works with almost 90% of devices (backwards compatible to L). There’s also an easy migration path from legacy Camera APIs and it works seamlessly with camera2 APIs. 70% of camera usage on Android comes from installed apps (not the device camera app) so we’re really excited to make camera development easier.

  • Architecture Components - We’ve made a number of additions and enhancements based on your feedback. You’ve told us concurrency on Android was hard. So we’re bringing you LiveData and Lifecycles w/ coroutines to support common one-shot asynchronous operations. 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. And in case you missed it, we announced stable releases of WorkManager (background processing) and Navigation (navigation between app screens) just a couple of months ago.
  • Jetpack Compose - Many of you have been asking us for a modern, reactive style UI toolkit for Android, which takes advantage of Kotlin and integrates seamlessly with the platform and all of your existing code. Today, we’re sharing the team’s work on Jetpack Compose. Jetpack Compose is designed to simplify UI development by combining a reactive programming model with the conciseness and ease-of-use of Kotlin. It’s compatible with the existing UI toolkit, so you can mix and match views with direct access to all of the Android and Jetpack APIs. It’s also fully declarative for defining UI components. And, it’s designed with Material, animations, and tools in mind from the start. Starting today we’re developing this in the open, and you can find all the code on AOSP.

Android Studio

Today we’re releasing Android Studio 3.5 to Beta. For months, the team has been exclusively focused on refining and polishing day-to-day development workflows, with Project Marble. Android Studio 3.5 includes better IDE memory management for large projects, lower typing latency, lint improvements, CPU usage optimizations, layout editor improvements, emulator improvements, build changes, as well as a complete rewrite of Instant Run, now called Apply Changes, that now reliably accelerates the ability to see your code changes on a device - plus over 400 high- priority bug fixes.

Machine Learning at Android scale

In Android Q, we’ve made significant improvements to Android’s Neural Networks API (NNAPI). First, we have increased the number of Operators supported from 38 to over 90. The vast majority of models can now be accelerated by NNAPI with no alterations. We’ve also introduced an introspection API for advanced users, allowing full control over which hardware components handle acceleration (e.g. DSP vs. NPU). And, we’ve worked closely with hardware vendors to deliver significant improvements in performance, both in latency and power consumption. Working with MediaTek, we were able to accelerate ML Kit’s face detection API by 9X on the Helio P90. Working with Qualcomm, we were able to accelerate Google’s Lens OCR on the Snapdragon 855’s AI Engine, increasing speed by 3X while also reducing power consumption by 3.7X.

Dynamic features and in-app updates

Last year we introduced the Android App Bundle to help you reduce app size and increase installs. Since then, we’ve seen over 80,000 app bundles in production, with average size savings of 20%. And today we have a number of announcements to help you reduce size and deliver updates to your users even faster. Today we’re glad to share that dynamic feature modules are moving from beta to stable. With dynamic feature modules, you can reduce your app size even more by choosing which parts of your app to deliver - based on conditions like device features, country. You can even deliver modules on-demand, instead of at install time. And today we’re also moving in-app updates from beta to stable. The ability to dynamically update apps is something you’ve been requesting for a long time. Let’s say you have a crucial bug in your app, and you need to push it out right away; you don’t want to wait until users discover an update in the Play Store. Now you can.

User privacy and security in Android Q

As a developer community, we all care about getting this right. It’s about building a platform that offers powerful capabilities for developers, while making sure that user safety and privacy is protected. We introduced Android Q Beta a few months ago with over 50 features and improvements around user privacy and security. These Q changes provide users more transparency and control.

As always, we are working hard to do everything we can for developers adopting the new release. We know you have your own features to build. That’s why, with these Q changes, we’ve worked very hard to minimize the impact for you, as well as to incorporate your feedback. We’ve given as long a notice period as possible, as well as complete and detailed technical information up front, to make it as easy as possible to adopt. We also want to thank the community for your ongoing feedback. It’s been a huge help to the team who are working hard to get this right. A great example are the Beta 3 storage changes, where your feedback helped us evolve the feature over the course of the Betas. Android has a longstanding commitment to minimizing all breaking changes. Our commitment is unchanged, and we’ll work hard to keep Android the open, flexible, and developer friendly platform we all love.

Be a part of Google I/O!

We’ve got a lot of great content in store for you over the next three days, including over 45 sessions across Android. We’re excited for you to join us in-person here at Shoreline, at an I/O Extended event, or online through the livestream. We’re constantly investing in our platform that connects developers to billions of users around the world. To the entire Android community, thank you for your continued support and feedback, and for being a part of Android.

Android Jetpack Navigation Stable Release

Posted by Ian Lake, Software Engineering Lead & Jisha Abubaker, Product Manager

Cohesive tooling and guidance for implementing predictable in-app navigation

Today we're happy to announce the stable release of the Android Jetpack Navigation component.

The Jetpack Navigation component's suite of libraries, tooling and guidance provides a robust, complete navigation framework, freeing you from the challenges of implementing navigation yourself and giving you certainty that all edge cases are handled correctly.

With the Jetpack Navigation component you can:

  • Handle basic user actions like Up & Back buttons so that they work consistently across devices and screens.
  • Allow users to land on any part of your app via deep links and build consistent and predictable navigation within your app.
  • Improve type safety of arguments passed from one screen to another, decreasing the chances of runtime crashes as users navigate in your app.
  • Add navigation experiences like navigation drawers and bottom navigation consistent with the Material Design guidelines.
  • Visualize and manipulate your navigation flows easily with the Navigation Editor in Android Studio 3.3

The Jetpack Navigation component adheres to the Principles of Navigation, providing consistent and predictable navigation no matter how simple or complex your app may be.

Simplify navigation code with Jetpack Navigation Libraries

The Jetpack Navigation component provides a framework for in-app navigation that makes it possible to abstract away the implementation details, keeping your app code free of navigation boilerplate.

To get started with the Jetpack Navigation component in your project, add the Navigation artifacts available on Google's Maven repository in Java or Kotlin to your app's build.gradle file:

 dependencies {
    def nav_version = 2.0.0

    // Java
    implementation "androidx.navigation:navigation-fragment:$nav_version"
    implementation "androidx.navigation:navigation-ui:$nav_version"

    // Kotlin KTX 
    implementation "androidx.navigation:navigation-fragment-ktx:$nav_version"
    implementation "androidx.navigation:navigation-ui-ktx:$nav_version"
  }

Note: If you have not yet migrated to androidx.*, the Jetpack Navigation stable component libraries are also available as android.arch.* artifacts in version 1.0.0.

navigation-runtime : This core library powers the navigation graph, which provides the structure of your in-app navigation: the screens or destinations that make up your app and the actions that link them. You can control how you navigate to destinations with a simple navigate() call. These destinations may be fragments, activities or custom destinations.

navigation-fragment: This library builds upon navigation-runtime and provides out-of-the-box support for fragments as destinations. With this library, fragment transactions are now handled for you automatically.

navigation-ui: This library allows you to easily add navigation drawers, menus and bottom navigation to your app consistent with the Material Design guidelines.

Each of these libraries provide an Android KTX artifact with the -ktx suffix that builds upon the Java API, taking advantage of Kotlin-specific language features.

Tools to help you build predictable navigation workflows

Available in Android Studio 3.3 and above, the Navigation Editor lets you visually create your navigation graph , allowing you to manage user journeys within your app.

With integration into the manifest merger tool, Android Studio can automatically generate the intent filters necessary to enable deep linking to a specific screen in your app. With this feature, you can associate URLs with any screen of your app by simply setting an attribute on the navigation destination.

Navigation often requires passing data from one screen to another. For example, your list screen may pass an item ID to a details screen. Many of the runtime exceptions during navigation have been attributed to a lack of type safety guarantees as you pass arguments. These exceptions are hard to replicate and debug. Learn how you can provide compile time type safety with the Safe Args Gradle Plugin.

Guidance to get it right on the first try

Check out our brand new set of developer guides that encompass best practices to help you implement navigation correctly:

What developers say

Here's what Emery Coxe, Android Lead @ HomeAway, has to say about the Jetpack Navigation component :

"The Navigation library is well-designed and fully configurable, allowing us to integrate the library according to our specific needs.

With the Navigation Library, we refactored our legacy navigation drawer to support a dynamic, runtime-based configuration using custom views. It allowed us to add / remove new screens to the top-level experience of our app without creating any interdependencies between discreetly packaged modules.

We were also able to get rid of all anti-patterns in our app around top-level navigation, removing explicit casts and hardcoded assumptions to instead rely directly on Navigation. This library is a fundamental component of modern Android development, and we intend to adopt it more broadly across our app moving forward.

Get started

Check out the migration guide and the developer guide to learn how you can get started using the Jetpack Navigation component in your app. We also offer a hands-on codelab and a sample app.

Also check out Google's Digital Wellbeing to see another real-world example of in-app navigation using the Android Jetpack Navigation component.

Feedback

Please continue to tell us about your experience with the Navigation component. If you have specific feedback on features or if you run into any issues, please file a bug via one of the following links:

Android Jetpack WorkManager Stable Release

Posted by Sumir Kataria, Software Engineering Lead & Jisha Abubaker, Product Manager

Simplify how you manage background work with WorkManager

Today, we're happy to announce the release of Android Jetpack WorkManager 1.0 Stable. We want to thank so many of you in our dev community who have given us feedback and logged bugs along the way - we've gotten here thanks to your help!

When we looked at the top problems faced by developers, we saw that doing background processing reliably and in a battery-friendly manner was a huge challenge. This meant that periodically fetching fresh content or uploading your logs was complex. Different versions of Android provided different tools for the job, each with their own API quirks. For example, listening for network or storage availability and automatically retrying your tasks involved a lot of work.

Our answer to these challenges was WorkManager. We introduced a preview of the Android Jetpack WorkManager library at Google I/O 2018 and have since iterated on it with additional features and bug fixes thanks to your valuable input.

The goal of WorkManager is to make background operations easy for you. WorkManager takes into account constraints like battery-optimization, storage, or network availability, and it only runs its tasks when the appropriate conditions are met. It also knows when to retry or reschedule your work--even if your device or app restarts.

We believe WorkManager is a friendly, approachable API that can take care of one of the most complex parts of Android for you so you can focus on the code that makes your app unique.

WorkManager Highlights

Here are some key features of WorkManager:

  • Lets you set constraints, such as network status or charge state, on when the task runs
  • Supports asynchronous one-off and periodic tasks
  • Supports chained tasks with input & output
  • Ensures task execution, even if the app or device restarts
  • Supports Android 4.0+ (API 14+)

Watch and read below to learn when and how to use WorkManager to simplify managing background work in your apps:

When to use WorkManager

WorkManager is best suited for tasks that can be deferred, but are still expected to run even if the application or device restarts (for example, syncing data periodically with a backend service and uploading logs or analytics data).

For tasks like sending an instant message that are required to run immediately or for tasks that are not required to run after the app exits, take a look at our background processing guide to learn which solution meets your needs.

How to use WorkManager

To get started with the WorkManager API, add the WorkManager dependency available on Google's Maven repository in Java or Kotlin to your application's build.gradle file:

dependencies {
    def work_version = 1.0.0

    // Java
    implementation "android.arch.work:work-runtime:$work_version"

    // Kotlin KTX + coroutines
    implementation "android.arch.work:work-runtime-ktx:$work_version"
  }

Now, simply subclass a Worker and implement your background work with doWork() and enqueue it with WorkManager.

class MyWorker(ctx: Context, params: WorkerParameters)
  : Worker(ctx, params) {
  override fun WorkerResult doWork() {
    //do the work you want done in the background here
    return Result.success()
  }
}

// optionally, add constraints like power, network availability
val constraints: Constraints = Constraints.Builder()
     .setRequiresCharging(true)
                .setRequiredNetworkType(NetworkType.CONNECTED)
                .build()

val myWork = OneTimeWorkRequestBuilder<MyWorker>()
                .setConstraints(constraints).build()

// Now, enqueue your work
WorkManager.getInstance().enqueue(myWork)

WorkManager will now take care of running your task when it detects that your device is charging and the network is available.

Why use WorkManager

Backward compatibility

WorkManager will leverage the right scheduling API under the hood: it uses JobScheduler API on Android 6.0+ (API 23+) and a combination of AlarmManager and BroadcastReceiver on previous versions.

It also seeks to ensure the best possible behavior so that it complies with system optimizations introduced in newer Android API versions to maximize battery and enforce good app behavior.

For example, WorkManager will schedule background work during the maintenance window for Android 6.0+ (API 23+) devices when the system is in Doze mode.

Reliable scheduling

With WorkManager, you can easily add constraints like network availability or charging status. Your work will run when the constraints are met and automatically retried if they fail while running. For example, if your task requires network to be available, the task will be stopped when network is no longer available and retried later.

You can also monitor work status and retrieve work result using LiveData. This allows your UI to be notified when your task is completed.

In the event that your work fails, you can control how your work is retried by configuring how backoff is handled.

WorkManager is also able to reschedule your work, using a record of your work in its local database, if an application or device restart occurs.

Control over how your work is run

We understand that each app has unique needs, and so do your tasks--even within the same app. WorkManager provides a simple yet highly flexible API surface to help configure your work and how it is run.

Take advantage of one-off scheduling with OneTimeWorkRequest or recurrent scheduling with PeriodicWorkRequest.

You can also chain your one time work requests to run in order or in parallel. If any work in the chain fails, WorkManager seeks to ensure that the remaining chain of work will not run. Read more about chaining work requests here.

If you require more flexibility over how WorkManager parallelizes and manages work, check out our advanced threading guide.

What developers have to say

redBus, the largest online bus ticketing platform, shares their experience using WorkManager to simplify how they collect user feedback in their Android app:

"Feedback is critical to redBus as we expand into other countries. It often happens that a user gives critical feedback about a functionality within the redBus app but when the app tries to upload the feedback to backend servers, there might not be enough network coverage or battery.
WorkManager has simplified the way redBus app delivers information to it's backend servers. WorkManager library's capability to handle parameters like network connectivity, battery and use appropriate handlers like AlarmManager or JobScheduler has enabled us to concentrate on building business logics and offloading execution complexity to WorkManager."

- Dinesh Shanmugam

Android Lead, redBus.in

Get started with WorkManager

Check out our getting started guide and hands-on codelab to start using the WorkManager library for your background task needs.

We appreciate your feedback, including features you like and features you would like to see.

If you find a bug or issue, feel free to file an issue.