Snapchat's Android app is pretty universally hated for poor performance and the occasional lack of features next to its iOS counterpart, and it's been that way since it first launched. Snapchat has teased nebulous "improvements" for a while now, but so far we haven't actually see anything worth mentioning, besides UI updates that also go […]

Come comment on this article: New Snapchat update for Android teases better performance and new features

19 Aug 2018 2:23pm GMT

Posted by Benjamin Baxter, Developer Advocate and Bacon Connoisseur

All TVs have the same problem with keyboard input: It is very cumbersome to hunt and peck for each letter using a D-pad with a remote. And if you make a mistake, trying to correct it compounds the problem.

APIs like Smart Lock and Autofill, can ease user's frustrations, but for certain types of input, like login, you need to collect complex input that is difficult for users using the on-screen keyboard.

With the Nearby Connections API, you can use a second screen to gather input from the user with less friction.

How Nearby Connections works

From the documentation:

"Nearby Connections is an offline peer-to-peer socket model for communication based on advertising and discovering devices in proximity.

Usage of the API falls into two phases: pre-connection, and post-connection.

In the pre-connection phase, Advertisers advertise themselves, while Discoverers discover nearby Advertisers and send connection requests. A connection request from a Discoverer to an Advertiser initiates a symmetric authentication flow that results in both sides independently accepting (or rejecting) the connection request.

After a connection request is accepted by both sides, the connection is established and the devices enter the post-connection phase, during which both sides can exchange data."

In most cases the TV is the advertiser and the phone is the discoverer. In the example below, the assumed second device is a phone. The API and patterns described in this article are not limited to a phone. For example, a tablet could also be the second screen device.

Login Example

There are many times when keyboard input is required. Authenticating users and collecting billing information (like zip codes and name on card) are common cases. This example handles a login flow that uses a second screen to see how Nearby Connections can help reduce friction.

1. The user opens your app on her TV and needs to login. You can show a screen of options similar to the setup flow for a new TV.

2. After the user chooses to login with their phone, the TV should start advertising and send the user to the associated login app on their phone, which should start discovering.

There are a variety of solutions to open the app on the phone. As an example, Android TV's setup flow has the user open the corresponding app on their mobile device. Initiating the hand-off is a more a UX concern than a technology concern.

3. The phone app should display the advertising TV and prompt the user to initiate the connection. After the (encrypted -- see Security Considerations below for more on this) connection is established the TV can stop advertising and the phone can stop discovering.

"Advertising/Discovery using Nearby Connections for hours on end can affect a device's battery. While this is not usually an issue for a plugged-in TV, it can be for mobile devices, so be conscious about stopping advertising and discovery once they're no longer needed."

4. Next, the phone can start collecting the user's input. Once the user enters their login information, the phone should send it to the TV in a BYTES payload over the secure connection.

5. When the TV receives the message it should send an ACK (using a BYTES payload) back to the phone to confirm delivery.

6. When the phone receives the ACK, it can safely close the connection.

The following diagram summarizes the sequence of events:

UX considerations

Nearby Connections needs location permissions to be able to discover nearby devices. Be transparent with your users. Tell them why they need to grant the location permission on their phone.

Since the TV is advertising, it does not need location permissions.

Start advertising: The TV code

After the user chooses to login on the phone, the TV should start advertising. This is a very simple process with the Nearby API.

override fun onGuidedActionClicked(action: GuidedAction?) {
    super.onGuidedActionClicked(action)
    if( action == loginAction ) {
        // Update the UI so the user knows to check their phone
        navigationFlowCallback.navigateToConnectionDialog()
        doStartAdvertising(requireContext()) { payload ->
            handlePayload(payload)
        }
    }
}

When the user clicks a button, update the UI to tell them to look at their phone to continue. Be sure to offer a way to cancel the remote login and try manually with the cumbersome onscreen keyboard.

This example uses a GuidedStepFragment but the same UX pattern applies to whatever design you choose.

Advertising is straightforward. You need to supply a name, a service id (typically the package name), and a `ConnectionLifeCycleCallback`.

You also need to choose a strategy that both the TV and the phone use. Since it is possible that the users has multiple TVs (living room, bedroom, etc) the best strategy to use is P2P_CLUSTER.

Then start advertising. The onSuccessListener and onFailureListener tell you whether or not the device was able to start advertising, they do not indicate a device has been discovered.

fun doStartAdvertising(context: Context) {
    Nearby.getConnectionsClient(context).startAdvertising(
        context.getString(R.string.tv_name),
        context.packageName,
        connectionLifecycleCallback,
        AdvertisingOptions.Builder().setStrategy(Strategy.P2P_CLUSTER).build()
    )
    .addOnSuccessListener {
        Log.d(LoginStepFragment.TAG, "We are advertising!")
    }
    .addOnFailureListener {
        Log.d(LoginStepFragment.TAG, "We cannot start advertising.")
        Toast.makeText(
            context, "We cannot start advertising.", Toast.LENGTH_LONG)
                .show()
    }
}

The real magic happens in the `connectionLifecycleCallback` that is triggered when devices start to initiate a connection. The TV should accept the handshake from the phone (after performing the necessary authentication -- see Security Considerations below for more) and supply a payload listener.

val connectionLifecycleCallback = object : ConnectionLifecycleCallback() {

    override fun onConnectionInitiated(
            endpointId: String, 
            connectionInfo: ConnectionInfo
    ) {
        Log.d(TAG, "Connection initialized to endpoint: $endpointId")
        // Make sure to authenticate using `connectionInfo.authenticationToken` 
        // before accepting
        Nearby.getConnectionsClient(context)
            .acceptConnection(endpointId, payloadCallback)
    }

    override fun onConnectionResult(
        endpointId: String, 
        connectionResolution: ConnectionResolution
    ) {
        Log.d(TAG, "Received result from connection: ${connectionResolution.status.statusCode}")
        doStopAdvertising()
        when (connectionResolution.status.statusCode) {
            ConnectionsStatusCodes.STATUS_OK -> {
                Log.d(TAG, "Connected to endpoint: $endpointId")
                otherDeviceEndpointId = endpointId
            }
            else -> {
                otherDeviceEndpointId = null
            }
        }
    }

    override fun onDisconnected(endpointId: String) {
        Log.d(TAG, "Disconnected from endpoint: $endpointId")
        otherDeviceEndpointId = null
    }
}

The payloadCallback listens for the phone to send the login information needed. After receiving the login information, the connection is no longer needed. We go into more detail later in the Ending the Conversation section.

Discovering the big screen: The phone code

Nearby Connections does not require the user's consent. However, the location permission must be granted in order for discovery with Nearby Connections to work its magic. (It uses BLE scanning under the covers.)

After opening the app on the phone, start by prompting the user for location permission if not already granted on devices running Marshmallow and higher.

Once the permission is granted, start discovering, confirm the connection, collect the credentials, and send a message to the TV app.

Discovering is as simple as advertising. You need a service id (typically the package name -- this should be the same on the Discoverer and Advertiser for them to see each other), a name, and a `EndpointDiscoveryCallback`. Similar to the TV code, the flow is triggered by callbacks based on the connection status.

Nearby.getConnectionsClient(context).startDiscovery(
        context.packageName,
        mobileEndpointDiscoveryCallback,
        DiscoveryOptions.Builder().setStrategy(Strategy.P2P_CLUSTER).build()
        )
        .addOnSuccessListener {
            // We're discovering!
            Log.d(TAG, "We are discovering!")
        }
         .addOnFailureListener {
            // We were unable to start discovering.
            Log.d(TAG, "We cannot start discovering!")
        }

The Discoverer's listeners are similar to the Advertiser's success and failure listeners; they signal if the request to start discovery was successful or not.

Once you discover an advertiser, the `EndpointDiscoveryCallback` is triggered. You need to keep track of the other endpoint to know who to send the payload, e.g.: the user's credentials, to later.

val mobileEndpointDiscoveryCallback = object : EndpointDiscoveryCallback() {
    override fun onEndpointFound(
        endpointId: String, 
        discoveredEndpointInfo: DiscoveredEndpointInfo
    ) {
        // An endpoint was found!
        Log.d(TAG, "An endpoint was found, ${discoveredEndpointInfo.endpointName}")
        Nearby.getConnectionsClient(context)
            .requestConnection(
                context.getString(R.string.phone_name), 
                endpointId, 
                connectionLifecycleCallback)
    }

    override fun onEndpointLost(endpointId: String) {
        // A previously discovered endpoint has gone away.
        Log.d(TAG, "An endpoint was lost, $endpointId")
    }
}

One of the devices must initiate the connection. Since the Discoverer has a callback for endpoint discovery, it makes sense for the phone to request the connection to the TV.

The phone asks for a connection supplying a `connectionLifecycleCallback` which is symmetric to the callback in the TV code.

val connectionLifecycleCallback = object : ConnectionLifecycleCallback() {
    override fun onConnectionInitiated(
        endpointId: String,
        connectionInfo: ConnectionInfo
    ) {
        Log.d(TAG, "Connection initialized to endpoint: $endpointId")
        // Make sure to authenticate using `connectionInfo.authenticationToken` before accepting
        Nearby.getConnectionsClient(context)
                .acceptConnection(endpointId, payloadCallback)
    }

    override fun onConnectionResult(
        endpointId: String,
        connectionResolution: ConnectionResolution
    ) {
        Log.d(TAG, "Connection result from endpoint: $endpointId")
        when (connectionResolution.status.statusCode) {
            ConnectionsStatusCodes.STATUS_OK -> {
                Log.d(TAG, "Connected to endpoint: $endpointId")
                otherDeviceEndpointId = endpointId
                waitingIndicator.visibility = View.GONE
                emailInput.editText?.isEnabled = true
                passwordInput.editText?.isEnabled = true

                Nearby.getConnectionsClient(this).stopDiscovery()
            }
            else -> {
                otherDeviceEndpointId = null
            }
        }
    }

    override fun onDisconnected(endpointId: String) {
        Log.d(TAG, "Disconnected from endpoint: $endpointId")
        otherDeviceEndpointId = null
    }
}

Once the connection is established, stop discovery to avoid keeping this battery-intensive operation running longer than needed. The example stops discovery after the connection is established, but it is possible for a user to leave the activity before that happens. Be sure to stop the discovery/advertising in onStop() on both the TV and phone.

override fun onStop() {
    super.onStop()
    Nearby.getConnectionsClient(this).stopDiscovery()
}




Just like a TV app, when you accept the connection you supply a payload callback. The callback listens for messages from the TV app such as the ACK described above to clean up the connection.

After the devices are connected, the user can use the keyboard and send their authentication information to the TV by calling `sendPayload()`.

fun sendCreditials() {

    val email = emailInput.editText?.text.toString()
    val password = passwordInput.editText?.text.toString()

    val creds = "$email:$password"
    val payload = Payload.fromBytes(creds.toByteArray())
    Log.d(TAG, "sending payload: $creds")
    if (otherDeviceEndpointId != null) {
        Nearby.getConnectionsClient(this)
                .sendPayload(otherDeviceEndpointId, payload)
    }
}

Ending the conversation

After the phone sends the payload to the TV (and the login is successful), there is no reason for the devices to remain connected. The TV can initiate the disconnection with a simple shutdown protocol.

The TV should send an ACK to the phone after it receives the credential payload.

val payloadCallback = object : PayloadCallback() {
    override fun onPayloadReceived(endpointId: String, payload: Payload) {
        if (payload.type == Payload.Type.BYTES) {
            payload.asBytes()?.let {
                val body = String(it)
                Log.d(TAG, "A payload was received: $body")
                // Validate that this payload contains the login credentials, and process them.

                val ack = Payload.fromBytes(ACK_PAYLOAD.toByteArray())
                Nearby.getConnectionsClient(context).sendPayload(endpointId, ack)
            }
        }
    }

    override fun onPayloadTransferUpdate(
        endpointId: String,
        update: PayloadTransferUpdate
    ) {    }
}

The phone should have a `PayloadCallback` that initiates a disconnection in response to the ACK. This is also a good time to reset the UI to show an authenticated state.

private val payloadCallback = object : PayloadCallback() {
    override fun onPayloadReceived(endpointId: String, payload: Payload) {
        if (payload.type == Payload.Type.BYTES) {
            payload.asBytes()?.let {
                val body = String(it)
                Log.d(TAG, "A payload was received: $body")

                if (body == ACK_PAYLOAD) {
                    waitingIndicator.visibility = View.VISIBLE
                    waitingIndicator.text = getString(R.string.login_successful)
                    emailInput.editText?.isEnabled = false
                    passwordInput.editText?.isEnabled = false
                    loginButton.isEnabled = false

                    Nearby.getConnectionsClient(this@MainActivity)
                        .disconnectFromEndpoint(endpointId)
                }
            }
        }
    }

    override fun onPayloadTransferUpdate(
        endpointId: String,
        update: PayloadTransferUpdate
    ) {    }
}

Security considerations

For security (especially since we're sending over sensitive information like login credentials), it's strongly recommended that you authenticate the connection by showing a code and having the user confirm that the two devices being connected are the intended ones -- without this, the connection established by Nearby Connection is encrypted but not authenticated, and that's susceptible to Man-In-The-Middle attacks. The documentation goes into greater detail on how to authenticate a connection.

Does your app offer a second screen experience?

There are many times when a user needs to supply input to a TV app. The Nearby API provides a way to offload the hardships of an onscreen-dpad-driven keyboard to an easy and familiar phone keyboard.

What use cases do you have where a second screen would simplify your user's life? Leave a comment or send me (@benjamintravels) or Varun (@varunkapoor, Team Lead for Nearby Connections) a tweet to continue the discussion.

17 Aug 2018 10:33pm GMT

The world of tech moves extremely quickly, and that's not exclusive to just phones. But fortunately for anyone that needs an easy way to keep up, there's an excellent service called SitePoint that makes it much easier. There are tons of ebooks, courses, and lessons here, and it'll cover everything from the infamous blockchain to development languages […]

Come comment on this article: [TA Deals] Learn everything tech related with a discounted lifetime SitePoint Premium subscription

17 Aug 2018 2:52pm GMT

Earlier this year Google rolled out a significant update to their Gmail platform. Many new features were added that built on work Google had done with other applications and were finally bringing over to the email platform. Some of the features, like the refreshed interface on the web, were available right away with other new […]

Come comment on this article: New Gmail confidential mode goes live

17 Aug 2018 2:30pm GMT

Huawei has confirmed that the pending launch of their Mate 20 series of smartphones will usher in a new era for processors as the company makes their new Kirin 980 available in a consumer product. The Kirin 980 is notable as it is produced using a 7nm manufacturing process. Huawei says the Mate 20s equipped […]

Come comment on this article: Huawei ready to launch 7nm Kirin 980 chip in the upcoming Mate 20

17 Aug 2018 12:32pm GMT

Over the past couple days, an update to Android 8.0 Oreo started rolling out to a subset of BlackBerry KEYone devices. That subset of devices is limited to those in the Canadian market. For owners in Canada, one bit of good news is that the update is hitting both unlocked and carrier devices. For everyone […]

Come comment on this article: Android Oreo starts a limited rollout on BlackBerry KEYone

17 Aug 2018 12:11pm GMT

WhatsApp offers a nifty little feature that allows users to back up their chats and image storage to Google Drive, which is very useful when changing devices. Whether you're upgrading or you've accidentally lost your phone, it's nice to have a backup so you don't lose everything with an old device. What makes this feature […]

Come comment on this article: WhatsApp chat backups won't count towards your Google Drive storage anymore

17 Aug 2018 2:09am GMT

There's been plenty of controversy over Android manufacturers copying the iPhone X in 2018. Specifically, the complaints have been over the notch in the display. I see both sides of that argument, too. It's hard not to see a little Apple inspiration in some of the designs, but on the other hand, I'm not against the […]

Come comment on this article: Motorola P30 or iPhone X? You decide.

17 Aug 2018 1:57am GMT

If you do any kind of creative work, you most likely know how popular Adobe's programs are. They're basically the standard for tons of hobbies and careers at this point, and we want to help you fully master some of those programs with the CC Training bundle. This bundle includes courses and lessons for several […]

Come comment on this article: [TA Deals] Pick your price for the Adobe Creative Cloud A-Z bundle!

16 Aug 2018 7:42pm GMT

Fast on the heels of HTC, Nokia, and Motorola confirming which of their handsets will be updated to Android Pie, Sony has officially announced which of its Xperia smartphones will jump on the bandwagon. As you might expect, most of Sony's heavy-hitters such as the Xperia XZ2 are present, but the update will also roll […]

Come comment on this article: Sony confirms Android Pie update to roll out to these Xperia handsets from November

16 Aug 2018 4:01pm GMT

In a week where we've seen both HTC and Nokia confirm which of their handsets would get updated to Android Pie (all of them in Nokia's case), we now have Motorola revealing which of its phones will follow suit. Android Pie brings features such as an improved Do Not Disturb mode, a revamped split-screen mode, […]

Come comment on this article: These Motorola smartphones are confirmed to get Android Pie update

16 Aug 2018 3:15pm GMT

After announcing Android Pie earlier this month, Google has formally unveiled Android Pie (Go edition) which the search giant claims offers a more streamlined, more secure version of Android that is suited to smartphones with modest specifications. With more than 200 devices running Android Go in over 120 countries at prices starting from a measly $30, […]

Come comment on this article: Google announces Android Pie (Go Edition) with more storage, faster booting, and extra security

16 Aug 2018 2:13pm GMT

Posted by Seang Chau, Vice President, Engineering

According to the World Health Organization¹, around 466 million people worldwide have disabling hearing loss. This number is expected to increase to 900 million people by the year 2050. Google is working with GN Hearing to create a new open specification for hearing aid streaming support on future versions of Android. Users with hearing loss will be able to connect, pair, and monitor their hearing aids so they can hear their phones loudly and clearly.

Hearing aid users expect a high quality, low latency experience with minimal impact on phone and hearing aid battery life. We've published a new hearing aid spec for Android smartphones: Audio Streaming for Hearing Aids (ASHA) on Bluetooth Low Energy Connection-Oriented Channels. ASHA is designed to have a minimal impact on battery life with low-latency while maintaining a high quality audio experience for users who rely on hearing aids. We look forward to continually evolving the spec to even better meet the needs of our users.

The spec details the pairing and connectivity, network topology, system architecture, and system requirements for implementing hearing aids using low energy connection-oriented channels. Any hearing aid manufacturer can now build native hearing aid support for Android.

The protocol specification is available here.

16 Aug 2018 1:00pm GMT

A few months ago Google started the process of transitioning Google Drive customers to their new Google One product. Google One is primarily a re-branding of Google Drive, though there are a couple new wrinkles involved with the revised platform. That stage of the transition appears to be complete as Google announced they are now […]

Come comment on this article: Google opens up Google One to the general public

15 Aug 2018 7:25pm GMT

Posted by Hoi Lam, Lead Developer Advocate, Wear OS by Google

Today we are announcing a new initiative to improve Wear app quality and their presentation in the Google Play Store. The Wear app review process, which has been in place since the launch of Android Wear 2.0, is currently optional. It will become mandatory for apps to be listed on the Wear OS by Google version of the Google Play Store from the following dates:

• New Wear apps: 1 October 2018
• Existing Wear apps: 4 March 2019.

The review process for mobile apps remains unchanged, and is independent of the Wear app review. Mobile app updates will not be blocked if they fail the Wear app review.

We hope this lightweight app review process will improve the quality of Wear app experiences across the wide range of devices available to your users. In addition, since screenshots are required for the Wear app review, this will improve the discovery and presentation of your Wear apps in the Google Play Store.

See a comprehensive list of review criteria here. The following are common issues we see during Wear app reviews:

• Support for different screen types - Wear OS by Google is available in both round and square screens, and some round devices also have a chin. Developers are advised to test on all screen types. If a physical device is unavailable, please use the Wear OS by Google emulator.
• Wear OS by Google app screenshot - To pass the review, the app needs to have at least one Wear OS app screenshot. To keep pre-release Wear apps private, the Google Play Store will not show the Wear screenshots unless the Wear App is in production or open testing. Currently, the Google Play Store only supports uploading one set of screenshots across all production and test versions. For existing Wear apps, we recommend developers keeping their production Wear app screenshots unchanged when uploading new open test or closed test Wear apps.

Opting out of app review for early prototypes

We understand that some developers need to experiment with their Wear apps in the early stages of app development, and a Wear app review at this stage might not be appropriate. In this case, developers have two options:

• Manually deploy Wear APKs to their users, or
• Leverage internal testing features via the Google Play console, which enables developers to test with up to 100 internal testing accounts.

Please note that the open test and closed test channels will be subject to Wear app review to help front-load the quality assurance process and to avoid leaving reviews to the last minute.

Thank you for your continuing support of Wear OS by Google.

15 Aug 2018 6:12pm GMT

It's no secret that the notched display has been the most popular trend of 2018 with just about everyone except Samsung and Sony jumping on the bandwagon, although Sony may well change its stance with the Xperia XZ3 that it is rumored to launch during IFA 2018 on August 30th. Huawei followed the notch trend […]

Come comment on this article: Huawei's Mate 20 could feature a 6.25-inch display with a notch

15 Aug 2018 3:11pm GMT

Remembering passwords is tough, especially in a day and age where websites are constantly getting breached and email addresses are leaking every other month. The good news is that you can use a good password manager that completely takes the frustration out of that process, and we're offering a killer deal on one of the […]

Come comment on this article: [TA Deals] Grab a cheap lifetime subscription to Sticky Password over 70% off!

15 Aug 2018 2:28pm GMT

The BlackBerry KEY2 is a pretty solid device with a price tag that isn't quite as brutal on your wallet as most flagship phones. But if that phone wasn't low-end enough for you, there's a BlackBerry KEY2 Lite Edition currently breaking cover that will help fill in some of BlackBerry's budget-friendly market. However, there's not […]

Come comment on this article: BlackBerry KEY2 LE leak shows a little bit of color

15 Aug 2018 2:15pm GMT

Posted by Shailen Tuli, DPE

Today we're releasing the source code for the official Google I/O 2018 for Android app.

The 2018 version constitutes a comprehensive rewrite of the app. For many years, the app has used a ContentProvider + SyncAdapter architecture. This year, we rewrote the app using Architecture Components and brought the code in sync with the Android team's current recommendations for building modern apps.

Architecture

We followed the recommendations laid out in the Guide to App Architecture for writing modular, testable and maintainable code when deciding on the architecture for the app. We kept logic away from Activities and Fragments and moved it to ViewModels. We observed data using LiveData and used the Data Binding Library to bind UI components in layouts to the app's data sources.

The overall architecture of the app can be summarized in this diagram:

We used a Repository layer for handling data operations. IOSched's data comes from a few different sources - user data is stored in Cloud Firestore (either remotely or in a local cache for offline use), user preferences and settings are stored in SharedPreferences, conference data is stored remotely and is fetched and stored in memory for the app to use - and the repository modules are responsible for handling all data operations and abstracting the data sources from the rest of the app. If we ever wanted to swap out the Firestore backend for a different data source in the future, our architecture allows us to do so in a clean way.

We implemented a lightweight domain layer, which sits between the data layer and the presentation layer, and handles discrete pieces of business logic off the UI thread. Examples.

We used Dagger2 for dependency injection and we heavily relied on dagger-android to abstract away boilerplate code.

We used Espresso for basic instrumentation tests and JUnit and Mockito for unit testing.

Firebase

The use of Firebase technologies has grown in the app as the Firebase platform has matured. The 2018 version uses the following Firebase components:

• Cloud Firestore is our source for all user data (events starred or reserved by a user). Firestore gave us automatic sync and also seamlessly managed offline functionality for us.
• Firebase Cloud Functions allowed us to run backend code. The reservations feature heavily depended on Functions checking a user's status (only attendees were allowed to make reservations), checking space availability and persisting reservation status in Firestore.
• Firebase Cloud Messaging let us inform the app about changes to conference data on our server. Conference data is mostly static, but it does change from time to time, especially after the keynote. The app has traditionally used a ping-and-fetch model when working with conference data, and we retained that usage this year.
• Remote Config helped us manage in-app constants. In previous years, we had found ourselves unable to inform users when data not directly related to the conference schedule - WiFi information, conference shuttle schedule, etc. - changed unexpectedly. Remote Config helped us update such values in a lightweight manner.

Kotlin

We made an early decision to rewrite the app from scratch to bring it in line with modern Android architecture. Using Kotlin for the rewrite was an easy choice: we loved Kotlin's expressive, concise, and powerful syntax; we found that Kotlin's support for safety features including nullability and immutability made our code more resilient; and we leveraged the enhanced functionality provided by Android Ktx extensions.

Material Design

At I/O 2018, the Material Design team announced Material Theming, giving apps much greater ability to customize Material Design to bring more of their product's brand. As we launched the app before Material Theming, we couldn't use all of the new components but we managed to sneak a couple in like the new Bottom App Bar with inset Floating Action Button and we were able to incorporate a lot of the conference's branding elements.

Future plans

The rewrite of the app brings the code in sync with Android's opinionated recommendations about building apps, and it resulted in a cleaner, more maintainable codebase. We'll continue working on the app, incorporating JetPack components as they become available and finding opportunities to showcase platform features that are good fits for the app. Developers can follow changes to the code on GitHub.

13 Aug 2018 5:23pm GMT

Posted by Purnima Kochikar, Director, Google Play, Apps & Games

On Monday we released Android 9 Pie. As we continue to push the Android platform forward, we're always looking to provide new ways to distribute your apps efficiently, help people discover and engage with your work, and improve the overall security of our ecosystem. Google Play has had a busy year so far with some big milestones around helping you reach more users, including:

• Shrinking download size: Android App Bundle & Dynamic Delivery has helped reduce app sizes by up to 65%, leading to increased downloads and fewer uninstalls.
• Helping improve quality: New tools in the Play Console have helped you reduce crash rates by up to 70%.
• Improving discovery: Improvements to the discovery experience have increased Google Play Store visits by 30% over the last 12 months.
• Keeping users safe: Google Play Protect scans more than 50 billion apps a day and Android API level 26 adoption requirements improve app security and performance.

Google Play is dedicated to helping you build and grow quality app businesses, reach the more than 2 billion Android devices globally and provide your users with better experiences. Here are some of the important areas we're prioritizing this year:

Innovative Distribution

We've added more testing tools to the popular Play Console to help developers de-risk app launches with internal and external test tracks and staged rollouts to get valuable early feedback. This year we've expanded the Start on Android program globally that provides developers new to Android additional guidance to optimize their apps before launch. Google Play Instant remains a huge bet to transform app discovery and improve conversions by letting users engage without the friction of installing. We're seeing great results from early adopters and are working on new places to surface instant experience, including ads, and making them easier to build throughout the year.

Improving App Quality

Google Play plays an important role helping developers understand and fix quality and performance issues. At I/O, we showcased how we expanded the battery, stability and rendering of Android vitals reporting to include app start time & permission denials, enabling developers to cut application not responding errors by up to 95%. We also expanded the functionality of automated device testing with the pre-launch report to enable games testing. Recently, we increased the importance of app quality in our search and discovery recommendations that has resulted in higher engagement and satisfaction with downloaded games.

Richer Discovery

Over the last year we've rolled out more editorial content and improved our machine learning to deliver personalized recommendations for apps and games that engage users. Since most game downloads come from browsing (as opposed to searching or deep linking into) the store, we've put particular focus on games discovery, with a new games home page, special sections for premium and new games, immersive video trailers and screenshots, and the ability to try games instantly. We've also introduced new programs to help drive app downloads through richer discovery. For example, since launching our app pre-registration program in 2016, we've seen nearly 250 million app pre-registrations. Going forward, we'll be expanding on these programs and others like LiveOps cards to help developers engage more deeply with their audience.

Expanding Commerce Platform

Google Play now collects payments in 150 markets via credit card, direct carrier billing (DCB), Paypal, and gift cards. Direct carrier billing is now enabled across 167 carriers in 64 markets. In 2018, we have focused on expanding our footprint in Africa and Latam with launches in Ghana, Kenya, Tanzania, Nigeria, Peru & Colombia. And users can now buy Google Play credit via gift cards or other means in more 800,000 retail locations around the world. This year, we also launched seller support in 18 new markets bringing the total markets with seller support to 98. Our subscription offering continues to improve with ML-powered fraud detection and even more control for subscribers and developers. Google Play's risk modeling automatically helps detect fraudulent transactions and purchase APIs help you better analyze your refund data to identify suspicious activity.

Maintaining a Safe & Secure Ecosystem

Google Play Protect and our other systems scan and analyze more than 50 billion apps a day to keep our ecosystem safe for users and developers. In fact, people who only download apps from Google Play are nine times less likely to download a potentially harmful app than those who download from other sources. We've made significant improvements in our ability to detect abuse-such as impersonation, inappropriate content, fraud, or malware-through new machine learning models and techniques. The result is that 99% of apps with abusive content are identified and rejected before anyone can install them. We're also continuing to run the Google Play Security Rewards Program through a collaboration with Hacker One to discover other vulnerabilities.

We are continually inspired by what developers build-check out #IMakeApps for incredible examples-and want every developer to have the tools needed to succeed. We can't wait to see what you do next!

09 Aug 2018 2:27am GMT

Posted by Vineet Tanwar, Business Development Manager, Google Play

In June, we announced the Indie Games Accelerator, a new four month program to help indie game startups from India, Pakistan and Southeast Asia supercharge their growth on Android. We have been truly impressed by the overwhelming responses we have received, and the creativity that indie game developers from these regions have to offer.

We had a great time going through the applications and playing the games which were submitted for review. Now, it's finally time to announce the inaugural class of startups selected for the program who we will mentor and coach over the next few months. Here they are:

Congratulations to the selected participants and a huge thanks to everyone that applied! Find out more about the program or express your interest in joining next class of Indie Games Accelerator.

How useful did you find this blogpost?

★ ★ ★ ★ ★

09 Aug 2018 1:00am GMT

Posted by James Lau, Product Manager (@jmslau)

When using the Java programming language, one of the most common pitfalls is trying to access a member of a null reference, causing a NullPointerException to be thrown. Kotlin offers protection against this by baking nullable and non-nullable types into the type system. This helps eliminate NullPointerExceptions from your code and improve your app's overall quality. When Kotlin code is calling into APIs written in the Java programming language, it relies on nullability annotations in those APIs to determine the nullability of each parameter and the return type. Unannotated parameters and return types are treated as platform types, which weakens the null-safety guarantee of Kotlin.

As part of yesterday's Android 9 announcement, we have also released a new Android SDK that contains nullability annotations for some of the most frequently used APIs. This will preserve the null-safety guarantee when your Kotlin code is calling into any annotated APIs in the SDK. Even if you are using the Java programming language, you can still benefit from these annotations by using Android Studio to catch nullability contract violations.

Not a breaking change

Normally, nullability contract violations in Kotlin result in compilation errors. But to ensure the newly annotated APIs are compatible with your existing code, we are using an internal mechanism provided by the Kotlin compiler team to mark the APIs as recently annotated. Recently annotated APIs will result only in warnings instead of errors from the Kotlin compiler. You will need to use Kotlin 1.2.60 or later.

Our plan is to have newly added nullability annotations produce warnings only, and increase the severity level to errors starting in the following year's Android SDK. The goal is to provide you with sufficient time to update your code.

How to use the "Kotlin-friendly" SDK

To get started, go to Tools > SDK Manager in Android Studio. Select Android SDK on the left menu, and make sure the SDK Platforms tab is open.

Use SDK Manager in Android Studio to install SDK for API Level 28 Revision 6

Check Android 8.+ (P) and click OK. This will install the Android SDK Platform 28 revision 6 if it is not already installed. After that, set your project's compile SDK version to API 28 to start using the new Android Pie SDK with nullability annotations.

Use the Project Structure Dialog to change your project's Compile Sdk Version to API 28

You may also need to update your Kotlin plugin in Android Studio if it's not already up-to-date. Make sure your Kotlin plugin version is 1.2.60 or later by going to Tools > Kotlin > Configure Kotlin Plugin Updates.

Once it's set up, your builds will start showing warnings if you have any code that violates nullability contracts in the Android SDK. An example of such a warning is shown below.

Sample warning from the Kotlin compiler when code violates a recently added nullability contract in the Android SDK.

You will also start seeing warnings in Android Studio's code editor if you call an Android API with the incorrect nullability. An example is shown below.

Android Studio warning about passing a null reference to a parameter annotated as a recently non-null type in the android.graphics.Path API.

Leveraging nullability annotations from the Java programming language

You can benefit from the new nullability annotations even if your code is in the Java programming language. By default, Android Studio will highlight any nullability contract violations with a warning, like the one below:

Android Studio showing a warning about nullability contract violation in code written in the Java programming language

To ensure that you have this inspection enabled, you can go to the IDE's settings page and search for "Constant conditions & exceptions" inspection and make sure that item is checked.

Use the Inspections page under Settings to ensure the Constant conditions & exceptions code inspection is enabled.

If you are using the Java programming language, nullability contract violations will not produce any compiler warning or error. Only the in-IDE code inspections are available to flag these issues.

You can also run code inspections across your entire project and see the aggregated results. Click on Analyze > Inspect Code… to start.

What's Next

The Android SDK API surface is very large, and we have only annotated a small percentage of the APIs so far - there is still lots of work remaining. Over the next several Android SDK releases, we will continue to add nullability annotations to the existing Android APIs, as well as making sure new APIs are annotated.

With the "Kotlin-friendly" Android SDK, the nullability annotations in AndroidX (part of the Jetpack family), and Android KTX, we are continuing to improve the Android APIs for developers using Kotlin. If you have not yet tried Kotlin, we encourage you to try it. Not only can Kotlin make your code more concise, it can also improve the stability of your apps.

Happy Kotlin-ing!

07 Aug 2018 5:23pm GMT

Posted by Dave Burke, VP of Engineering

After more than a year of development and months of testing by early adopters, we're ready to launch Android 9 Pie, the latest release of Android, to the world.

Android 9 harnesses the power of machine learning to make your phone smarter, simpler, and tailored to you. Read all about the new consumer features here. For developers, Android 9 includes many new ways to enhance your apps and build new experiences to drive engagement.

You've given us tons of feedback along the way--over a thousand bugs and feature requests--thank you! More than 140,000 of you tried our preview builds through the Android Beta program, and seven of our device maker partners also brought our Beta to their flagship devices, enabling users around the world to give their feedback too.

Today we're pushing the source code to Android Open Source Project (AOSP), and starting the Android 9 rollout to all Pixel users worldwide, with Android 9 coming to many more devices in the coming months.

We continue to move Android forward as the premier open platform for developers worldwide to build their businesses. With Android 9 -- together with the powerful new capabilities in Google Play for apps and games -- we're committed to helping you build great experiences, as well as reach and engage the right users safely and cost-effectively around the world.

What's in Android 9?

A smarter smartphone, with machine learning at the core

Android 9 helps your phone learn as you use it, by picking up on your preferences and adjusting automatically. Everything from helping users get the most out of their battery life to surfacing the best parts of the apps they use all the time, right when they need it most, Android 9 keeps things running smoother, longer.

Adaptive Battery

We partnered with DeepMind on a feature called Adaptive Battery that uses machine learning to prioritize system resources for the apps the user cares about most. If your app is optimized for Doze, App Standby, and Background Limits, Adaptive Battery should work well for you right out of the box. If you haven't yet taken optimized your app, make sure to check out the details in the power documentation to see how it works.

Slices

Slices can help users perform tasks faster by enabling engagement outside of the fullscreen app experience. It does this by using UI templates that can display rich, dynamic, and interactive content from your app from within the Google Search app and later in other places like the Google Assistant. You can learn more about building Slices to enhance your app here.

App Actions

App Actions is a new way to raise the visibility of your app and drive engagement. Actions take advantage of machine learning to surface your app to the user at just the right time, based on your app's semantic intents and the user's context.

We'll be sharing more details in the coming weeks on registering your app to handle one or more user intents, so your apps can be enabled for App Actions and surfaced across multiple Google and Android surfaces in response to user queries.

Text Classifier and Smart Linkify

We've extended the ML models that identify entities in content or text input to support more types like Dates and Flight Numbers through the TextClassifier API. Smart Linkify lets you take advantage of the TextClassifier models through the Linkify API, including enriched options for quick follow-on user actions. Smart Linkify also delivers significant improvements in accuracy of detection as well as performance.

Neural Networks API 1.1

Android 9 adds an updated version of the Neural networks API, to extend Android's support for accelerated on-device machine learning. Neural Networks 1.1 adds support for nine new ops -- Pad, BatchToSpaceND, SpaceToBatchND, Transpose, Strided Slice, Mean, Div, Sub, and Squeeze. A typical way to take advantage of the APIs is through TensorFlow Lite.

Getting the most from your phone -- more easily

We're excited about making your smartphone more intelligent. But it's also important that the technology fades to the back for users. In Android 9, we've evolved Android's UI to be simpler and more approachable -- for developers, these changes help improve the way users find, use, and manage your apps.

New system navigation

Android 9 introduces a new system navigation that we've been working on for more than a year. The new design helps make Android's multitasking more approachable and makes discovering apps much easier. You can swipe up from anywhere to see full-screen previews of recently used apps and simply tap to jump back into one of them.

Display cutout

Now your app can take full advantage of the latest edge-to-edge screens through display cutout support in Android 9. For most apps, supporting display cutout is seamless, with the system managing status bar height to separate your content from the cutout. If you have immersive content, you can use the display cutout APIs to check the position and shape of the cutout and request full-screen layout around it. To help with development and testing, we've added a Developer Option that simulates several cutout shapes on any device.

Apps with immersive content can display content fullscreen on devices with a display cutout.

Notifications and smart reply

Android 9 makes notifications even more useful and more actionable. Messaging apps can take advantage of the new MessagingStyle APIs to show conversations, attach photos and stickers, and even suggest smart replies. You'll soon be able to use ML Kit to generate smart reply suggestions for your app.

MessagingStyle notifications with conversations and smart replies [left], images and stickers [right].

Text Magnifier

In Android 9 we've added a Magnifier widget to improve the user experience of selecting text. The Magnifier widget lets users precisely position the cursor or the text selection handles by viewing zoomed text through a draggable pane. You can attach it to any view that is attached to a window, so you can use it in custom widgets or during custom text-rendering. The Magnifier widget can also provide a zoomed-in version of any view or surface, not just text.

Check out our recent blog post for more about this and other Text features, such as PrecomputedText and line height and baseline text alignment.

Security and privacy for users

Biometric prompt

With a range of biometric sensors in use for authentication, we've made the experience more consistent across sensor types and apps. Android 9 introduces a system-managed dialog to prompt the user for any supported type of biometric authentication. Apps no longer need to build their own dialog--instead they use the BiometricPrompt API to show the standard system dialog. In addition to Fingerprint (including in-display sensors), the API supports Face and Iris authentication.

If your app is drawing its own fingerprint auth dialogs, you should switch to using the BiometricPrompt API as soon as possible. See this post for more information.

Protected Confirmation

Android 9 introduces Android Protected Confirmation, which uses the Trusted Execution Environment (TEE) to guarantee that a given prompt string is shown and confirmed by the user. Only after successful user confirmation will the TEE then sign the prompt string, which the app can verify.

Stronger protection for private keys

We've added StrongBox as a new KeyStore type, providing API support for devices that provide key storage in tamper-resistant hardware with isolated CPU, RAM, and secure flash. You can set whether your keys should be protected by a StrongBox security chip in your KeyGenParameterSpec.

DNS over TLS

Android 9 adds built-in support for DNS over TLS, automatically upgrading DNS queries to TLS if a network's DNS server supports it. Users can manage DNS over TLS behavior in a new Private DNS Mode in Network & internet settings. Apps that perform their own DNS queries can use a new API, LinkProperties.isPrivateDnsActive(), to check the DNS mode. More in this post.

HTTPS by default

As part of a larger effort to move all network traffic away from cleartext (unencrypted HTTP) to websites secured with TLS (HTTPS), we're changing the defaults for Network Security Configuration to block all cleartext traffic. You'll now need to make connections over TLS, unless you explicitly opt-in to cleartext for specific domains. See the details here.

Compiler-based security mitigations

In Android 9 we've expanded our use of compiler-level mitigations to harden the platform through run-time detection of dangerous behavior. Control Flow Integrity (CFI) techniques help to prevent code-reuse attacks and arbitrary code execution. In Android 9 we've greatly expanded CFI usage within the media framework and other security-critical components, such as NFC and Bluetooth. We've also introduced CFI kernel support into the Android common kernel when building with LLVM.

We've also expanded our use of Integer overflow sanitizers to mitigate memory-corruption and information-disclosure vulnerabilities. We've prioritized sanitizers in libraries with past vulnerabilities or where complex untrusted input is processed, such as libui, libnl, libmediaplayerservice and others. See this post for details.

Privacy for users

Android 9 safeguards privacy in a number of new ways. The system now restricts access to mic, camera, and all SensorManager sensors from apps that are idle. While your app's UID is idle, the mic reports empty audio and sensors stop reporting events. Cameras used by your app are disconnected and will generate an error if the app tries to use them. In most cases, these restrictions should not introduce new issues for existing apps, but we recommend removing these requests from your apps.

Android 9 also gives the user control over access to the platform's build.serial identifier by putting it behind the READ_PHONE_STATE permission. To access the build.serial identifier, you should use the Build.getSerial() method.

Read more about all of the privacy changes here.

New experiences in camera, audio, and graphics

Multi-camera API and other camera updates

With Android 9 you can now open streams from two or more physical cameras simultaneously on devices that support the multi-camera API. On devices with either dual-front or dual-back cameras, you can create innovative features not possible with just a single camera, such as seamless zoom, bokeh, and stereo vision. The API also lets you call a logical or fused camera stream that automatically switches between two or more cameras.

Other improvements in camera include new Session parameters that help to reduce delays during initial capture, and Surface sharing that lets camera clients handle various use-cases without the need to stop and start camera streaming. We've also added APIs for display-based flash support and access to OIS timestamps for app-level image stabilization and special effects.

HDR VP9 Video and HEIF image compression

Android 9 adds built-in support for HDR VP9 Profile 2, so you can now deliver HDR-enabled movies to your users on HDR-capable devices.

We're excited to add HEIF (heic) image encoding to the platform. HEIF is a popular format for photos that improves compression to save on storage and network data. With platform support on Android 9 devices, it's easy to send and utilize HEIF images from your backend server. Once you've made sure that your app is compatible with this data format for sharing and display, give HEIF a try as an image storage format in your app. You can do a jpeg-to-heic conversion using ImageDecoder or BitmapFactory to obtain a bitmap from jpeg, and you can use HeifWriter in the AndroidX library to write HEIF still images from YUV byte buffer, Surface, or Bitmap.

Enhanced audio with Dynamics Processing

The Dynamics Processing API lets you use a new audio effect to isolate specific frequencies and lower loud or increase soft sounds to enhance the acoustic quality of your app. For example, you can improve the sound of someone who speaks quietly in a loud, distant or otherwise acoustically challenging environment. The API gives you access to a multi-stage, multi-band dynamics processing effect that includes a pre-equalizer, a multi-band compressor, a post-equalizer and a linked limiter.

ImageDecoder for bitmaps and drawables

An ImageDecoder API gives you an easier way to decode images to bitmaps or drawables. You can create a bitmap or drawable from a byte buffer, file, or URI. The API offers several advantages over BitmapFactory, including support for exact scaling, single-step decoding to hardware memory, support for post-processing in decode, and decoding of animated images. You can read more here.

Connectivity and location

Wi-Fi RTT for indoor positioning

Android 9 lets you build indoor positioning features into your apps through platform support for the IEEE 802.11mc Wi-Fi protocol -- also known as Wi-Fi Round-Trip-Time (RTT). On Android 9 devices with hardware support, location permission, and location enabled, your apps can use RTT APIs to measure the distance to nearby Wi-Fi Access Points (APs). The device doesn't need to connect to the APs to use RTT, and to maintain privacy, only the phone is able to determine the distance, not the APs.

Knowing the distance to 3 or more APs, you can calculate the device position with an accuracy of 1 to 2 meters. With this accuracy you can support use-cases like in-building navigation; fine-grained location-based services such as disambiguated voice control (e.g. 'Turn on this light'); and location-based information (e.g. 'Are there special offers for this product?').

Data cost sensitivity in JobScheduler

JobScheduler is Android's central service to help you manage scheduled tasks or work across Doze, App Standby, and Background Limits. In Android 9, JobScheduler handles network-related jobs better for the user, coordinating with network status signals provided separately by carriers. Jobs can now declare their estimated data size, signal prefetching, and specify detailed network requirements-carriers can report networks as being congested or unmetered. JobScheduler then manages work according to the network status. For example, when a network is congested, JobScheduler might defer large network requests. When unmetered, it can run prefetch jobs to improve the user experience, such as prefetching headlines.

Open Mobile API for NFC payments and secure transactions

Android 9 adds an implementation of the GlobalPlatform Open Mobile API to Android. On supported devices, apps can use the OMAPI API to access secure elements (SE) to enable smart-card payments and other secure services. A hardware abstraction layer (HAL) provides the underlying API for enumerating the variety of Secure Elements (eSE, UICC, and others) available.

Performance for apps

ART performance

Android 9 brings performance and efficiency improvements to all apps through the ART runtime. We've expanded ART's use of execution profiles to optimize apps and reduce the in-memory footprint of compiled app code. ART now uses profile information for on-device rewriting of DEX files, with reductions up to 11% across a range of popular apps. We expect these to correlate closely with reductions in system DEX memory usage and faster startup times for your apps.

Optimized for Kotlin

Kotlin is a first-class language on Android, and if you haven't tried it yet, you should! We've made an enduring commitment to Kotlin in Android and continue to expand support including optimizing the performance of Kotlin code. In Android 9, you'll see the first results of this work--we've improved several compiler optimizations, especially those that target loops, to extract better performance. We're also continuing to work in partnership with JetBrains to optimize Kotlin's generated code. You can get all of the latest Kotlin performance improvements just by keeping Android Studio's Kotlin plugin up-to-date.

Today, we are also releasing an update to the Android 9 - API 28 SDK (rev. 6), which contains nullability annotations in some of the most frequently used APIs. We'll provide more details about this in an upcoming post.

Modern Android

As part of Android 9 we are modernizing the foundations of Android and the apps that run on it, as part of our deep, sustained investments in security, performance, and stability.

As we announced last year, Google Play will require all app updates to target Android Oreo (targetSdkVersion 26 or higher) by November 2018. In line with that, if your app targets a platform earlier than Android 4.2 (API level 17), users installing it will see a warning dialog the first time your app is run. Here's a checklist of resources for help and support as you migrate -- we're looking forward to seeing your apps getting the most from modern Android.

Get your apps ready for Android 9!

With Android 9 coming to Pixel users starting today, and to other devices in the months ahead, it's important to test your app for compatibility as soon as possible. Just install your current app from Google Play on a device or or emulator running Android 9. As you work through the flows, make sure your app runs and looks great, and that it handles the Android 9 behavior changes properly.

Also watch for uses of non-SDK interfaces in your app. Android 9 restricts access to selected non-SDK interfaces, so you should reduce your reliance on them. See our recent post for details.

After you've made any necessary updates, we recommend publishing to Google Play right away. without changing the app's platform targeting. This lets you ensure a great experience for Android 9 users while you work on enhancing your app with Android 9 APIs and targeting.

Enhance your app with Android 9 features and APIs

When you're ready, dive into Android 9 and build with the new features and APIs in Android 9.

To get started, just download the official API 28 SDK and the latest tools and emulator images into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28. When you change your targeting, make sure your app supports all of the applicable behavior changes.

As soon as you're ready, publish your APK updates to Google Play. A common strategy is to use Google Play's beta testing feature to get early feedback from a small group of users and then do a staged rollout to production.

Visit the Android 9 site for details and developer documentation. Also check out this video and the Google I/O Android Playlist for more on what's new in Android 9 for developers.

Coming to a device near you

Starting today, an over-the-air update to Android 9 will begin rolling out to Pixel phones. And devices that participated in the Beta program from Sony Mobile, Xiaomi, HMD Global, Oppo, Vivo, OnePlus, and Essential, as well as all qualifying Android One devices, will receive this update by the end of this fall! We are also working with a number of other partners to launch or upgrade devices to Android 9 this year.

As always, the system images for Pixel devices are available here for manual flash and download. If you're looking for the Android 9 source, you'll find it here in the Android Open Source Project repository under the Android 9 branches.

What's next?

Now that we've reached the official release, we're bringing the Developer Preview to a close. We'll soon be closing the Developer Preview issue tracker to new issues, so if you have feedback, feel free to file a new issue against Android 9 in the AOSP issue tracker.

Thanks again to the many developers and early adopters who participated in the Android 9 Developer Preview and public beta. Your contributions have been critical to making the Android 9 platform a great one for developers and consumers.

06 Aug 2018 5:05pm GMT

Posted By Megan Potoski, Product Manager, Android System UI

Smartphones are quickly moving towards smaller bezels and larger aspect ratios. On these devices, display cutouts are a popular way to achieve an edge-to-edge experience while providing space for important sensors on the front of the device. There are currently 16 cutout devices from 11 OEMs already released, including several Android P beta devices, with more on the way.

These striking displays present a great opportunity for you to showcase your app. They also mean it's more important than ever to make sure your app provides a consistently great experience across devices with one or two display cutouts, as well as devices with 18:9 and larger aspect ratios.

Examples of cutout devices: Essential PH-1 (left) and Huawei P20 (right).

Make your app compatible with display cutouts

With many popular and upcoming devices featuring display cutouts, what can you do to make sure your app is cutout-ready?

The good news is, for the most part your app should work as intended even on a cutout device. By default, in portrait mode with no special flags set, the status bar will be resized to be at least as tall as the cutout and your content will display in the window below. In landscape or fullscreen mode, your app window will be letterboxed so that none of your content is displayed in the cutout area.

However, there are a few areas where your app could have issues on cutout devices.

• Watch out for any sort of hard-coding of status bar height -- this will likely cause problems. If possible, use WindowInsetsCompat to get status bar height.
• In fullscreen, be careful to consider when to use window vs. screen coordinates, as your app will not take up the whole screen when letterboxed. For example, if you use MotionEvent.getRawX/Y() to get screen coordinates for touch events, make sure to transform them to the view's coordinates using getLocationOnScreen().
• Pay special attention to transitions in and out of fullscreen mode.

Here are a few guidelines describing what issues to look out for and how to fix them.

Take advantage of the cutout area

Rendering your app content in the cutout area can be a great way to provide a more immersive, edge-to-edge experience for users, especially for content like videos, photos, maps, and games.

An example of an app that has requested layout in the display cutout.

In Android P we added APIs to let you manage how your app uses the display cutout area, as well as to check for the presence of cutouts and get their positions.

You can use layoutInDisplayCutoutMode, a new window layout mode, to control how your content is displayed relative to the cutout. By default, the app's window is allowed to extend into the cutout area if the cutout is fully contained within a system bar. Otherwise, the window is laid out such that it does not overlap with the cutout. You can also set layoutInDisplayCutoutMode to always or never render into the cutout. Using SHORT_EDGES mode to always render into the cutout is a great option if you want to take advantage of the full display and don't mind if a bit of content gets obscured by the cutout.

If you are rendering into the cutout, you can use getDisplayCutout() to retrieve a DisplayCutout that has the cutout's safe insets and bounding box(es). These let you check whether your content overlaps the cutout and reposition things if needed.

<style name="ActivityTheme">
  <item name="android:windowLayoutInDisplayCutoutMode">
    default/shortEdges/never
  </item>
</style>

Attribute for setting layoutInDisplayCutoutMode from the Activity's theme.

For devices running Android 8.1 (API 27), we've also back-ported the layoutInDisplayCutoutMode activity theme attribute so you can control the display of your content in the cutout area. Note that support on devices running Android 8.1 or lower is up to the device manufacturer, however.

To make it easier to manage your cutout implementation across API levels, we've also added DisplayCutoutCompat in the AndroidX library, which is now available through the SDK manager.

For more about the display cutout APIs, take a look at the documentation.

Test your app with cutout

We strongly recommend testing all screens and experiences of your app to make sure that they work well on cutout devices. We recommend using one of the Android P Beta Devices that features a cutout, such as the Essential PH-1.

If you don't have a device, you can also test using a simulated cutout on any device running Android P or in the Android Emulator. This should help you uncover any issues that your app may run into on devices with cutouts, whether they are running Android 8.1 or Android P.

What to expect on devices with display cutouts

Android P introduces official platform support for display cutouts, with APIs that you can use to show your content inside or outside of the cutout. To ensure consistency and app compatibility, we're working with our device manufacturer partners to mandate a few requirements.

First, devices must ensure that their cutouts do not negatively affect apps. There are two key requirements:

• In portrait orientation, with no special flags set, the status bar must extend to at least the height of the cutout.
• In fullscreen or landscape orientation, the entire cutout area must be letterboxed.

Second, devices may only have up to one cutout on each short edge of the device. This means that:

• You won't see multiple cutouts on a single edge, or more than two cutouts on a device.
• You won't see a cutout on the left or right long edge of the device.

Within these constraints, devices can place cutouts wherever they want.

Special mode

Some devices running Android 8.1 (API level 27) or earlier may optionally support a "special mode" that lets users extend a letterboxed fullscreen or landscape app into the cutout area. Devices would typically offer this mode through a toggle in the navigation bar, which would then bring up a confirmation dialog before extending the screen.

Devices that offer "special mode" allow users to optionally extend apps into the cutout area if supported by the app.

If your app's targetSdkVersion is 27 or higher, you can set the layoutInDisplayCutoutMode activity theme attribute to opt-out of special mode if needed.

Don't forget: larger aspect ratios too!

While you are working on cutout support, it's also a great time to make sure your app works well on devices with 18:9 or larger aspect ratios, especially since these devices are becoming increasingly common and can feature display cutouts.

We highly encourage you to support flexible aspect ratios so that your app can leverage the full display area, no matter what device it's on. You should test your app on different display ratios to make sure it functions properly and looks good.

Here are some guidelines on screens support to keep in mind as you are developing, also refer to our earlier post on larger aspect ratios for tips on optimizing. If your app can't adapt to the aspect ratios on long screens, you can choose to declare a max aspect ratio to request letterboxing on those screens.

Thanks for reading, and we hope this helps you deliver a delightful experience to all your users, whatever display they may have!

30 Jul 2018 8:04pm GMT

Posted by Aurimas Liutikas, software engineer on AndroidX team

AndroidX (previously known as Android Support Library) started out as a small set of libraries intended to provide backwards compatibility for new Android platform APIs and, as such, its development was strictly tied to the platform. As a result, all work was done in internal Google branches and then pushed to the public Android Open Source Project (AOSP) together with the platform push. With this flow, external contributions were limited to a narrow window of time where the internal and AOSP branches were close in content. On top of that, it was difficult to contribute -- in order to do a full AndroidX build and testing, external developers had to check out >40GB of the full Android platform code.

Today, the scope of AndroidX has expanded dramatically and includes libraries such as AppCompat for easier UI development, Room for database management, and WorkManager for background work. Many of these libraries implement higher-level abstractions and are less tied to new revisions of the Android platform, and all libraries are designed with backwards compatibility in mind from the start. Several libraries, such as RecyclerView and Fragment, are purely AndroidX-side implementations with few ties to the platform.

Starting a little over two years ago, we began a process of unbundling -- moving AndroidX out of Android platform builds into its own separate build. We had to do a great deal of work, including migrating our builds from make to Gradle as well as migrating all of our API tracking tools and documentation generation out of the platform build. With that process completed, we reached a point where a developer can now check out a minimal AndroidX project, open it in Android Studio, and build using the public SDK and public Android Gradle Plugin.

The Android developer community has long expressed a desire to contribute more easily to AndroidX; however, this was always a challenge due to the reasons described above. This changes today: AndroidX development is moving to public AOSP. That means that our primary feature development (except for top-secret integrations with the platform 😀) and bug fixes will be done in the open using the r.android.com Gerrit review tool and changes will be visible in the aosp/androidx-master-dev branch.

We are making this change to give better transparency to developers; it gives developers a chance to see features and bug fixes implemented in real-time. We are also excited about receiving bug fix contributions from the community. We have written up a short guide on how to go about contributing a patch.

In addition to regular development, AOSP will be a place for experimentation and prototyping. You will see new libraries show up in this repository; some of them may be removed before they ship, change dramatically during pre-alpha development, or merge into existing libraries. The general rule is that only the libraries on maven.google.com are officially ready for external developer usage.

Finally, we are just getting started. We apologize for any rough edges that you might have when contributing to AndroidX, and we request your feedback via the public AndroidX tracker if you hit any issues.

26 Jul 2018 4:15pm GMT

Posted By Dave Burke, VP of Engineering

Android P is almost here! As we put the finishing touches on the new platform, today we're bringing you Android P Beta 4.

Beta 4 is the last preview milestone before we launch the official Android P platform later this summer. Take this opportunity to test your apps and publish updates, to make sure you offer a great experience for users transitioning to Android P!

What's in this update?

Today's Beta 4 update includes a release candidate build with final system behaviors and the official Android P APIs (API level 28), available since Beta 2. It includes everything you need to wrap up your testing in time for the upcoming official Android P release.

Get your apps ready for Android P

With the consumer launch coming soon, it's important to test your app for compatibility with Android P. Just install your current app from Google Play on an Android P Beta device or emulator. As you work through the flows, make sure your app runs and looks great, and that it handles the Android P behavior changes properly.

Also watch for uses of non-SDK interfaces in your app. Android P restricts access to selected non-SDK interfaces, so you should reduce your reliance on them. See our recent post for details..

After you've made any necessary updates, we recommend publishing to Google Play right away without changing the app's platform targeting. This lets you ensure a great experience for Android P users while you work on enhancing your app with Android P APIs and targeting.

Enhance your app with Android P features and APIs

When you're ready, dive into Android P and learn about the new features and APIs that you can use in your apps, like multi-camera support, display cutout, enhanced notifications, ImageDecoder, TextClassifier, and others.

To build with the new APIs, just download the official API 28 SDK and tools into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28. When you change your targeting, make sure your app supports all of the applicable behavior changes.

As soon as you're ready, publish your APK updates that are compiled against, or optionally targeting, API 28. A common strategy is to use Google Play's beta testing feature to get early feedback from a small group of users and then do a staged rollout to production.

Visit the Developer Preview site for details and documentation. Also check out this video and the Google I/O Android playlist for more on what's new in Android P for developers.

How do I get Beta 4?

It's easy - you can get Android P Beta 4 on Pixel devices by enrolling here. If you're already enrolled in our Android Beta program, you'll automatically get the Beta 4 update soon. As always, downloadable system images for Pixel devices are also available. Partners who are participating in the Android P Beta program will also be updating their devices to Beta 4 over the coming weeks.

What's next?

Stay tuned for the official Android P launch coming soon! You can continue to share your feedback or requests in the meantime, and feel free to use our hotlists for platform issues, app compatibility issues, and third-party SDK issues.

Thanks for your feedback so far, and thank you to everyone who participated in our recent Reddit AMA on r/androiddev!

25 Jul 2018 5:09pm GMT

Posted by Tom Greenaway, Senior Partner Developer Advocate

Last year we announced that starting from August 2018 Google Play will require all new apps and games to target a recent Android API level - set to API level 26 (Android 8.0 Oreo), or higher. Additionally, this requirement will extend to updates for existing apps and games starting from November 2018.

Every new Android version introduces changes that bring significant security and performance improvements - and enhance the user experience of Android overall. Updating your games to target the latest API level ensures that your users can benefit from these improvements, while still allowing your games to run on older Android versions.

Simple next steps:

• Install the Android 8.0 Oreo SDK (API level 26) via Android Studio by navigating to (Tools > Android > SDK Manager > Android SDK > SDK Platforms).
• Update your game to target API level 26 and see whether your game has any incompatibilities or issues as soon as possible. Update any external dependencies as necessary. Learn more about the incremental changes between versions of Android here.
• If you are using an advertising network, SDK or plugin which is incompatible with API level 26, reach out to your contacts and find out their timeline for supporting target API level 26. The sooner they're aware of these changes the better.
• If you build your game with Unity, support for target API 26 is built into Unity 5.6.6 and beyond. Simply ensure the latest target API level is selected in your Android build settings for Unity (Build Settings > Android > Player Settings). For versions of Unity 5.6.5 and prior, consult this documentation which includes a workaround for versions dating back to 4.3.
• For games built with Unreal, check your Android platform settings has the "Target SDK Version" set to 26.
• If you use Cocos2D-X, check the target API level in the gradle.properties file that is generated.

Significant changes to be aware of:

• Since API 23, we have required permissions be requested at runtime which helps streamline the app install process.
• Since API 24, apps can no longer dynamically link against non-NDK libraries. If your app (including third-party static libraries) contains native code, you should only be using public NDK APIs.
• If your game uses Android push notifications, the Google Play Services SDK in your game will need to be updated to version 10.2.1 or above for your game to support API level 26.
• If your game uses opaque binary blobs (OBB), then your game must check if it can access the directory before attempting to access the OBB files themselves. We recommend explicitly requesting permission for access using the Runtime Permissions API, and gracefully handling cases wherein the permission is not granted. Additionally, add an entry in the manifest for the external storage access:
  

  <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
  

Moving ahead

Remember, updating the target API level is just the first step - make sure your game is compatible with the behavior changes between your current target API level and API level 26. Check out further guidance on the changes in past versions of Android to help in your migration process. These policy changes are important for moving the Android ecosystem forward and keeping it healthy for our users - and yours.

How useful did you find this blog post?

★ ★ ★ ★ ★

20 Jul 2018 4:55pm GMT

Posted by Neto Marin - Actions on Google Developer Advocate

There are millions of apps in the Android ecosystem, so helping yours get discovered can require some investment. Your app needs to offer something that differentiates it from other similar apps to stand out to users.

Building a companion Action is a fast and simple way to increase your Android app's potential reach by creating a new entrypoint from devices covered by the Google Assistant. This lets you bring your services to users without needing to install anything through voice, and can bring people into your app when it can provide more value.

Your companion Action complements your Android app's experience by offering some of your services through the Google Assistant, which is available on more than 500 million devices including speakers, phones, cars, headphones, and more. Creating an Action provides a frictionless way for users to start engaging with your services wherever the Google Assistant is available.

Creating an Action for the Assistant will extend your brand presence, bringing your services to new devices and contexts as users interact with the Google Assistant.

Feature what your app does better

It is probably a mistake to try to rewrite all of your Android app as a conversational Action, since voice is a different modality with different constraints and usage patterns. Instead, you should start by selecting the most important or popular features in your app that translate well into a voice context and can be more easily accomplished there. Then, you can create your conversational experience to offer these features on Google Assistant devices. Check out the Conversation design site, which has several articles and guides about how to create a great voice UI.

Let's take a look at a hypothetical example. Imagine you have a mobile commerce app. Some features include searching for products, navigating to different categories, adding payment information, and checking out. You could build an Action for the Assistant with most of the same functionality, but we encourage you to look for what makes the most sense in a conversational experience.

In this case, your Action could focus on everything that a user would want to know after they've purchased a product through your Android app or web page. You could offer a quick way to get updates about a purchase's status (if you provide different states for payment/purchase process) and shipment information, or provide an interface for re-ordering a user's favorite products. Then, your users would be able to ask something like, "Hey Google, ask Voice Store about my last purchase."

Or, to reach users who have never made a purchase before, you could create an Action to offer exciting deals for common products. For example, you could create an Action that is invoked with, "Hey Google, ask Voice Store what are the deals on TVs today".

As you can see, starting with a "hero" use case for your Action is an exciting way to introduce conversational features that complement your Android app, and it will take less time than you think.

At Google I/O 2018, we presented a talk, "Integrating your Android apps with the Google Assistant" which contains more details and examples for developers.

Delivering user's purchases across surfaces

In-app purchases, subscriptions, and one-time products have proven successful for Android developers when it comes to monetization, allowing developers to offer different kinds of digital goods and additional value for paying users. These types of monetization are proven to drive user conversion and make the app more profitable.

Google Play Billing offers a series of tools, APIs, and documentation to help developers manage the subscription life-cycle, build server-side validation, and much more. If you are new to in-app billing, check out the Google Play Billing Overview page.

Now, Android developers can expand where users can access these goods or upgraded experiences by offering them through Actions, as well. This expansion is accomplished by honoring the user's entitlements on Google Play across different surfaces and devices, reaching users when they can't (or don't want to) use an app, like while cooking or driving.

For non-Android platforms, you'll need to ask your users to link their accounts. You can then use your user's account history to identify what purchases they've made on other surfaces.

Check the Accessing Digital Purchases page for a step-by-step guide on how to enable access to the user's purchases and request and parse the purchase data.

What's next?

If you are not familiar with Actions on Google yet, start by checking out our overview page, which describes the platform in detail and tells you all you need to know to create your Actions for the Google Assistant.

Stay tuned for more posts about how to improve your Android app experience with Actions on Google.

Thanks for reading!

10 Jul 2018 4:43pm GMT

Posted by Jamal Eason, Product Manager, Android

Since the major revamp of the Android Emulator two years ago, we have focused on delivering a fast and feature-rich emulator to help you build great app experiences for users. Today, the Android Emulator is the top device deployed to from Android Studio - more than 2x over physical Android devices. We are humbled to hear from many of you that the Android Emulator has come a long way, but we are not done yet.

Making the Android Emulator faster is one of the top priorities for the Android Studio team. Over the last few releases, we have launched quick boot & emulator snapshots for quickly starting and resuming emulator sessions in under 2 seconds. Up until now, our emulator experience has almost universally worked on macOS^® and Linux computers. But for users of Microsoft^® Windows^® or the Microsoft^® Hyper-V^™ platform, our hardware accelerated speed enhancements for the Android Emulator only worked with computers with Intel^® processors. Support for AMD^® processors and Microsoft Hyper-V hypervisor are two long-standing user requests from the Android developer community that we are happy to address with this Android Emulator update.

Today, you can download the latest Android Emulator release, which is enabled to run x86 based Android Virtual Devices (AVD) on computers that use AMD processors. This exciting update makes the Android Emulator more accessible to a new set of Android app developers that were previously limited to software emulation, but can now have hardware accelerated performance. Moreover, for those of you who use Hyper-V to run your local app backend, the Android Emulator can now also coexist with other Hyper-V-backed applications on Windows^® 10.

Thanks to a new Microsoft Windows Hypervisor Platform (WHPX) API and recent open-source contributions from Microsoft, even more Android app developers can take advantage of all the speed improvements and features in the Android Emulator.

Android Emulator running on Windows 10 with AMD Processor Screenshot Configuration: Asus ROG Strix GL 702ZC, Processor: AMD^® Ryzen^™ 7 1700 Processor, Chipset: AMD 5350, Graphics: AMD^® Radeon^™ RX580

Support for these technologies was initially available in the v27.3.8 Android Emulator canary release and today we are releasing this set of preview features (AMD processor & Hyper-V support) on the stable channel for more feedback. Alongside this update, we have added additional speed improvements in loading emulator snapshots for those developers using the Intel^® Hardware Accelerated Execution Manager (HAXM).

How to use

Linux

If you use Linux for Android app development, the Android Emulator will continue to use the native Kernel-based Virtual Machine (KVM) hypervisor for both Intel and AMD based computers for a fast and performant virtualization solution. An update to the v27.3.8 Android Emulator will offer you the new snapshots UI along with improvements to performance, reliability and resource usage.

macOS

For OS X v10.10 Yosemite and higher, the Android Emulator uses the built-in Hypervisor.Framework by default, and falls back to using the Intel Hardware Accelerated Execution Manager (HAXM) if Hypervisor.Framework fails to initialize (such as when running on OS X v10.9 or earlier). Once you update to the latest Android Emulator on macOS, you will also have access to the new snapshots UI along with under the hood performance and reliability improvements.

Android Emulator - Snapshots Extended Controls

Microsoft Windows

On Intel x86-based computers, the Android Emulator will continue to use Intel HAXM by default. Intel HAXM is a mature and open-sourced hypervisor solution developed by Intel. Thanks to on-going development by Intel, the fastest emulator performance on Windows is still with Intel HAXM. To download the latest Intel HAXM v7.2.0, check for updates in the Android SDK Manager.

If you have an AMD processor in your computer you need the following setup requirements to be in place:

• AMD Processor - Recommended: AMD^® Ryzen^™ processors
• Android Studio 3.2 Beta or higher - download via Android Studio Preview page
• Android Emulator v27.3.8+ - download via Android Studio SDK Manager
• x86 Android Virtual Device (AVD) - Create AVD
• Windows 10 with April 2018 Update
• Enable via Windows Features: "Windows Hypervisor Platform"

Windows Hypervisor Platform setting in Windows 10

If you want to use Hyper-V at the same time as the Android Emulator on your Intel processor-based computer, you will also need the same Android Studio and Android Emulator versions as listed above, but with the additional requirements:

• Enable via Windows Features: "Hyper-V" - Only available for Windows 10 Professional/Education/Enterprise
• Intel Processor : Intel^® Core^™ processor that supports Virtualization Technology (VT-x), Extended Page Tables (EPT), and Unrestricted Guest (UG) features. Additionally VT-x needs to be enabled in the BIOS.

For more setup tips and troubleshooting details, check out the documentation page.

Again, for existing Windows users who have an Intel-based processor, the Android Emulator will continue to use the faster and recommended Intel HAXM configuration. For those using AMD processors, and those who use Hyper-V hypervisors, this should be an exciting step forward to start using the Android Emulator.

Next Steps & Feedback

Download the latest Android Emulator from the Android Studio 3.2 Beta SDK Manager for the latest performance updates across all supported platforms that you are using. We are going to continue to invest in performance improvements for each of the platforms and we look forward to your feedback and feature requests.

If you find a bug or issue, feel free to file an issue. Connect with us -- the Android Studio development team ‐ on our Google+ page or on Twitter.

09 Jul 2018 5:05pm GMT

Posted by Florina Muntenescu, Developer Advocate & Siyamed Sinir Android Text Technical Lead

In "What's new in Android P Beta" we mentioned two of the new text features in Android.. Now that Android P Beta 2 and the final APIs are here, it's time to dive deeper into what's new for text. We know that TextView is one of the most critical components of the Android view system. This is why we continue to invest in both developer- and user-facing features and API improvements.

PrecomputedText

Displaying text can be complex, encompassing features like multiple fonts, line spacing, letter spacing, text direction, line breaking, hyphenation and more. TextView has to do a lot of work to measure and lay out the given text: reading the font file, finding a glyph, decide the shape, measure the bounding box, and caching the word in an internal word cache. What's more, all of this work takes place on the UI thread, where it could potentially cause your app to drop frames.

We found that measuring text can take up to 90% of the time required to set the text. To solve this problem, in Android P and as part of Jetpack, we introduced a new API: PrecomputedText. This API is available as far back as API 14 via PrecomputedTextCompat.

PrecomputedText enables an app to perform the most time-consuming parts of text layout beforehand, even on a background thread, caching the layout result and returning valuable measurement data. The result of PrecomputedText.create(CharSequence, params) can then be set on a TextView. With this, only about 10% of the work remains to be done by the TextView.

Percentage of time taken to measure and layout text

// UI thread
val params: PrecomputedText.Params = textView.getTextMetricsParams()
val ref = WeakReference(textView)
executor.execute {
    // background thread
    val text = PrecomputedText.create("Hello", params)
    val textView = ref.get()
    textView?.post {
        // UI thread
        val textViewRef = ref.get()
        textViewRef?.text = text
    }
}

Magnifier

Even with features like Smart Text Selection, precisely selecting text can be challenging. Android P introduces the text Magnifier to improve the user experience of selecting text. The magnifier helps users precisely position the cursor or the text selection handles by viewing magnified text through a pane that can be dragged over the text.

Magnifying text in Android P

We wanted users to have the same experience across all apps, whether in custom widgets or during custom text-rendering, so we provided a Magnifier widget that can be applied to any view that is attached to a window. The Magnifier widget can provide a zoomed-in version of any view or surface, not just text.

The Magnifier has 3 main methods: show, update and dismiss. For example, you could call these methods when implementing onTouchEvent-handling for your custom view. This would cause the Magnifier to follow the user's finger along the screen.

fun onTouchEvent(event: MotionEvent): Boolean {
    when (event.actionMasked) {
        MotionEvent.ACTION_DOWN -> 
              magnifier.show(event.x, event.y)
        MotionEvent.ACTION_MOVE -> 
             magnifier.show(event.x, event.y)
        MotionEvent.ACTION_UP -> 
             magnifier.dismiss()
    }
}

Smart Linkify

The Linkify class, which has existed since API 1, allows adding links to text using regexes. On top of that, finding physical addresses spins up a WebView instance to produce the results, which can degrade the performance of the app requesting links. To make link resolution more accurate, especially for internationalized text, and to mitigate the performance degradation caused by the WebView, we created Smart Linkify. Smart Linkify can be accessed using TextClassifier API.

Smart Linkify uses machine-learning algorithms and models to recognize entities in text. This improves the reliability of the entities recognized. Smart Linkify can, based on entity type,suggest actions that the user can perform. For example, if Smart Linkify recognizes a phone number, the API suggests actions such as sending a text message, making a call, or adding to contacts.

Smart Linkify in Android P

To improve the performance of your app, move the work of generating and applying links to a background thread.

// UI thread
val text: Spannable = ...
val request = TextLinks.Request.Builder(text)
val ref = WeakReference(textView)
executor.execute {
    // background thread
    TextClassifier.generateLinks(request).apply(text)
    val textView = ref.get()
    textView?.post {
        // UI thread
        val textViewRef = ref.get()
        textViewRef?.text = text
    }
}

Line Height and Baseline Text Alignment

Designers sometimes provide layout specifications to developers that do not match existing TextView attributes perfectly. On Android P and in Jetpack we added three attributes, together with their corresponding functions, to help bridge this gap between how designers and developers work.

Setting line height

Before Android P, the spacing between lines could be controlled using the lineSpacingExtra and lineSpacingMultiplier attributes. However, designers will commonly provide these values as a simple line height, instead. For this reason, on Android P, we added the lineHeight attribute to set the line height of the text: that is, the distance between the top and bottom of a line (or distance between subsequent baselines). Under the hood, this attribute actually uses and modifies the existing lineSpacingExtra and lineSpacingMultiplier attributes.

Size of line height and font size

<TextView
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:text="Lorem ipsum dolor sit amet"
    app:lineHeight="50sp"/>

// or in code
TextView.setLineHeight(@Px int)

Setting the baseline text alignment

To control the distances of the first and last baselines from the view boundaries, we added two new attributes: firstBaselineToTopHeight and lastBaselineToBottomHeight.

firstBaselineToTopHeight: Sets the distance between the TextView's top boundary and the baseline of the first line of the TextView. Under the hood this attribute updates the top padding.

lastBaselineToBottomHeight: Sets the distance between the TextView's bottom boundary and the baseline of the last line of the TextView. Under the hood, this attribute actually updates the bottom padding.

Distances between first base line to top and last baseline to bottom

<TextView
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:text="Lorem ipsum dolor sit amet"
    app:firstBaselineToTopHeight="28sp"
    app:lastBaselineToBottomHeight="20sp"/>

// or in code
TextView.setFirstBaselineToTopHeight(@Px int)
TextView.setLastBaselineToBottomHeight(@Px int)

Text plays an important role in a vast majority of apps - it's a crucial part of an app's design language. Text is consumed by users, and it even renders emoji 😎. We're continuing to invest in text, improving the experience of both app users and developers.

To learn more about working with text APIs and what's new in Android P for text, check out the Google I/O 2018 talk on "Best practices with text":

04 Jul 2018 3:00pm GMT

Posted by Kacey Fahey, Developer Marketing, Google Play

Join us in congratulating the latest apps and games entering the Android Excellence program on Google Play. This diverse group of apps and games is recognized for their high quality, great user experience, and strong technical performance. Whether you're interested in learning meditation or a new language, or are looking for a game about butterflies or warships, we're excited to dive in to these new collections.

Check out a few of our highlighted apps.

• Beelinguapp: Learn a new language with this unique app. Read and listen to stories with side by side text of the language you're learning, while following along with your language as a reference.
• Fortune City: If you're looking for a fun app to help manage your personal finances, learn how Fortune City teaches good budgeting habits as you build a prospering metropolis.
• ShareTheMeal: Feed a child in need with one tap on your phone, or create a team to fight hunger together with your friends, using this app by the World Food Programme.

Test your skills with these highlighted games.

• Animal Crossing™: Pocket Camp: Take on the role of campsite manager as you collect items to decorate and build your ultimate dream campsite. Meet animals, build friendships and invite your favorite animals over for a fun time.
• Cash, Inc.: Be the big boss of your business empire in this fun game. Work your way up to join a community of business elites and become the most famous money tycoon.
• Shadowgun Legends: Save humanity from an alien invader in an epic Story Campaign spanning over 200+ mission on 4 diverse planets. Along the way, customize your character, team up with friends, and become a celebrity of the Shadowgun Universe.

See the full list of Android Excellence apps and games.

New Android Excellence apps	New Android Excellence games
Beelinguapp BTFIT Fortune City Letras.mus.br LingoDeer Memrise PicsArt Pocket Casts ShareTheMeal The Mindfulness App Tokopedia Trello VivaReal Wynk Music	Animal Crossing™: Pocket Camp Cash, Inc. Flutter: Starlight Shadow Fight 3 Shadowgun Legends War Heroes World of Warships Blitz

Explore other great apps and games in the Editors' Choice section on Google Play and discover best practices to help you build quality apps and games.

How useful did you find this blogpost?

★ ★ ★ ★ ★

03 Jul 2018 5:00pm GMT

From the developer of Meganoid and Stardash comes a new action arcade game: INC! http://www.youtube.com/watch?v=9j5OEG-3RyM Get it from the...

10 Nov 2011 9:31am GMT

More than 1000 broadcast cameras for you online - the most incendiary models in Russia. 1000 girls, 1000, the temptations, 1000, full of desire - all...

10 Nov 2011 7:48am GMT

Hi Friends I decided to work with a tab layout application. Program consist of 3 tabs and a button. I like to place the button below the tab. ...

10 Nov 2011 5:20am GMT

*1-) Spectrum ICS * Image: http://i.imgur.com/IjE5B.jpg *2-) Alien Shapes* Image: http://i.imgur.com/7hQHA.jpg

10 Nov 2011 12:50am GMT

Hey all, New to this site and Android. I'm a 50 year old fireman who has resisted the newest tech gadgets but am wanting a tablet for use at home....

09 Nov 2011 10:33pm GMT

Island Fortress is a free physics based puzzle/construction game where player has to defend the treasure from the pirate's cannonballs....

09 Nov 2011 8:42pm GMT

I have a question about using an unlock code with an HTC T-Mobile MyTouch 3G. So I got the phone from a guy on Craigslist, and I have AT&T. In order...

09 Nov 2011 8:28pm GMT

Free Mini-Bubbles Android Market Link: https://market.android.com/details?id=br.com.dotfive.minibubbles Pop the most bubbles you can within...

09 Nov 2011 6:39pm GMT

Well now a days we are seeing new tablets coming every day and we see new upcoming tablets leaks too! It's difficult to choose best one which works...

09 Nov 2011 4:15pm GMT

Hello, I need unlock code for telephone my touch 3g tmobile. thanks

09 Nov 2011 2:56pm GMT