Posted by Wojtek Kaliciński, Developer Advocate, Android
Stephanie Saad Cuthbertson announces support for Kotlin during the Developer Keynote at I/O 2017.
Today at OSCON (the O'Reilly Open Source Software Conference), Kotlin was awarded the Open Source Award for Breakout Project of the Year.
There is no doubt to us why Kotlin received this award: it’s a fast moving (but thoughtfully developed) programming language that lets you write better code, faster. It’s great to see Kotlin continue to receive the sort of recognition as Breakout Project of the Year, building on other awards like #1 fastest growing language on Github.
We’re big fans of Kotlin, and we’ve heard that you are too – feedback from you is in part why we announced support for the language over two years ago. This meant bundling the Kotlin plugin in Android Studio, along with promising to support Kotlin-built apps going forward.
But there was a long way to go for many teams at Google to provide a first class experience with Kotlin in the Android ecosystem, and to convince developers that Kotlin on Android is not just a fad, but is here to stay.
If you haven’t tried Kotlin yet, now is a great time to start! In fact, in the past two years, we’ve been adding a number of new features and upgrades to the Kotlin for Android experience, including:
The road to fully supporting Kotlin on Android was not always easy, but it was truly rewarding seeing Kotlin adoption among professional Android developers rise from a handful of early adopters to around 50% since the original announcement!
We were confident when we announced earlier this year at Google I/O 2019 that Android is going increasingly Kotlin-first, opening up the possibility for APIs built specifically around Kotlin and for Kotlin users, starting with the new, declarative UI toolkit - Jetpack Compose (still in early development).
We want to congratulate JetBrains, our partners through the Kotlin Foundation and creators of Kotlin, on receiving the OSCON Open Source Award today. It shows how disruptive and transformative Kotlin has been, and not just for the Android developer community, but beyond.
We know one thing: on Android, Kotlin is here to stay.
Posted by Sean McQuillan, Developer Advocate, Android
Registration is now open for Android Dev Summit 2019!
Learn, share, and connect at #AndroidDevSummit 2019. It's a great place to learn new Android development skills, share feedback and ideas with the Android engineering team, and connect with Android developers from around the globe.
Join us for the two day conference on October 23-24 hosted at the Google Event Center (MP7) in Sunnyvale, CA. We'll share two days of deep technical talks covering topics such as Jetpack, Android Studio, Android Q, Kotlin, and more. You will learn about the latest innovations straight from the Android engineering team, discover best practices to help you build even better apps, and accelerate your teams’ productivity on Android.
The Android engineering team will be there in person to answer your questions, hear your ideas and feedback (we love that!), and discuss the direction of Android development. And you will be joined by Android developers from around the globe — it’s a great place to connect with your community.
Conference details
When: October 23-24
Where: Google Event Center (MP7)
Unable to attend?
Wherever you are, you can still watch the talks and engage with the community. You can tune in from anywhere to watch all of the talks online by joining our livestream. Sign up here to stay updated on event announcements. All of the talks will also be posted on YouTube soon after the event, so you can always catch up with the recordings on your own schedule.
The event schedule has not yet been posted, but we encourage you to check out last year’s sessions to learn more about the great content and opportunities Android Dev Summit has to offer.
Register now
Attendance is free and by invitation only — register now to become eligible for an invitation. Selected attendees will receive their tickets after registration closes on August 15th at 5:00pm PDT. #AndroidDevSummit will fill up fast, so be sure to register today.
Posted by Florina Muntenescu, Android Developer Advocate
Displaying text is an important task in most apps, so in Android Q we're continuing to introduce new features to support your needs and improve performance. We disabled hyphenation by default, enabled creating a typeface using multiple fonts or font families, exposed the list of fonts installed on the device, and improved some of the most-used text styling APIs.
Our performance tests showed that when hyphenation is enabled, up to 70% of the time spent on measuring text is on hyphenation.
Hyphenation takes up to 70% of the time spent measuring text
Given that hyphenation often isn’t needed for all TextViews in an app, and because of the impact on performance, we decided to turn hyphenation off by default in Android Q and AppCompat v1.1.0. If you want to use hyphenation, you need to manually turn it on in your app by setting the hyphenation frequency to normal. You can set this in multiple ways:
TextViews
As a TextAppearance attribute in styles.xml:
TextAppearance
styles.xml
<style name="MyTextAppearance" parent="TextAppearance.AppCompat"> <item name="android:hyphenationFrequency">normal</item> </style>
As a TextView attribute:
TextView
<TextView android:hyphenationFrequency="normal" />
Directly in code:
textView.hyphenationFrequency = Layout.HYPHENATION_FREQUENCY_NORMAL
Find out more about how hyphenation works from this talk at Android Dev Summit 2018.
Consider a button which mixes a custom font (Lato in this example) with an icon font:
Button with icon and Latin fonts
The Button class accepts only a single instance of a typeface to be set on the text. Pre-Android Q, you can create a Typeface using a single font family. Android Q enables the creation of a typeface from multiple font families with a new API, Typeface.CustomFallbackBuilder, that allows adding up to 64 font families per typeface.
Button
Typeface
Typeface.CustomFallbackBuilder
Our icon font example can be implemented like this:
button.typeface = Typeface.CustomFallbackBuilder( // add the Latin font FontFamily.Builder( Font.Builder(assets, "lato.ttf").build() ).build() ).addCustomFallback( // add the icon font FontFamily.Builder( Font.Builder(assets, "icon_font.ttf").build() ).build() ).build()
When creating the font family, make sure you don’t put fonts that belong to different families in the same font family object nor the same style fonts into the same font family. For example, putting Lato, Kosugi, and Material into the same font family creates an invalid configuration, as does putting two bold fonts into the same font family.
To define the general font family (serif, sans-serif, or monospace) to be used when text is rendered using system fonts, use the setSystemFallback() method to set the system fallback font:
setSystemFallback()
Typeface.CustomFallbackBuilder( FontFamily.Builder( ... ).build() ).setSystemFallback("sans-serif") .build()
Android Q brings several updates to different text styling APIs:
TextAppearance now supports the fontVariationSettings attribute:
fontVariationSettings
<style name="MyTextAppearance" parent="TextAppearance.AppCompat"> <item name="android:fontVariationSettings">...</item> </style>
The fontVariationSettings attribute can be set directly on the TextView in Android Q and in AppCompatTextView:
AppCompatTextView
<TextView ... app:fontVariationSettings="..." />
TextAppearanceSpan now supports typeface, shadow settings, fontFeatureSettings and fontVariationSettings.
TextAppearanceSpan
typeface
fontFeatureSettings
LineBackgroundSpan and LineHeightSpan interfaces now have standard implementations: LineBackgroundSpan.Standard and LineHeightSpan.Standard.
LineBackgroundSpan
LineHeightSpan
LineBackgroundSpan.Standard
LineHeightSpan.Standard
With more than 100 languages supported by Android, and with different fonts supporting different character sets, knowing which system font can render a given character is not trivial. Apps doing their own text rendering such as games, document viewers, or browsers need this information. In Android Q, you can retrieve the supported system font for a string with the FontMatcher NDK API.
FontMatcher
System fonts that can render this text
Let’s consider the above search string. The FontMatcher API returns us the font object and length. A simplified pseudocode example looks like this:
// font = NotoSansCJK-Regular.ttc // length = 2 auto[font, length] = AFontMatcher_match("たすく a.k.a. のな"); // font = Roboto-Regular.ttf // length = 8 auto[font, length] = AFontMatcher_match(" a.k.a. のな"); // font = NotoSansCJK-Regular.ttc // length = 2 auto[font, length] = AFontMatcher_match("のな");
The FontMatcher API never returns nullptr:
nullptr
If you want to get all available system fonts, you can do this with a new font enumeration API. In Java, you can use SystemFonts.getAvailableFonts, or in the NDK, you can use ASystemFontIterator. The results of the font enumeration are changed only by a system update, so you should cache them.
SystemFonts.getAvailableFonts
ASystemFontIterator
Android added a new Myanmar font to Android Q that is Unicode-compliant and capable of rendering both Unicode and non-Unicode Burmese (commonly known as Zawgyi), right out of the box. This means starting in Android Q, Android makes it easier for users to switch to Unicode: a user can now use a Unicode font to read Unicode and non-Unicode text for the first time. Android also added new requirements to the Android ecosystem CDD that takes a stronger stance in requiring Unicode, including a new subtag "Qaag" which OEMs should use as a locale designating non-Unicode Burmese. All of these changes should make developers’ life easier in the long term, as reduced ecosystem fragmentation makes it easier to develop for our 50M users in Myanmar.
Emojis in Android Q
Say Hello to your new emoji friends! The latest update includes a number of disability-focused emojis, multi-racial couples, as well as a few cute animals and household objects. See the latest and greatest in Gboard on your Android Q device of choice.
Text plays an important role in a vast majority of apps, so we’re continuing to invest in improving text API features and performance. Learn more about the new APIs in Android Q along with best practices when working with text in our Google I/O 2019 talk:
Posted by Dave Burke, VP of Engineering
Android Q Beta 5 launches today! Today we're rolling out Beta 5, bringing Android Q Beta very close to the system behaviors you'll see in the final release. Developer APIs were already finalized in the previous update. So, now is the time to test your apps for compatibility and make sure they are ready!
You can get Beta 5 today on Pixel devices by enrolling here. If you're already enrolled and received Beta 4 on your Pixel device, you'll automatically get the update to Beta 5. Partners participating in the Android Q Beta program will also be updating their devices to Beta 5 over the coming weeks.
To get started with Android Q Beta, visit developer.android.com/preview.
The Beta 5 update includes the latest Android Q system images for Pixel and Android jEmulator, along with the final Android Q developer APIs (API level 29), the official API 29 SDK, and updated build tools for Android Studio. These give you everything you need to test your apps on Android Q and build with Android Q features.
As we talked about at Google I/O, we’ve been working closely with device-maker partners to ensure a standardized Android gestural navigation for users and developers. Gestural navigation lets apps use the full screen for content while minimizing the visible system chrome and navigation – which is particularly important on today’s edge-to-edge screens. In Beta 5 we’re continuing to improve and polish based on your feedback and we wanted to provide an update on a few key areas.
We’ve introduced a swipe gesture from either corner to get to the Assistant - you’ll notice indicators in the bottom corners that we’re continuing to tune.
For apps using a navigation drawer, we’ve added a peek behavior when users have grabbed the drawer to indicate that a swipe will bring in the navigation drawer. This works for all versions of DrawerLayout, with DrawerLayout 1.1.0-alpha02 optimized for the best experience.
Custom launchers are another area where we’ve heard feedback and we’re continuing to work on issues, particularly with stability and Recents. Starting in Beta 6, we’ll switch users to 3-button navigation when they are using a custom launcher by default. We’ll address the remaining issues in a post-launch update allowing all users to switch to gestural navigation. Meanwhile, please continue to give us your feedback.
With the consumer release coming soon, it’s highest priority for all Android developers to update your current apps for compatibility as soon as possible.
Here’s how to do it:
We realize that supporting these changes is an investment for you too, and we're working to minimize the impact on your apps and be responsive to your input as we move toward the final release.
Next, when you're ready, dive into Android Q and learn about the new features and APIs that you can use. Here are some of the top features to get started with.
We recommend these for every app:
We recommend these if relevant for your app:
These are just a few of the many new features and APIs in Android Q -- to see them all, visit the Android Q Beta site for developers.
As soon as you're ready, publish your APK updates to Google Play that are compiled against, or optionally targeting, API 29. To make sure that your updated app runs well on Android Q as well as older versions, try using Google Play testing tracks. With tracks you can safely get early feedback from a small group of users -- including Beta 5 users — and then do a staged rollout to production.
It’s easy! Just enroll any supported Pixel device here to get the update over-the-air. If you're already enrolled, you'll receive the update soon and no action is needed on your part. Downloadable system images are also available here. Partners who are participating in the Android Q Beta program will be updating their devices over the coming weeks. See android.com/beta for details.
To get started developing, download the official API 29 SDK and tools into the stable release of Android Studio 3.4, or for the latest Android Q support update to Android Studio 3.5 Beta. Then follow these instructions to configure your environment, and see the release notes for known issues.
There will be one more Beta release before the consumer launch later this quarter. Please continue to share your feedback and requests -- you can use our hotlists for filing platform issues (including privacy and behavior changes), app compatibility issues, and third-party SDK issues.
Also, the Android engineering team will host a Reddit AMA on r/androiddev to answer your technical questions about Android Q later this month. Look out for an announcement on r/androiddev with details in the coming weeks. We look forward to addressing your questions!
Posted by Don Turner, Developer Advocate for Android Media
In Android Q there's a new API which allows applications to capture the audio of other applications. It's called the AudioPlaybackCapture API and it enables some important use cases for easier content sharing and accessibility.
Some examples include:
There may be some situations where a developer wishes to disallow the capture of their app's audio. This article explains how audio capture works for users and how developers can disallow their app's audio from being captured if they need to.
In order to capture the audio of other apps the user must grant the record audio permission to the app doing the capturing.
AUDIO_RECORD permissions dialog
Additionally, before a capture session can be started the capturing app must call MediaProjectionManager.createScreenCaptureIntent(). This will display the following dialog to the user:
MediaProjectionManager.createScreenCaptureIntent()
Screen capture intent dialog
The user must tap "Start now" in order for a capturing session to be started. This will allow both video and audio to be captured.
Cast icon showing red in status bar
During a capture session the cast icon is shown in red in the status bar.
Whether your app's audio can be captured by default depends on your target API. Here's a table which summarizes the default behaviour:
There may be situations where an app wishes to disallow its audio from being captured by other apps. This could be because the audio contains:
An app's audio capturing policy can be set either for all audio or for each individual audio player.
To disallow capture of all audio by third party apps you can do either of the following:
AndroidManifest.xml
<application
...
android:allowAudioPlaybackCapture="false"/>
AudioManager.setAllowedCapturePolicy(ALLOW_CAPTURE_BY_SYSTEM)
To disallow capture for an individual player you can set the capture policy for the audio player when it is built by calling:
AudioAttributes.Builder.setAllowedCapturePolicy(ALLOW_CAPTURE_BY_SYSTEM)
This approach may be useful if your app plays content with differing licenses. For example, both copyrighted and royalty-free content.
By default system apps and components are allowed to capture an app's audio if its usage is MEDIA, GAME and UNKNOWN, as this enables important accessibility use cases, such as live captioning.
In rare cases where a developer wishes to disallow audio capture for system apps as well they can do so in a similar way to the approach for third party apps. Note that this will also disallow capture by third party apps.
This can only be done programmatically by running the following code before any audio is played:
AudioManager.setAllowedCapturePolicy(ALLOW_CAPTURE_BY_NONE)
To disallow capture for an individual player you can set the capture policy for the audio player when it is built:
AudioAttributes.Builder.setAllowedCapturePolicy(ALLOW_CAPTURE_BY_NONE)
If your app is targeting API 28 or below and you would like to enable audio capture add android:allowAudioPlaybackCapture="true" to your app's manifest.xml.
android:allowAudioPlaybackCapture="true"
manifest.xml
If you would like to disallow some or all of your audio from being captured then update your app according to the instructions above.
For more information check out the Audio Playback Capture API documentation.
Posted by Patricia Correa, Director, Developer Marketing
We just wrapped up the Indie Games Showcase in Europe, Japan & South Korea! Back in March we started our search for some of the newest and most creative indie titles from these regions. The search culminated last week with the celebration of indie developers at events in London, Tokyo, and Seoul, and the selection of the winners from our finalists. Developers from 12 countries traveled to the events and showcased their games to the audience of gamers, industry experts, YouTube creators, and journalists.
The games were on show to the public, who spent several hours trying out their games and voting for their favourites, alongside the Google Play team. The top 10 finalists were then selected, and went on to pitch their games, and compete for big prizes in front of the jury.
Now, we are happy to announce the winners from each region! They will be returning home with a prize package that includes promotions on the Google Play Store, consultations with Google teams, Google hardware, and more.
We also want to take this opportunity to congratulate all the other finalists and developers who entered the competition this year. We are impressed by your creativity and passion, and hope you will continue to create amazing experiences for players worldwide.
G30 - A Memory Maze by Ivan Kovalov (Russia)
Ordia by Loju (United Kingdom)
Photographs by EightyEight Games (United Kingdom)
The other finalists as selected by audience and Google Play votes were:
#DRIVE by Pixel Perfect Dude (Poland)
Fly THIS! By Northplay (Denmark)
Golf Peaks by Afterburn (Poland)
Rest in Pieces by Itatake (Sweden)
see/saw by Kamibox (Germany)
STAP by Overhead Game Studio (United Kingdom)
Tesla vs. Lovecraft by 10tons (Finland)
Infection - 感染 - by CanvasSoft
MeltLand by 個人
Bear's Restaurant by 個人
Lunch Time Fish by SoftFunk HULABREAKS
ReversEstory by 個人
Kamiori - カミオリ by TeamOrigami
キグルミキノコ Q-bit -第一章- by 個人
クマムシさん惑星 ミクロの地球最強伝説 by Ars Edutainment
Girl x Sun - Terasene - Tower defence & Novel game by SleepingMuseum
Persephone by Momo-pi
ROOMS: The Toymaker's Mansion by HandMade Game
Seoul2033: Backer by Banjiha Games
Cartoon Craft by Studio NAP
Hexonia by Togglegear
Hexagon Dungeon by Bleor Games
7Days - Decide your story by Buff Studio
WhamBam Warriors by DrukHigh
Onslot Car by Wondersquad
Maze Cube by IAMABOY
언노운 나이츠 by teamarex
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Posted by Oscar Rodriguez, Developer Advocate
When designing and developing an app or game, at some point you may ask yourself if you want to monetize it.
If you choose to do so by selling products via Google Play, you will most likely have a store screen that shows available items for sale, and use the Google Play Billing Library to display dialogs that allow your users to complete their purchase.
While there is a more detailed explanation in the documentation and in the Billing Library TrivialDrive samples, the general flow is as follows:
launchBillingFlow()
onPurchasesUpdated()
consumeAsync()
acknowledgePurchase()
If your app is still using the Google Play Billing AIDL API, it is also possible to perform the same task. Keep in mind that the AIDL API is now deprecated, so we strongly recommend you migrate to the Google Play Billing Library as soon as possible.
If you are using the AIDL API, the flow is very similar:
getBuyIntent()
getBuyIntentExtraParams()
startIntentSenderForResult()
Intent
onActivityResult()
getPurchases()
consumePurchase()
Nevertheless, just implementing the above mentioned flow is not enough to correctly handle all types of purchases. There are two main cases in which purchases will not be correctly handled by this flow.
The first case happens when the purchase flow is interrupted before it finishes. The app may have crashed, the user may have killed the app, or the user’s Internet connection may have been lost. In any case, it is possible for the app not to have delivered the item to the user even though Google Play has already processed the payment. In this case, the item is in limbo, because Google Play will not allow an item to be re-purchased until it is consumed, but the app or game won’t consume the item outside of the flow mentioned above.
The second case happens during alternative purchase flows, such as in-app promotions, the recently announced out-of-app subscription surfaces, promo codes for subscriptions, or other promotions in collaboration with Google. In these cases, a user gets an item directly on the Play Store app, while the target app or game may be paused, not running, or even not installed.
For these cases, the Google Play Billing Library and the Google Play Billing AIDL API offer a mechanism to detect purchases that are not acknowledged or consumed.
When using the Google Play Billing API, do the following:
onResume()
queryPurchases()
For the Google Play Billing AIDL API, do the following:
In either case, when you detect and process an unconsumed item in this manner, users will expect the app or game to communicate about it. We suggest that you display a dialog, message box, or notification that tells the user that they have successfully received their item.
Keep in mind that your app’s onResume() callback will be called when its process is started, as well as when it is brought to the foreground, regardless of which screen the app or game was in before it was paused. For example, a game with a home screen, a store screen, and a game screen might get its onResume() called from any of those screens. For an optimal user experience, we suggest you make it so your app or game handles unacknowledged or unconsumed items regardless of the screen you display when onResume() gets called. Thorough testing of this process in each screen is crucial to deliver a great user experience.
Finally, there is one more case your app must handle: when a user acquires an item from the Play Store app, and both the Play Store app and your app are visible at the same time with multi-window mode.
To support this scenario with the Google Play Billing Library, do the following:
PurchasesUpdatedListener
com.android.vending.billing.
PURCHASES_UPDATED
onPause()
Just as before, you should display a dialog, message box, or notification that tells the user that they have successfully received their item.
If you follow these steps, your app or game will be better prepared to robustly handle purchase flow interruptions and alternative purchase flows.
