Understand Kotlin Coroutines on Android (Google I/O'19)
Coroutines are a feature of Kotlin that help convert callback-based code into sequential code, making code easier to read, write, and understand. This session will show you how to use coroutines on Android, and how the new androidx-concurrent library makes it easy to use them to get things off the main thread. You'll also learn how the new library helps coroutines work with Architecture Components
Locale changes and the AndroidViewModel antipattern
TL;DR: Expose resource IDs from ViewModels to avoid showing obsolete data. In a ViewModel, if you’re exposing data coming from resources (strings, drawables, colors…), you have to take into account that ViewModel objects ignore configuration changes such as locale changes. When the user changes their locale, activities are recreated but the ViewModel objects are not. The localized string is not up
Android Data Binding Library — From Observable Fields to LiveData in two steps
One of the most important features of Data Binding is observability. It allows you to bind data and UI elements so that when the data changes, the pertinent elements are updated on screen. Plain primitives and Strings are not observable by default so if you use them in your Data Binding layouts, their values will be used when the binding is created but subsequent changes to them will be ignored. T
Room コルーチン
.app 1 .dev 1 #11WeeksOfAndroid 13 #11WeeksOfAndroid Android TV 1 #Android11 3 #DevFest16 1 #DevFest17 1 #DevFest18 1 #DevFest19 1 #DevFest20 1 #DevFest21 1 #DevFest22 1 #hack4jp 3 11 weeks of Android 2 A MESSAGE FROM OUR CEO 1 A/B Testing 1 A4A 4 Accelerator 6 Accessibility 1 accuracy 1 Actions on Google 16 Activation Atlas 1 address validation API 1 Addy Osmani 1 ADK 2 AdMob 32 Ads 71 Ads API 11
Room 🔗 Coroutines
Room 2.1 adds support for Kotlin coroutines. DAO methods can now be marked as suspending to ensure that they are not executed on the main thread. Read on to see how to use this, how it works under the hood and how to test this new functionality. Add some suspense to your databaseTo use coroutines and Room in your app, update to Room 2.1 and add the new dependency to your build.gradle file: impleme
AACのViewModelをFactoryクラス不要で簡単に生成できる拡張関数 - Qiita
Androidで、MVVM及びdatabindingを行う場合、Android Architecture ComponentsのViewModelを使うことが多いと思います。 このViewModelを生成する際、コンストラクタに引数が必要だとFactoryクラスを作成する必要がありますが、ViewModelが多くなってくるとその分Factoryも増えていき、作成・管理が面倒になったので拡張関数を作成しました。 結論 忙しい人のために先に結論 Fragment.getViewModelと Fragment.viewModelProviderを作りました。 使い方 class SampleFragment: Fragment(), SampleNavigator { // フィールドでvalで持ちたい場合は、viewModelProvider private val viewModel by
7 Pro-tips for Room – Android Developers – Medium
Room is an abstraction layer on top of SQLite that makes it easier and nicer to persist data. If you’re new to Room then check out this primer: In this article, I’d like to share some pro-tips on getting the most out of Room: Pre-populate your database via RoomDatabase#CallbackUse DAO’s inheritance capabilityExecute queries in transactions with minimal boilerplate code via @TransactionRead only wh
LiveData&CoroutinesのUnitテスト | DevelopersIO
Env Kotlin 1.3.0-rc-57 kotlinx.coroutines 0.26.1-eap13 Architecture Components 1.1.1 Mockito-Kotlin 2.0.0-RC2 TL;DR Architecture Components用のテストライブラリを導入する testImplementation "android.arch.core:core-testing:1.1.1" テストルールを書く @get:Rule val rule: TestRule = InstantTaskExecutorRule() コルーチンの実行スレッドを切り替える Dispatchers.Unconfined or runBlocking {} Test target 今回は、購入履歴をAPIから取ってきて、ViewModelに渡して、DataBindingを使っ
Android's Architecture Components
In 2017, Google introduced the Architecture Components library, with Google-supplied implementations of object-relational mapping (ORM) capabilities and lifecycle-aware components. This book dives deep into the Architecture Components, showing you how they work individually and in concert. With dozens of sample projects, the book covers much of what blog posts miss, in terms of how to make this li
5 common mistakes when using Architecture Components
Lunch Atop a Skyscraper by BalakovSubtle oversights with more or less serious consequences - even if you’re not making these mistakes it should be worth keeping them in mind to avoid running into some problems in future. This article covers: Leaking LiveData observers in FragmentsReloading data after every rotationLeaking ViewModelsExposing LiveData as mutable to ViewsCreating ViewModel’s dependen
Android Room with a View - Kotlin
Android Room with a View - Kotlin Stay organized with collections Save and categorize content based on your preferences. 1. Before you begin The Android Architecture Components collection provides guidance on app architecture, with libraries for common tasks like lifecycle management and data persistence. Using architecture components can help you structure your app in a way that is robust, testab
Android ViewModelのフィールドをView側で購読するときの工夫 - ブログに書くことがない
Androidで1年くらいViewModelを書いてきてつらいなと思ったことと、それを解決するための工夫を軽くまとめました。 AndroidでViewModelを書くとき、こんな感じにして、 class ProfileViewModel : ViewModel() { private val nameSubject: BehaviorSubject<String> = BehaviorSubject.create() val name = nameSubject.hide()!! ... } こういう感じでView側で購読することが多いと思うが、 class ProfileFragment : Fragment() { ... private fun setup() { profileViewModel.name .observeOn(AndroidSchedulers.mainThrea
Android Paging Library — Make your lists as efficient as possible literally in just an hour…
So, the new Paging Library is coming to Android as a part of the Architecture Components. It’s still in alpha but there is no doubt that you are already ready to try it! And I’m not gonna tell you about the usage of all this stuff. Because this article it’s just a short addition of the great article by Chris Craik that you are able to read here. So, when you should use it. Ok, if you gradually loa
新しく追加されたAACのLifecycleObserverを使ってAndroidのライフサイクルのコードをスッキリさせよう！ - Qiita
典型的なオブザーバーパターンですね（ええ、たぶん）。 きっとLifecycle側がMyLifecycleObserverに各ライフサイクルイベントで通知してくれるんでしょうねー。 わかりやすいインターフェイスデザインで助かります。 何をスッキリさせたいか これについて多分割とたくさんの人に動機があると思うんですが、ActivityやFragmentのライフサイクルのコールバックって見づらいですよね。 僕個人は特にonStart()/onCreate()とonStop()/onDestroy()をコード上になるべく近くに配置したいです。保守性って意味で。 でも簡単に割とバラバラになるし、ほかのメソッドと合わせて順番なんてその時の事情で様々です。 BroadcastReceiverなんかは僕が一番嫌いなコードになりやすいです。メンバー変数定義して、その変数の複数のコールバックで必要になり。 こ
Android Architecture Componentsを使ってリファクタリングした話
shibuya.apk#26
Room InvalidationTracker potatotips #52
class: chapter-1, hero, center, middle # <nobr>Room のできるまで</nobr> ## 〜 InvalidationTracker 編 〜 potatotips #52 2018/06/21 荒木佑一 --- class: chapter-1, normal # 自己紹介 .card[ 荒木佑一<br> @yuichi_araki Google Developer Relations<br> Developer Programs Engineer - AndroidX (Transition, Room) - developer.android.com や GitHub のサンプルコード - Android Studio のテンプレート - Google I/O アプリ、サンタ トラッカー ] --- class: chapter-2, n
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Livedata beyond ViewModels: A stateful approach for UI
Yuichi Arakiさんのツイート: "もうどこかにありそうだけど、 SharedPreferences を LiveData として監視できるの作った。 https://t.co/FJKpvGFg6K"
GitHub - Shopify/livedata-ktx: Kotlin extension for LiveData, chaining like RxJava
Firebase & Jetpack: fit like a glove (360|AnDev, Denver)