Egor Andreevich - Egor's Blog

Why Trailing Commas In Kotlin Are Hype

Kotlin 1.3.70 landed last week with a bunch of new APIs, bug fixes and tooling improvements (check out the release blog post), but a small change that mostly flew under the radar is this: KT-34743 Support trailing comma in the compilerThe compiler

android

Testing Reactive Presenters: Destructure Your ViewModel Lists!

Back in the early days of Kotlin adoption on Android, many people started writing their unit tests using Kotlin. Even though the primary goal of this approach was to have a possibility to enjoy Kotlin without letting it slip into the actual production code,

kotlin

Inlining Kotlin Properties

Did you know that you can inline properties in Kotlin? I discovered this small feature accidentally while browsing through Kotlin docs, and thought it's worth a short article. So why is this useful? Let's take a trivial Android example: val View.isVisible get() = visibility

kotlin

Preconditions.kt: Validate Your Kotlin

Input validation is important, so you're most likely familiar with the following pattern in Java: public static <T> T getFifthElement(@Nonnull T[] array) { if (array == null || array.length < 5) { throw new IllegalArgumentException( "array should be non-null and have at least

kotlin

Where Should I Keep My Constants in Kotlin?

There has recently been a discussion online about the best approach for storing global constants, or public static final fields in Javaspeak. This short article describes available options and points out some of the pitfalls you can run into. But before we start, let's

android-studio

How to Try the New Android Studio and Get Away with It

It's that time again when the fresh version of Android Studio hits the Canary channel, and of course, you're eager to try it. As soon as you open your project in the new Android Studio, it will nicely ask you to update the Android

android

A Curious Case of Multiple Locales

One of the features introduced in Android N is the possibility to select multiple languages in Settings (Language and Locale), which should enable the system to resolve app locales in a smarter way. Here's how it works. Imagine a person, whose native language is

android

Making Rainbow HAT Work with the Android Things

Google's IoT platform has recently been updated with a couple of exciting new tools: Android Things and Weave. Android Things allows developers to use familiar Android dev tools, such as

kotlin

Concurrency Primitives in Kotlin

I've recently started reading "Android Concurrency" by G. Blake Meike, and so far I can highly recommend this great book: it contains quite a lot of insight into

Understanding Test Rules

If you've ever happened to write Espresso tests, you should be familiar with the following declaration: @Rule public ActivityTestRule<MainActivity> activityRule = new ActivityTestRule<>(MainActivity.class); The addition of @Rules is a relatively new thing in Espresso, historically you would inherit

"Your Espresso, Sir!", or Stepping Up Your UI Tests With Test Butler

Fact #1. Acceptance tests are great. Continuous integration is slowly becoming ubiquitous in mobile app development, and having a Jenkins instance run your entire regression test suite during the night, when everybody on the team is dreaming of sweet Marshmallows and Nougat, or even

android

Providing test doubles with Dagger 1 and Dagger 2

Dagger is a popular dependency injection solution, which works very well with Android, and at the moment is probably a must for any more or less complicated Android project. However, there are things about Dagger that you need to wrap your head around when

Keeping Your Secrets Safe With greenDAO's Database Encryption

One of the most popular Android ORM solutions out there, greenDAO, has recently been updated with a new exciting feature - the database encryption. greenDAO now supports SQLCipher - an open source SQLite extension, that provides transparent 256-bit AES encryption of database files. Data

Taking Photos Not So Simply: How I Got Bitten By ACTION_IMAGE_CAPTURE

I've worked on a number of apps that are taking pictures for different use cases, and since it has always been a secondary feature for those apps, I've relied on using Intents, the approach described in Taking Photos Simply. Intents are powerful, they can

Testing Runtime Permissions: Lessons Learned

Recently I've been working on adding the Android M Runtime Permissions support to the project I'm on at the moment. As an Android user, I find runtime permissions awesome. Permission model was not very user-friendly before Marshmallow: every time you were trying to install

Intro to RxJava/RxAndroid - GDG Munich Android

Yesterday I gave a talk about RxJava and its usage in Android apps at the GDG Munich Android meetup. The code for the demo app and some more RxJava stuff can be found on GitHub, and you can check the slides below. Cheers! Intro

All the things Compat

Android is constantly evolving, every year we get new cool features and new awesome APIs added to the SDK. But backwards compatibility has always been an issue. Here's the Android versions distribution at the time of writing: We're in 2016 already, but KitKat, introduced

Going aspect-oriented with AspectJ and Google Analytics

I've recently stumbled upon an interesting article called Aspect Oriented Programming in Android by Fernando Cejas. I heard about the aspect-oriented programming (AOP) with AspectJ a long time ago and it's always seemed pretty exotic to me, but after I've reviewed the concepts and

android

Reliable functional tests with Espresso and Dagger

One of the core properties of automated tests is that they should be reliable, meaning that a test should either pass or fail, no matter how many times or in what conditions it is being run. Tests that tend to sometimes fail with no

Testing a sorted list with Espresso

Espresso is a pretty powerful tool when it comes to writing acceptance tests for Android. Acceptance tests are the ones that make sure your entire feature (or a certain aspect of the feature) is implemented correctly. The advantage of automating acceptance tests is the

io15

Android M Developer Preview: Running the Fingerprint Dialog sample

So, the Android M Developer Preview is out! All related info is already published, including the Program Overview, guide to Setting up the SDK and the collection of Samples illustrating brand new Android features. One of the hottest Android M features is definitely the

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