Book Image

Simplifying Application Development with Kotlin Multiplatform Mobile

By : Róbert Nagy
Book Image

Simplifying Application Development with Kotlin Multiplatform Mobile

By: Róbert Nagy

Overview of this book

Sharing code between platforms can help developers gain a competitive edge, and Kotlin Multiplatform Mobile (KMM) offers a sensible way to do it. KMM helps mobile teams share code between Android and iOS in a flexible way, leaving room for native development. The book begins by helping you to gain a clear understanding of the Kotlin Multiplatform approach, how it works, and how it is different from cross-platform technologies, such as React Native and Flutter, and code sharing options, such as C++. You'll then see how your team can use this software development kit (SDK) to build native applications more effectively by learning timeless concepts and working through practical examples. As you advance, you'll get to grips with the core concepts, understand why UI sharing fails, and get hands-on with developing a small KMM application. Finally, you'll discover expert tips and best practices, along with production- and adoption-related questions, that will help you take the next step in your project and career. By the end of this Kotlin book, you'll have gained a solid understanding of the capabilities of KMM and be able to share code between Android and iOS flexibly.
Table of Contents (15 chapters)
Section 1 - Getting Started with Multiplatform Mobile Development Using Kotlin
Section 2 - Code Sharing between Android and iOS
Section 3 - Supercharging Yourself for the Next Steps

Testing shared code

Testing shared code in KMP is similar to writing code in KMP: in your shared code, you will have to write platform-agnostic code. This means no third-party testing frameworks or libraries that target a specific platform, JVM, JS, or iOS, such as XCTest or JUnit. Thankfully, KMP already provides a library that targets JVM, JS, and Native:

kotlin.test provides an Asserter abstraction with a DefaultAsserter that is dependency-free, but it also provides JUnitAsserter, JUnit5Asserter, and TestNGAsserter so that you can choose the one you'd like to use in your JVM or Android targets.

You can also implement your own Asserter implementations for the different platforms if you wish. The same expect/actual mechanism can be used in your tests as well.

But what about which test double ( you should choose to test your shared code – Stubs, Mocks, Spies, Fakes, or Dummies...