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

Tying the iOS app together with the shared code

If you try to subscribe to the breeds stream from the BreedsRepository repository, you'll see that you can't really initialize this repository from the iOS code. This is because we've made a mistake—we don't really want to deal with Koin from Swift, so we could just migrate to a similar injection pattern that we've used for the use cases, as illustrated in the following code snippet:

class BreedsRepository: KoinComponent {
    private val remoteSource: BreedsRemoteSource by
    private val localSource: BreedsLocalSource by inject()

Now, if you try to call some of our use cases, you can see that you can call suspend functions, as illustrated in the following screenshot, and you'll get back a CompletionHandler, since Kotlin 1.4:

Figure 7.3 – Calling suspend functions from Swift

Now, there...