Not that long ago, I wrote how to pair RxSwift with MVVM architecture in an iOS project. Even if I refactored my code to be reactive, I omitted to mention the unit tests. Today I’ll show step by step how to use RxTest to unit test your code.
For last couple weeks, I’ve worked a lot about how to integrate RxSwift into an iOS project but I wasn’t fully satisfied with the view model. After reading many documentation and trying on my side, I’ve finally found a structure I’m happy with.
It took me quite some time to get into Reactive Programming and its variant adapted for iOS development with RxSwift and RxCocoa. However, being fan of MVVM architecture and using an observer design pattern with it, it was natural for me to revisit my approach and use RxSwift instead. Thats what I’m going to cover in this post.
If you care about user experience, error handling is a big part you have to cover. We can design how an mobile app looks like when it works, but what happen when something goes wrong. Should we display an alert to the user? Can the error stay silent? And mostly how to implement it the best way with your current design pattern? Let’s see our options while following MVVM pattern.
When I started coding years ago, it was all about object oriented programming. With Swift, a new approach came up, making the code even easier to reuse and to test, Protocol-Oriented Programming.
To be sure new code won’t break old one already implemented, it’s best practice to write unit tests. When it comes to app architectures, it can be a challenge to write those tests. Following an MVVM pattern, how to unit test a view and its viewModel? That’s what I would like to cover here using dependency injection.
Creating a new app often raise the question of what architecture to choose, which pattern would fit best. In this post, I show how to implement an MVVM pattern around a sample app in Swift.