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Showing posts from November, 2019

Modularizing your Android app, some quick notes (Part 4)

Basically, in part 3 of this series we managed to fully modularize an Android app.  However there are some notes that need to be taken. We didn't cover too much about resources (res folder) in any of our parts therefore we are handling it now.

Here are some things that we should notice about resources in modularization:

1- Strings. No need there for a large file of it. It's easier when each module has access to it's own string values rather than accessing them all from a :core_module. It's easier to read, easier to find strings and if you have a double String resource (like having 2 languages or more) the complexity gets lower. Of course, string resources that are present in more than one module, must remain in the only source of truth.

2- Colors & drawables. It's really important to pay attention to drawables because they significantly affect the APK/Bundle size. The same rule should apply here (not to mention that sometimes we forget to delete drawables that…

Modularizing your Android app, breaking the monolith (Part 3)

On our latest article, what we did was creating a Dagger component about almost all of our features and provided a ViewModel(Factory) for every Fragment we had inside a module. As said, this is a little too much work for Dagger, the programmer and each feature. It's a total overkill of using Dagger actually, we could have stuck to a manual DI instead, but I required you to be patient.

Let me remind you of the current state of the app:

For simplicity I'm not saying in the picture that each component brings a ViewModel(Factory) to the component, please check the previous article if you are confused.

The problem:

I am using a database only in 2 modules, :feature_2 and :feature_4. The rest of the app doesn't care about the database at all. Furthermore, :feature_2 has 0 relations to my :feature_4 entities, while this last one has 2 tables related to each other ( a one to many relationship). But this is not the problem yet. The problem is related to the database being exposed for…

Modularizing your Android app, breaking the monolith (Part 2)

This is part 2 of a series of articles about modularizing Android app. If you haven't yet read the first article, you may find it here.

On our first article we just moved some classes outside the application and applied as an independent module. But what if we have dependencies pulled from the application level? This could be a small challenge. First of all, we want to clarify on how are we going to modularize the app. And depending on the previous article, I chose the by feature version of modularization. First of all, let's show some dependencies that are going to be needed in the whole app.

Note: I'm using Dagger for handling dependencies but manual DI or any dependency tool should be fine to understand this part.

So, this is my dependency schema:

Well, it's not that bad, but this isn't what we want to transform to when trying to modularize the app. If you think about it, modules that don't need a dependency, can get it quite easily. For example: A FeatureXVi…

Modularizing your Android app, breaking the monolith (Part 1)

Inspired by a Martin Fowlers post about Micro Frontends, I decided to break my monolithic app into a modular app. I tried to read a little more about breaking monolithic apps in Android, and as far as I got, I felt confident to share my experience with you. This will be some series of blog posts where we actually try to break a simple app into a modularized Android app.

Note: You should know that I am no expert in this, so if there are false statements or mistakes please feel free to criticize, for the sake of a better development. 

What do you benefit from this approach:
Well, people are moving pretty fast nowadays and delivery is required faster and faster. So, in order to achieve this, modularising Android apps is really necessary.You can share features across different apps. Independent teams and less problems per each.Conditional features update.Quicker debugging and fixing.A feature delay doesn't delay the whole app. As per writing tests, there is not too much difference about…