An Android experiment using MVVM and DataBinding.
I used Kotlin instead of Java, which it's pretty much self explanatory.
The architecture that I'm using it's a simple MVVM with DataBinding without the Architecture Components.
I wanted to use DataBinding pointing directly to the ViewModel fields, which is only possible using MutableLiveData after the 3.1.0-alpha Gradle release.
I'm not very confident with the alpha version to use it in this experiment, that's why I used ObservableField instead.
The dependency graph is built based on dagger.android.
I created three types of scope to include all dependencies.
- Singleton for app level dependencies
- ActivityScope for every dependency used inside an Activity lifecycle
- FragmentScope dependencies living inside a Fragment attachment lifecycle
All the communication between Activity <-> Fragments are done via DI using scopes.
I used the APIs from Google Play Services, like the Current Place Discovery and Predictions.
For location updates I used the new FusedLocationProviderClient implementation.
I created a simple logic for the place discovery, if the Google Places returns an address more than 30 meters away from the current user position, I fetch the local Geocoder for closer current address.
Yeah I used mostly Fragments to do the View layer, but please don't be scared.
The reasons that I chose to use Fragments were:
- I wanted to create smooth transitions between Views
- Load the Map just once (performance stuff)
- With Fragments it was much more simpler to create Subcomponent scopes using DaggerAndroid.
- Update Gradle to 3.1.0-alphaX to use
MutableLiveDatainstead ofObservableFieldfor DataBinding
I won't discuss everything in this file, but if you have any question or want to kill me for anything that I did, please contact me I'll be glad to discuss it with you.