getoxdev / MVVM_DEMO

MVVM demo with Retrofit 2, RxJava 2 and SharedPreference

This project shows the basic structure of the MVVM architecture.

Google developers doc : https://developer.android.com/jetpack/docs/guide . https://proandroiddev.com/mvvm-architecture-viewmodel-and-livedata-part-1-604f50cda1 you can check out other blogs too.

Project Structure

1. Data :
   • Api : All API related stuffs are done here.
     • ApiHelper Interface : Helper interface for api calls
     • ApiService Interface : Interface declaring all the methods for the api call
     • AppApiHelper class : It implements ApiHelper . This is the api provider for Data manager class. Retrofit is initialized here.
   • Models :
     • UserResponse class: Response class for the network call.
   • Prefs :
     • PreferencesHelper Interface : class implementing the PreferencesHelper. Shared Preferences is initialized here.
     • AppPreferencesHelper class : interface for shared Preferences.
   • AppDataManager : DataManager class for the app . It combines the api service and the shared preferences.
   • DataManagerHelper : Datamanager interface.
2. Retrofit -RetrofitClient : Retrofit is declared here.
3. Ui-main: -Adapter: RecyclerViewAdapter -MainActivity : Single activity of the app.
4. ViewModel : It is the class where all the business logic of the app is done.

Libraries used :

• Butterknife : Android ButterKnife library is a view injection library that injects views into android activity / fragments using annotations. For example, @BindView annotation avoids using findViewById() method by automatically type casting the view element. https://github.com/JakeWharton/butterknife
• ViewModel : The ViewModel class is designed to store and manage UI-related data in a lifecycle conscious way. The ViewModel class allows data to survive configuration changes such as screen rotations. Check out https://developer.android.com/topic/libraries/architecture/viewmodel
• Retrofit 2 : Retrofit is a REST Client for Java and Android. It makes it relatively easy to retrieve and upload JSON (or other structured data) via a REST based webservice. For more info check out https://square.github.io/retrofit/
• RxJava 2 : RxJava is a library that lets you create applications in the reactive programming style. At its core, reactive programming provides a clean, efficient way of processing and reacting to streams of real-time data, including data with dynamic values. You don't need to deep dive into rxjava 2 . You can explore basic Rxjava by following this link https://code.tutsplus.com/tutorials/getting-started-with-rxjava-20-for-android--cms-28345
• Shared Preferences : If you have a relatively small collection of key-values that you'd like to save, you should use the SharedPreferences APIs. A SharedPreferences object points to a file containing key-value pairs and provides simple methods to read and write them. Each SharedPreferences file is managed by the framework and can be private or shared. Check out https://developer.android.com/training/data-storage/shared-preferences