This is a sandbox with examples of how to setup and solve common issues.

https://github.com/appspell/Scratch/tree/download-in-background

Download file from server using Retrofit with WorkerManager. here

Worker WorkManager Retrofit Permissions

https://github.com/appspell/Scratch/tree/custom_view

Simple CustomView.kt that draws a square at the middle of the view.

CustomView Canvas

https://github.com/appspell/Scratch/tree/db

Add and remove entities using RxJava. here

App adds a new row into a table per each second and observes result using RxJava Flowable in real-time.

RxJava Room Flowable Dagger

https://github.com/appspell/Scratch/tree/mvvm

Request a list of items from a server and show it in the RecyclerView using a simple implementation of DiffUtils. RecyclerView's adapter uses DataBinding.

AndroidX Retrofit Dagger RxJava2 ViewModel LiveData DataBindings