islamarr / recorder

Simple Recorder Application

Recorder

About this project:

1- Kotlin
2- MVVM
3- LiveData
4- ViewModel
5- Hilt DI
6- Repository pattern
7- Navigation component
8- Data Binding
9- Room DB
10- Coroutines
11- Unit testing (local tests + instrumented tests)

Technical choices

RecyclerView vs Listview

• In RecyclerView, it is mandatory to use ViewHolder pattern Which optimize the performance.
• DiffUtil callback Which optimize the performance.
• There is no official way to implement a horizontal ListView. But in RecyclerView by using Layout Manager you can do vertical, Staggered or Gridlayout

Activities vs Fragments

• I have used a single-activity architecture which allowed me to take full advantage of the Navigation component, which mean that a single activity that manages and host multiple fragments.
• The fragment is more lite weight than Activity.

ViewModel vs AndroidViewModel

AndroidViewModel is a Application context aware ViewModel. As I didn't need to use context inside my ViewModel classes, I've used ViewModel.

Unit test vs instrumented test

In cases where I wanted to test the behavior of some screens in a real device I used instrumented test by Espresso and Mockito. In the functions I didn't need a physical device I used the local Unit Tests.

Hilt vs Dagger2 vs Koin

• Hilt does not need factories for ViewModel , Dagger need
• Hilt generate the code in the compile time , koin runtime generation code