Inject view model on activity

[HectorNarvaez]

Added code for perform injection of the view model into the FileViewerActivity

In this PR you will find:

• Added on sample app implementation of activity ktx
• Implementation for provide coroutines scopes
• Implementation of base activity
• Implementation for base view model
• Added abstractions for view event and view state
• Small fix into GoogleStorageApi-
• UI improvements into file viewer activity
• Implement extension function for launch coroutines in a safer way

Evidence:

[Anwera64]

This could be an early return. That would help reduce the indentation levels

[HectorNarvaez]

i think in this particular case, an early return will not reduce indentation levels. It would be something like:

    if(filesAdapter != null) {
        return
    } else {
        filesAdapter = FileGridAdapter(this)
        with(binding.filesRecyclerView) {
            layoutManager = GridLayoutManager(this@FileViewerActivity, 2)
            adapter = filesAdapter
        }
    }

which basically is the same

[Anwera64]

Not really, that's not an early return. It would look something like this:

if (filesAdapter != null) {
    return
}
filesAdapter = FileGridAdapter(this)
with(binding.filesRecyclerView) {
    layoutManager = GridLayoutManager(this@FileViewerActivity, 2)
    adapter = filesAdapter
}

[HectorNarvaez]

i think in general use inverse logic in a conditional makes code less readable than just do a straight comparison.
Anyway, i applied the suggested change 😃

done ✅

[Anwera64]

I disagree. Early returns serve as precondition checks that show you what would stope the code from running in the first place. If you would have multiple validations, they would all go first and show you all the failure cases for the function.

[HectorNarvaez]

yeah, i'm ok with early returns. I mean about use inverse logic. I think is more readable use if(boolean) instead if(!boolean)

[Anwera64]

LGTM