android - RecyclerView with RoomDatabase an ViewModel

Question

I'm showing my recycler view like this:

   parrafoLeyViewModel.allParrafosLey.observe(this, Observer {  

    recyclerview_lectura_ley.layoutManager = LinearLayoutManager(this)
    adapterListar = AdapterListarLey(this, it, this)
    recyclerview_lectura_ley.adapter = adapterListar

   })

So when I insert data into the RoomDatabase my recyclerview restarts and goes back to the start

    GlobalScope.launch {
                    db.parrafoLeyDao().updateComentarioLey(
                        ComentarioLey(
                            idParrfo,
                            spTipoComentario.selectedItem.toString(),
                            etInserteComentario.text.toString()
                        )
                    )
                }

What I want is that when I insert the data it remains in the same position. I am using ViewModel

Answer 1

You are not correctly passing the data to Recycler View

Please make sure your Data Source is wrapped inside a Live Data And then pass this live data to your Recycler View Adapter.

This way Recycler View will only re-draw the changed item and not the entire list. Because Recycler View works well with Live Data.

Any method of Recycler View which will cause the list to re-draw should be excluded. for e.g. notifyDataSetChanged() method.

Instead call submitList()

And lastly please go through below documentation:

1. Recycler View Sample

2. RecyclerView.State