How to save RecyclerView's scroll position ? when app closed

Question

how i can save my last position in RecyclerView adapter after app closed and restore it after return to app

 RecyclerList.add(m);
        messageAdapter = new MessageAdapter(context, RecyclerList, leftUser, rightUser,  this);
        recyclerView.setAdapter(messageAdapter);
    }

    public void LoadData() {
        if (isNetworkAvailable()) {
            if (i < arrSplit.length) {
                recyclerListSize = RecyclerList.size();

                String temp = arrSplit[i];

                Data m = new Data(temp);

                RecyclerList.add(m);

                Objects.requireNonNull(recyclerView.getAdapter()).notifyItemInserted(recyclerListSize);
                recyclerView.smoothScrollToPosition(recyclerListSize);


                i++;
            } else {
              //

use SharedPrefrance to store last item pos in OnBindView() method , and return it when app open same page — Mahmoud Abu Alheja, Jan 19 '20 at 22:21
@Campbell : My problem is i have a recyclerview but when i go back or i close the app all contents start over :( i want to keep them even when i close the app Sorry for my english — Abdeel Elrai, Jan 19 '20 at 22:22
Are you asking [How to save RecyclerView's scroll position using RecyclerView.State?](https://stackoverflow.com/questions/27816217/how-to-save-recyclerviews-scroll-position-using-recyclerview-state) — Frank van Puffelen, Jan 19 '20 at 23:24

score 0 · Answer 1 · answered Jan 20 '20 at 08:05

Depending on what I understand you want store last position of item visible in your RecyclerView, so when back to app again scroll to last position before closed app/activity

First of all you can get last position from LayoutManger of RecyclerView like this

//define LinearLayoutManager object as global because we want to use in another method 
linearLayoutManager=new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);

and now we want to get last position and store it if activity is closed or go to background using life cycle activity call back

if you want know more about activity life cycle go to this

so inside onPause in your activity add store last position using SharedPrefrane

@Override
    protected void onPause() {
        super.onPause();            

        SharedPreferences preferences =getSharedPreferences("Pref",MODE_PRIVATE);

        //get last position Visible Item Position
        int lastPos= linearLayoutManager.findLastCompletelyVisibleItemPosition();

        //store lastPos
        preferences.edit().putInt("lastPos",lastPos).apply();

    }

know we store last position every time activity go to background or app closed

and after get data and set Adapter, retrieve the last position by add and call this method

private int getLastItemPosition(){

        SharedPreferences preferences =getSharedPreferences("Pref",MODE_PRIVATE);

        return preferences.getInt("lastPos",0);
    }

How to save RecyclerView's scroll position ? when app closed

1 Answers1