Firestore chat app using Firebase-UI (Android)

Question

I am trying to create a chat using the Firebase-UI library for Cloud Firestore. This github repository contains the relevant code which I am using. The problem comes with th

Answer 1

To solve this, you can use the following query:

Query sChatQuery = sChatCollection
    .orderBy("timestamp", Query.Direction.ASCENDING)
    .whereGreaterThanOrEqualTo("timestamp', desiredTime)
    .limit(50);

If you are using a RecyclerView to display data, the simplest way would be to use the following code:

LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
layoutManager.setReverseLayout(true);
layoutManager.setStackFromEnd(true);
recyclerView.setLayoutManager(layoutManager);

This approch will reverse you the order as you want.

Another approach would be to create your own adapter that extends FirebaseListAdapter and override getItem() method like this:

@Override
public HashMap getItem(int pos) {
    return super.getItem(getCount() - 1 - pos);
}

Another approach would be to get the data from the database, add it to a Collection, a List would be a good solution and then use Collections.reverse(yourList);.