RecyclerView for chat app

Question

I'm building a chat app and present messages using RecyclerView. Since this a chat app, last messages should appear at the bottom of the list. To achieve this I use LinearManager in the following way:

    LinearLayoutManager layoutManager = new LinearLayoutManager(getContext());
    layoutManager.setOrientation(LinearLayoutManager.VERTICAL);
    layoutManager.setStackFromEnd(true);
    layoutManager.setSmoothScrollbarEnabled(false);

And it works fine if there are many messages in conversation. However, if there are only one or two messages between users, RecyclerView displays them at the bottom of the screen and puts white space above them.

Is it possible to display recycler items at the top of the screen in this case?

Answer 1

I create everything normal and added setStackFromEnd(true), setReverseLayout(true), and use this method bellow to set list to the bottom when it have many itens, the recyclerview will start from the bottom, otherwise it will aways show comments from the top even if it have less itens then the size of the screen.

//method will set the recyclerview to the end, in other words its going to the 
//end of the recyclerview, starting from the bottom.
//call scrollToBottom() after add your items in the adapter
public void scrollToBottom(){
    recyclerView.scrollVerticallyTo(0);
}

RecyclerView Java

RecyclerView recyclerView = (RecyclerView) findViewById(R.id.activity_comments_recycler_view);
LinearLayoutManager manager = LinearLayoutManager(this);
manager.setStackFromEnd(true);          
manager.setReverseLayout(true);         
recyclerView.setLayoutManager(manager); 

RecyclerView XML

<RecyclerView
    android:id="@+id/activity_comments_recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />