Maintain the position of a RecyclerView when I add data

Good I have a problem that when adding data sends me to the beginning of the recycler when in fact what I want is to keep in the current position. This happens every time the user fills the end of the foot to load more data from volley ..

<android.support.v7.widget.RecyclerView
    android:id="@+id/recycler"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:scrollbars="vertical" />

the method that detects that it has reached the end

    recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
            if (!recyclerView.canScrollVertically(0)) {
                CargarContenido();
            }
        }
    });