The LayoutManager, which is responsible in the RecyclerView for rendering where items should be positioned and manages scrolling, provides information about the current scroll position relative to the adapter. We can use a similar approach with the RecyclerView by defining an interface EndlessRecyclerViewScrollListener that requires an onLoadMore() method to be implemented. You can see this guide for more information. For more advanced cases, Google released its own Paging Library. For Android University courses it's recommended to use this approach for simplicity.
NOTE: This page is describing a straightforward yet a bit dated solution. Adding a threshold value therefore helps anticipate the need to append more data. To provide the appearance of endless scrolling, it's important to fetch data before the user gets to the end of the list. This data can be used to decide when to load more data from an external source: In both cases, the information needed to implement the scrolling include determining the last visible item within the list and some type of threshold value to start fetching more data before the last item has been reached. Both are similar in code except that the LayoutManager in the RecyclerView needs to be passed in to provide the necessary information to implement infinite scrolling. The approaches for ListView, GridView and RecyclerView (the successor to ListView) are documented here. This is done by triggering a request for more data once the user crosses a threshold of remaining items before they've hit the end. A common application feature is to load automatically more items as the user scrolls through the items (aka infinite scroll).
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