Firebase android pagination

Question

I\'m building an app which will show videos stored on firebase. The list of videos needs to be paginated fetching most recent 20 videos at a time.

Here is

Answer 1

You can achieve it by using Firebase database paging library as below code... In this code, I have shown Post as an data model item and PostViewHolder as ViewHolder

        //Initialize RecyclerView
        mRecyclerView = findViewById(R.id.recycler_view);
        mRecyclerView.setHasFixedSize(true);

        LinearLayoutManager mManager = new LinearLayoutManager(this);
        mRecyclerView.setLayoutManager(mManager);

        //Initialize Database
        mDatabase = FirebaseDatabase.getInstance().getReference().child("posts");

        //Initialize PagedList Configuration
        PagedList.Config config = new PagedList.Config.Builder()
                .setEnablePlaceholders(false)
                .setPrefetchDistance(5)
                .setPageSize(10)
                .build();

        //Initialize FirebasePagingOptions
        DatabasePagingOptions options = new DatabasePagingOptions.Builder()
                .setLifecycleOwner(this)
                .setQuery(mDatabase, config, Post.class)
                .build();

        //Initialize Adapter
        mAdapter = new FirebaseRecyclerPagingAdapter(options) {
            @NonNull
            @Override
            public PostViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
                return new PostViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.item_list, parent, false));
            }

            @Override
            protected void onBindViewHolder(@NonNull PostViewHolder holder,
                                            int position,
                                            @NonNull Post model) {
                holder.setItem(model);
            }

            @Override
            protected void onLoadingStateChanged(@NonNull LoadingState state) {
                switch (state) {
                    case LOADING_INITIAL:
                    case LOADING_MORE:
                        // Do your loading animation
                        mSwipeRefreshLayout.setRefreshing(true);
                        break;

                    case LOADED:
                        // Stop Animation
                        mSwipeRefreshLayout.setRefreshing(false);
                        break;

                    case FINISHED:
                        //Reached end of Data set
                        mSwipeRefreshLayout.setRefreshing(false);
                        break;

                    case ERROR:
                        retry();
                        break;
                }
            }

            @Override
            protected void onError(@NonNull DatabaseError databaseError) {
                super.onError(databaseError);
                mSwipeRefreshLayout.setRefreshing(false);
                databaseError.toException().printStackTrace();
            }
        };

        //Set Adapter to RecyclerView
        mRecyclerView.setAdapter(mAdapter);

Just visit this below URL for reference https://firebaseopensource.com/projects/patilshreyas/firebaserecyclerpagination/app/readme.md/ Here you will find implementation of library which helps to implement Pagination of firebase data in RecyclerView

I hope this will help you!