Offline Load More Data with RecyclerView in android.

Step 1. Create a project step by step

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity">
<include layout="@layout/layout_toolbar" />
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recycleView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="8dp" />
</LinearLayout> 

 layout_toolbar.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical">
    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
        android:layout_height="?android:attr/actionBarSize"
        android:background="@color/purple_200"/>
</LinearLayout>

MainActivity.Java

public class MainActivity extends AppCompatActivity {
    private Toolbar mToolbar;
    private RecyclerView mRecyclerView;
    private List<UserModel> mUsers = new ArrayList<>();
    private UserAdapter mUserAdapter;

    public static OnLoadMoreListener mOnLoadMoreListener;

    public static boolean isLoading;

    private int visibleThreshold = 5;

    private int lastVisibleItem, totalItemCount;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        mToolbar.setTitle("LoadMoreRecycleView");
        for (int i = 0; i < 10; i++) {
            UserModel user = new UserModel();
            user.setName("Name " + i);
            user.setEmail("vimalku" + i + "@gmail.com");
            mUsers.add(user);
        }
        mRecyclerView = (RecyclerView) findViewById(R.id.recycleView);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
        mUserAdapter = new UserAdapter(this, mUsers);
        mRecyclerView.setAdapter(mUserAdapter);
        final LinearLayoutManager linearLayoutManager = (LinearLayoutManager) mRecyclerView.getLayoutManager();
        mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
            @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);
                totalItemCount = linearLayoutManager.getItemCount();
                lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition();
                if (!isLoading && totalItemCount <= (lastVisibleItem + visibleThreshold)) {
                    if (mOnLoadMoreListener != null) {
                        mOnLoadMoreListener.onLoadMore();
                    }
                    isLoading = true;
                }
            }
        });
        mUserAdapter.setOnLoadMoreListener(new OnLoadMoreListener() {
            @Override public void onLoadMore() {
                Log.e("haint", "Load More");
                mUsers.add(null);
                mUserAdapter.notifyItemInserted(mUsers.size() - 1);
                //Load more data for reyclerview
                new Handler().postDelayed(new Runnable() {
                    @Override public void run() {
                        Log.e("haint", "Load More 2");
                        //Remove loading item
                        mUsers.remove(mUsers.size() - 1);
                        mUserAdapter.notifyItemRemoved(mUsers.size());
                        //Load data
                        int index = mUsers.size();
                        int end = index + 10;
                        for (int i = index; i < end; i++) {
                            UserModel user = new UserModel();
                            user.setName("Name " + i);
                            user.setEmail("vimalku" + i + "@gmail.com");
                            mUsers.add(user);
                        }
                        mUserAdapter.notifyDataSetChanged();
                        mUserAdapter.setLoaded();
                    }
                }, 5000);
            }
        });
    }
    static class LoadingViewHolder extends RecyclerView.ViewHolder {
        public ProgressBar progressBar;
        public LoadingViewHolder(View itemView) {
            super(itemView);
            progressBar = (ProgressBar) itemView.findViewById(R.id.progressBar1);
        }
    }

}

layout_user_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    card_view:cardCornerRadius="5dp"
    card_view:cardUseCompatPadding="true">
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="?android:selectableItemBackground">
        <TextView android:id="@+id/tvName"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="5dp"
            android:text="Name"
            android:textColor="@android:color/black"
            android:textSize="18sp" />
        <TextView android:id="@+id/tvEmailId"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/tvName"
            android:layout_margin="5dp"
            android:text="Email Id"
            android:textColor="@android:color/black"
            android:textSize="12sp" />
    </RelativeLayout>
</androidx.cardview.widget.CardView>  

layout_loading_item.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <ProgressBar android:id="@+id/progressBar1"
        android:layout_width="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_height="wrap_content" />
</LinearLayout>

  

UserAdapter.Java:

class UserAdapter extends RecyclerView.Adapter <RecyclerView.ViewHolder > {
    private Context context;
    private List<UserModel> mUsers;

    private final int VIEW_TYPE_ITEM = 0;

    private final int VIEW_TYPE_LOADING = 1;

    public UserAdapter(Context context, List<UserModel> mUsers) {
        this.context = context;
        this.mUsers = mUsers;
    }

    public void setOnLoadMoreListener(OnLoadMoreListener mOnLoadMoreListener) {
        MainActivity.mOnLoadMoreListener = mOnLoadMoreListener;
    }
    @Override public int getItemViewType(int position) {
        return mUsers.get(position) == null ? VIEW_TYPE_LOADING : VIEW_TYPE_ITEM;
    }
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType == VIEW_TYPE_ITEM) {
            View view = LayoutInflater.from(context).inflate(R.layout.layout_user_item, parent, false);
            return new UserViewHolder(view);
        } else if (viewType == VIEW_TYPE_LOADING) {
            View view = LayoutInflater.from(context).inflate(R.layout.layout_loading_item, parent, false);
            return new MainActivity.LoadingViewHolder(view);
        }
        return null;
    }
    @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        if (holder instanceof UserViewHolder) {
            UserModel user = mUsers.get(position);
            UserViewHolder userViewHolder = (UserViewHolder) holder;
            userViewHolder.tvName.setText(user.getName());
            userViewHolder.tvEmailId.setText(user.getEmail());
        } else if (holder instanceof MainActivity.LoadingViewHolder) {
            MainActivity.LoadingViewHolder loadingViewHolder = (MainActivity.LoadingViewHolder) holder;
            loadingViewHolder.progressBar.setIndeterminate(true);
        }
    }
    @Override
    public int getItemCount() {
        return mUsers == null ? 0 : mUsers.size();
    }

    static class UserViewHolder extends RecyclerView.ViewHolder {
        public TextView tvName;
        public TextView tvEmailId;
        public UserViewHolder(View itemView) {
            super(itemView);
            tvName = (TextView) itemView.findViewById(R.id.tvName);
            tvEmailId = (TextView) itemView.findViewById(R.id.tvEmailId);
        }
    }
    public void setLoaded() {
        MainActivity.isLoading = false;
    }
}

UserModel.Java:

public class UserModel {
    private String name;
    private String email;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
}

OnLoadMoreListener interface:

public interface OnLoadMoreListener {
    void onLoadMore();
}