How to Build a Book Library App using Google Books API in Android?

package org.geeksforgeeks.demo;

import java.util.ArrayList;

public class BookInfo {

    // creating string, int and array list
    // variables for our book details
    private String title;
    private String subtitle;
    private ArrayList<String> authors;
    private String publisher;
    private String publishedDate;
    private String description;
    private int pageCount;
    private String thumbnail;
    private String previewLink;
    private String infoLink;
    private String buyLink;

    // creating getter and setter methods
    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getSubtitle() {
        return subtitle;
    }

    public void setSubtitle(String subtitle) {
        this.subtitle = subtitle;
    }

    public ArrayList<String> getAuthors() {
        return authors;
    }

    public void setAuthors(ArrayList<String> authors) {
        this.authors = authors;
    }

    public String getPublisher() {
        return publisher;
    }

    public void setPublisher(String publisher) {
        this.publisher = publisher;
    }

    public String getPublishedDate() {
        return publishedDate;
    }

    public void setPublishedDate(String publishedDate) {
        this.publishedDate = publishedDate;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public int getPageCount() {
        return pageCount;
    }

    public void setPageCount(int pageCount) {
        this.pageCount = pageCount;
    }

    public String getThumbnail() {
        return thumbnail;
    }

    public void setThumbnail(String thumbnail) {
        this.thumbnail = thumbnail;
    }

    public String getPreviewLink() {
        return previewLink;
    }

    public void setPreviewLink(String previewLink) {
        this.previewLink = previewLink;
    }

    public String getInfoLink() {
        return infoLink;
    }

    public void setInfoLink(String infoLink) {
        this.infoLink = infoLink;
    }

    public String getBuyLink() {
        return buyLink;
    }

    public void setBuyLink(String buyLink) {
        this.buyLink = buyLink;
    }

    // creating a constructor class for our BookInfo
    public BookInfo(String title, String subtitle, ArrayList<String> authors, String publisher,
                    String publishedDate, String description, int pageCount, String thumbnail,
                    String previewLink, String infoLink, String buyLink) {
        this.title = title;
        this.subtitle = subtitle;
        this.authors = authors;
        this.publisher = publisher;
        this.publishedDate = publishedDate;
        this.description = description;
        this.pageCount = pageCount;
        this.thumbnail = thumbnail;
        this.previewLink = previewLink;
        this.infoLink = infoLink;
        this.buyLink = buyLink;
    }
}

package org.geeksforgeeks.demo;

import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.Glide;

import java.util.ArrayList;

public class BookAdapter extends RecyclerView.Adapter<BookAdapter.BookViewHolder> {

    private final ArrayList<BookInfo> bookInfoArrayList;
    private final Context context;

    // Constructor to initialize adapter with data
    public BookAdapter(ArrayList<BookInfo> bookInfoArrayList, Context context) {
        this.bookInfoArrayList = bookInfoArrayList;
        this.context = context;
    }

    @NonNull
    @Override
    public BookViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        // Inflate layout for each RecyclerView item
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.book_rv_item, parent, false);
        return new BookViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull BookViewHolder holder, int position) {
        // Get current book info
        BookInfo bookInfo = bookInfoArrayList.get(position);

        // Set data to UI components
        holder.nameTV.setText(bookInfo.getTitle());
        holder.publisherTV.setText(bookInfo.getPublisher());
        holder.pageCountTV.setText("Pages : " + bookInfo.getPageCount());
        holder.dateTV.setText("Published On : " + bookInfo.getPublishedDate());

        // Load image from URL using Glide
        Glide.with(context).load(bookInfo.getThumbnail()).into(holder.bookIV);

        // Set click listener to open BookDetails activity with data
        holder.itemView.setOnClickListener(v -> {
            Intent intent = new Intent(context, BookDetails.class);
            intent.putExtra("title", bookInfo.getTitle());
            intent.putExtra("subtitle", bookInfo.getSubtitle());
            intent.putExtra("authors", bookInfo.getAuthors());
            intent.putExtra("publisher", bookInfo.getPublisher());
            intent.putExtra("publishedDate", bookInfo.getPublishedDate());
            intent.putExtra("description", bookInfo.getDescription());
            intent.putExtra("pageCount", bookInfo.getPageCount());
            intent.putExtra("thumbnail", bookInfo.getThumbnail());
            intent.putExtra("previewLink", bookInfo.getPreviewLink());
            intent.putExtra("infoLink", bookInfo.getInfoLink());
            intent.putExtra("buyLink", bookInfo.getBuyLink());

            // Start new activity with intent
            context.startActivity(intent);
        });
    }

    @Override
    public int getItemCount() {
        return bookInfoArrayList.size();
    }

    // ViewHolder class to hold UI elements for each item
    public static class BookViewHolder extends RecyclerView.ViewHolder {
        TextView nameTV, publisherTV, pageCountTV, dateTV;
        ImageView bookIV;

        public BookViewHolder(@NonNull View itemView) {
            super(itemView);
            // Initialize UI components
            nameTV = itemView.findViewById(R.id.bookTitle);
            publisherTV = itemView.findViewById(R.id.publisher);
            pageCountTV = itemView.findViewById(R.id.pageCount);
            dateTV = itemView.findViewById(R.id.date);
            bookIV = itemView.findViewById(R.id.bookImage);
        }
    }
}

package org.geeksforgeeks.demo;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import com.bumptech.glide.Glide;

public class BookDetails extends AppCompatActivity {

    // Declaring variables for book details
    private String title, subtitle, publisher, publishedDate, description, thumbnail, previewLink, infoLink, buyLink;
    private int pageCount;

    // UI components
    private TextView titleTV, subtitleTV, publisherTV, descTV, pageTV, publishDateTV;
    private Button previewBtn, buyBtn;
    private ImageView bookIV;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        EdgeToEdge.enable(this);
        setContentView(R.layout.activity_book_details);

        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main), (v, insets) -> {
            Insets systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars());
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
            return insets;
        });

        // Initializing views
        titleTV = findViewById(R.id.bookTitle);
        subtitleTV = findViewById(R.id.bookSubTitle);
        publisherTV = findViewById(R.id.publisher);
        descTV = findViewById(R.id.bookDescription);
        pageTV = findViewById(R.id.pageCount);
        publishDateTV = findViewById(R.id.publishedDate);
        previewBtn = findViewById(R.id.idBtnPreview);
        buyBtn = findViewById(R.id.idBtnBuy);
        bookIV = findViewById(R.id.bookImage);

        // Getting data passed from the adapter class
        Intent intent = getIntent();
        title = intent.getStringExtra("title");
        subtitle = intent.getStringExtra("subtitle");
        publisher = intent.getStringExtra("publisher");
        publishedDate = intent.getStringExtra("publishedDate");
        description = intent.getStringExtra("description");
        pageCount = intent.getIntExtra("pageCount", 0);
        thumbnail = intent.getStringExtra("thumbnail");
        previewLink = intent.getStringExtra("previewLink");
        infoLink = intent.getStringExtra("infoLink");
        buyLink = intent.getStringExtra("buyLink");

        // Setting data to UI components
        titleTV.setText(title);
        subtitleTV.setText(subtitle);
        publisherTV.setText(publisher);
        publishDateTV.setText("Published On : " + publishedDate);
        descTV.setText(description);
        pageTV.setText("Pages : " + pageCount);
        Glide.with(this).load(thumbnail).into(bookIV);

        // Adding click listener for preview button
        previewBtn.setOnClickListener(v -> {
            if (previewLink == null || previewLink.isEmpty()) {
                Toast.makeText(BookDetails.this, "No preview link present", Toast.LENGTH_SHORT).show();
                return;
            }
            Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(previewLink));
            startActivity(i);
        });

        // Adding click listener for buy button
        buyBtn.setOnClickListener(v -> {
            if (buyLink == null || buyLink.isEmpty()) {
                Toast.makeText(BookDetails.this, "No buy page present for this book", Toast.LENGTH_SHORT).show();
                return;
            }
            Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(buyLink));
            startActivity(i);
        });
    }
}

package org.geeksforgeeks.demo;

import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ProgressBar;
import android.widget.Toast;
import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;

// MainActivity handles the UI and API request
// to fetch books from Google Books API
public class MainActivity extends AppCompatActivity {

    // Variables for networking and UI components
    private RequestQueue mRequestQueue;
    private ArrayList<BookInfo> bookInfoArrayList;
    private ProgressBar progressBar;
    private EditText searchEdt;
    private ImageButton searchBtn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        EdgeToEdge.enable(this);
        setContentView(R.layout.activity_main);
        ViewCompat.setOnApplyWindowInsetsListener(findViewById(R.id.main), (v, insets) -> {
            Insets systemBars = insets.getInsets(WindowInsetsCompat.Type.systemBars());
            v.setPadding(systemBars.left, systemBars.top, systemBars.right, systemBars.bottom);
            return insets;
        });

        // Initializing UI components
        progressBar = findViewById(R.id.progressBar);
        searchEdt = findViewById(R.id.searchEditText);
        searchBtn = findViewById(R.id.searchButton);

        // Setting click listener on the search button
        searchBtn.setOnClickListener(v -> {
            
            // Show progress bar while searching
            progressBar.setVisibility(View.VISIBLE); 
            String query = searchEdt.getText().toString();
            if (query.isEmpty()) {
                
                // Error if input is empty
                searchEdt.setError("Please enter search query"); 
                return;
            }
            
            // Fetch books based on the search query
            getBooksInfo(query); 
        });
    }

    // Function to fetch book data from Google Books API
    private void getBooksInfo(String query) {
        
        // Initialize the book list
        bookInfoArrayList = new ArrayList<>(); 
        mRequestQueue = Volley.newRequestQueue(this);
        
        // Clear cache before making a new request
        mRequestQueue.getCache().clear(); 

        // Construct API URL using the search query
        String url = "https://www.googleapis.com/books/v1/volumes?q=" + query;
        RequestQueue queue = Volley.newRequestQueue(this);

        // Make API request to get book data
        JsonObjectRequest booksObjRequest = new JsonObjectRequest(Request.Method.GET, url, null,
                response -> {
                    
                    // Hide progress bar after fetching data
                    progressBar.setVisibility(View.GONE); 
                    try {
                        // Get book items array
                        JSONArray itemsArray = response.getJSONArray("items"); 
                        
                        for (int i = 0; i < itemsArray.length(); i++) {
                            JSONObject itemsObj = itemsArray.getJSONObject(i);
                            JSONObject volumeObj = itemsObj.getJSONObject("volumeInfo");

                            // Extract book details with default values
                            String title = volumeObj.optString("title", "N/A");
                            String subtitle = volumeObj.optString("subtitle", "N/A");
                            JSONArray authorsArray = volumeObj.optJSONArray("authors");
                            String publisher = volumeObj.optString("publisher", "N/A");
                            String publishedDate = volumeObj.optString("publishedDate", "N/A");
                            String description = volumeObj.optString("description", "N/A");
                            int pageCount = volumeObj.optInt("pageCount", 0);

                            // Get book thumbnail if available
                            JSONObject imageLinks = volumeObj.optJSONObject("imageLinks");
                            String thumbnail = (imageLinks != null) ? imageLinks.optString("thumbnail", "") : "";

                            // Get book preview and info links
                            String previewLink = volumeObj.optString("previewLink", "");
                            String infoLink = volumeObj.optString("infoLink", "");

                            // Get buy link from sale info (if available)
                            JSONObject saleInfoObj = itemsObj.optJSONObject("saleInfo");
                            String buyLink = (saleInfoObj != null) ? saleInfoObj.optString("buyLink", "") : "";

                            // Convert authors JSONArray to ArrayList<String>
                            ArrayList<String> authorsArrayList = new ArrayList<>();
                            if (authorsArray != null) {
                                for (int j = 0; j < authorsArray.length(); j++) {
                                    authorsArrayList.add(authorsArray.optString(j, "Unknown"));
                                }
                            }

                            // Create BookInfo object with fetched details
                            BookInfo bookInfo = new BookInfo(
                                    title, subtitle, authorsArrayList, publisher, publishedDate,
                                    description, pageCount, thumbnail, previewLink, infoLink, buyLink
                            );

                            // Add book details to the list
                            bookInfoArrayList.add(bookInfo);
                        }

                        // Set up RecyclerView with BookAdapter to display the book list
                        RecyclerView recyclerView = findViewById(R.id.rv);
                        recyclerView.setLayoutManager(new LinearLayoutManager(this));
                        BookAdapter adapter = new BookAdapter(bookInfoArrayList, this);
                        recyclerView.setAdapter(adapter);

                    } catch (JSONException e) {
                        e.printStackTrace();
                        Toast.makeText(this, "No Data Found: " + e.getMessage(), Toast.LENGTH_SHORT).show();
                    }
                },
                error -> {
                    // Handle API request error
                    Toast.makeText(this, "Error: " + error.getMessage(), Toast.LENGTH_SHORT).show();
                });

        // Add request to the Volley queue
        queue.add(booksObjRequest);
    }
}