Book Search Tutorial - meswapnilwagh/android_guides GitHub Wiki

public class BookClient {
  private static final String API_BASE_URL = "http://openlibrary.org/";
  private AsyncHttpClient client;

  public BookClient() {
    this.client = new AsyncHttpClient();
  }

  private String getApiUrl(String relativeUrl) {
    return API_BASE_URL + relativeUrl;
  }

  // Method for accessing the search API
  public void getBooks(final String query, JsonHttpResponseHandler handler) {
    try {
      String url = getApiUrl("search.json?q=");
      client.get(url + URLEncoder.encode(query, "utf-8"), handler);
    } catch (UnsupportedEncodingException e) {
      e.printStackTrace();
    }
  }
}

public class Book {
  private String openLibraryId;
  private String author;
  private String title;

  public String getOpenLibraryId() {
    return openLibraryId;
  }

  public String getTitle() {
    return title;
  }

  public String getAuthor() {
    return author;
  }

  // Get medium sized book cover from covers API
  public String getCoverUrl() {
    return "http://covers.openlibrary.org/b/olid/" + openLibraryId + "-M.jpg?default=false";
  }

  // Get large sized book cover from covers API
  public String getLargeCoverUrl() {
    return "http://covers.openlibrary.org/b/olid/" + openLibraryId + "-L.jpg?default=false";
  }
}

public class Book {
  ...

  // Returns a Book given the expected JSON
  public static Book fromJson(JSONObject jsonObject) {
    Book book = new Book();
    try {
      // Deserialize json into object fields
      // Check if a cover edition is available
      if (jsonObject.has("cover_edition_key"))  {
        book.openLibraryId = jsonObject.getString("cover_edition_key");
      } else if(jsonObject.has("edition_key")) {
        final JSONArray ids = jsonObject.getJSONArray("edition_key");
        book.openLibraryId = ids.getString(0);
      }
      book.title = jsonObject.has("title_suggest") ? jsonObject.getString("title_suggest") : "";
      book.author = getAuthor(jsonObject);
    } catch (JSONException e) {
      e.printStackTrace();
      return null;
    }
    // Return new object
    return book;
  }

  // Return comma separated author list when there is more than one author
  private static String getAuthor(final JSONObject jsonObject) {
    try {
      final JSONArray authors = jsonObject.getJSONArray("author_name");
      int numAuthors = authors.length();
      final String[] authorStrings = new String[numAuthors];
      for (int i = 0; i < numAuthors; ++i) {
        authorStrings[i] = authors.getString(i);
      }
      return TextUtils.join(", ", authorStrings);
    } catch (JSONException e) {
      return "";
    }
  }
}

public class Book {
  ...

  // Decodes array of book json results into business model objects
  public static ArrayList<Book> fromJson(JSONArray jsonArray) {
    ArrayList<Book> books = new ArrayList<Book>(jsonArray.length());
    // Process each result in json array, decode and convert to business
    // object
    for (int i = 0; i < jsonArray.length(); i++) {
      JSONObject bookJson = null;
      try {
        bookJson = jsonArray.getJSONObject(i);
      } catch (Exception e) {
        e.printStackTrace();
        continue;
      }
      Book book = Book.fromJson(bookJson);
      if (book != null) {
        books.add(book);
      }
    }
    return books;
  }
}

public class BookAdapter extends ArrayAdapter<Book> {

  public BookAdapter(Context context, ArrayList<Book> aBooks) {
    super(context, 0, aBooks);
  }

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    // TODO: Complete the definition of the view for each book
    return null;
  }
}

public class BookAdapter extends ArrayAdapter<Book> {
  // View lookup cache
  private static class ViewHolder {
    public ImageView ivCover;
    public TextView tvTitle;
    public TextView tvAuthor;
  }

  public BookAdapter(Context context, ArrayList<Book> aBooks) {
    super(context, 0, aBooks);
  }

  // Translates a particular `Book` given a position
  // into a relevant row within an AdapterView
  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    // Get the data item for this position
    final Book book = getItem(position);
    // Check if an existing view is being reused, otherwise inflate the view
    ViewHolder viewHolder; // view lookup cache stored in tag
    if (convertView == null) {
      viewHolder = new ViewHolder();
      LayoutInflater inflater = (LayoutInflater)getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
      convertView = inflater.inflate(R.layout.item_book, parent, false);
      viewHolder.ivCover = (ImageView)convertView.findViewById(R.id.ivBookCover);
      viewHolder.tvTitle = (TextView)convertView.findViewById(R.id.tvTitle);
      viewHolder.tvAuthor = (TextView)convertView.findViewById(R.id.tvAuthor);
      convertView.setTag(viewHolder);
    } else {
      viewHolder = (ViewHolder) convertView.getTag();
    }
    // Populate the data into the template view using the data object
    viewHolder.tvTitle.setText(book.getTitle());
    viewHolder.tvAuthor.setText(book.getAuthor());
    Picasso.with(getContext()).load(Uri.parse(book.getCoverUrl())).error(R.drawable.ic_nocover).into(viewHolder.ivCover);
    // Return the completed view to render on screen
    return convertView;
  }
}

public class BookListActivity extends AppCompatActivity {
  private ListView lvBooks;
  private BookAdapter bookAdapter;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_book_list);
    lvBooks = (ListView) findViewById(R.id.lvBooks);
    ArrayList<Book> aBooks = new ArrayList<Book>();
    bookAdapter = new BookAdapter(this, aBooks);
    lvBooks.setAdapter(bookAdapter);
  }
}

...
import cz.msebera.android.httpclient.Header;
...
public class BookListActivity extends AppCompatActivity {
  ...
  private BookClient client;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    ...
    // Fetch the data remotely
    fetchBooks();
  }

  // Executes an API call to the OpenLibrary search endpoint, parses the results
  // Converts them into an array of book objects and adds them to the adapter
  private void fetchBooks() {
    client = new BookClient();
    client.getBooks("oscar Wilde", new JsonHttpResponseHandler() {
      @Override
      public void onSuccess(int statusCode, Header[] headers, JSONObject response) {
        try {
          JSONArray docs = null;
          if(response != null) {
            // Get the docs json array
            docs = response.getJSONArray("docs");
            // Parse json array into array of model objects
            final ArrayList<Book> books = Book.fromJson(docs);
            // Remove all books from the adapter
            bookAdapter.clear();
            // Load model objects into the adapter
            for (Book book : books) {
              bookAdapter.add(book); // add book through the adapter
            }
            bookAdapter.notifyDataSetChanged();
          }
        } catch (JSONException e) {
          // Invalid JSON format, show appropriate error.
          e.printStackTrace();
        }
      }
    });
  }
}

public class BookListActivity extends AppCompatActivity {
  ...

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    ...
    // Fetch the data remotely
    // fetchBooks();
  }

  // Executes an API call to the OpenLibrary search endpoint, parses the results
  // Converts them into an array of book objects and adds them to the adapter
  private void fetchBooks(String query) {
    client = new BookClient();
    client.getBooks(query, new JsonHttpResponseHandler() {
      ...
    });
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_book_list, menu);
    final MenuItem searchItem = menu.findItem(R.id.action_search);
    final SearchView searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
      @Override
      public boolean onQueryTextSubmit(String query) {
        // Fetch the data remotely
        fetchBooks(query);
        // Reset SearchView
        searchView.clearFocus();
        searchView.setQuery("", false);
        searchView.setIconified(true);
        searchItem.collapseActionView();
        // Set activity title to search query
        BookListActivity.this.setTitle(query);
        return true;
      }

      @Override
      public boolean onQueryTextChange(String s) {
        return false;
      }
    });
    return true;
  }
}

public class BookListActivity extends AppCompatActivity {
  ...
  private ProgressBar progress;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    ...
    progress = (ProgressBar) findViewById(R.id.progress);
  }

  // Executes an API call to the OpenLibrary search endpoint, parses the results
  // Converts them into an array of book objects and adds them to the adapter
  private void fetchBooks(String query) {
    // Show progress bar before making network request
    progress.setVisibility(ProgressBar.VISIBLE);
    ...

    client.getBooks(query, new JsonHttpResponseHandler() {
      @Override
      public void onSuccess(int statusCode, Header[] headers, JSONObject response) {
        try {
          // hide progress bar
          progress.setVisibility(ProgressBar.GONE);
          ...
        } catch (JSONException e) {
          // Invalid JSON format, show appropriate error.
          e.printStackTrace();
        }
      }

      @Override
      public void onFailure(int statusCode, Header[] headers, String responseString, Throwable throwable) {
        progress.setVisibility(ProgressBar.GONE);
      }
    });
  }
}

public class Book implements Serializable {
  ...
}

public class BookListActivity extends AppCompatActivity {
  public static final String BOOK_DETAIL_KEY = "book";
  ...

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    ...
    setupBookSelectedListener();
  }

  public void setupBookSelectedListener() {
    lvBooks.setOnItemClickListener(new AdapterView.OnItemClickListener() {
      @Override
      public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        // Launch the detail view passing book as an extra
        Intent intent = new Intent(BookListActivity.this, BookDetailActivity.class);
        intent.putExtra(BOOK_DETAIL_KEY, bookAdapter.getItem(position));
        startActivity(intent);
      }
    });
  }

  ...
}

public class BookClient {
  ...

  // Method for accessing books API to get publisher and no. of pages in a book.
  public void getExtraBookDetails(String openLibraryId, JsonHttpResponseHandler handler) {
    String url = getApiUrl("books/");
    client.get(url + openLibraryId + ".json", handler);
  }
}

public class BookDetailActivity extends AppCompatActivity {
  private ImageView ivBookCover;
  private TextView tvTitle;
  private TextView tvAuthor;
  private TextView tvPublisher;
  private TextView tvPageCount;
  private BookClient client;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_book_detail);
    // Fetch views
    ivBookCover = (ImageView) findViewById(R.id.ivBookCover);
    tvTitle = (TextView) findViewById(R.id.tvTitle);
    tvAuthor = (TextView) findViewById(R.id.tvAuthor);
    tvPublisher = (TextView) findViewById(R.id.tvPublisher);
    tvPageCount = (TextView) findViewById(R.id.tvPageCount);
    // Use the book to populate the data into our views
    Book book = (Book) getIntent().getSerializableExtra(BookListActivity.BOOK_DETAIL_KEY);
    loadBook(book);
  }

  // Populate data for the book
  private void loadBook(Book book) {
    //change activity title
    this.setTitle(book.getTitle());
    // Populate data
    Picasso.with(this).load(Uri.parse(book.getLargeCoverUrl())).error(R.drawable.ic_nocover).into(ivBookCover);
    tvTitle.setText(book.getTitle());
    tvAuthor.setText(book.getAuthor());
    // fetch extra book data from books API
    client = new BookClient();
    client.getExtraBookDetails(book.getOpenLibraryId(), new JsonHttpResponseHandler() {
      @Override
      public void onSuccess(int statusCode, Header[] headers, JSONObject response) {
        try {
          if (response.has("publishers")) {
            // display comma separated list of publishers
            final JSONArray publisher = response.getJSONArray("publishers");
            final int numPublishers = publisher.length();
            final String[] publishers = new String[numPublishers];
            for (int i = 0; i < numPublishers; ++i) {
              publishers[i] = publisher.getString(i);
            }
            tvPublisher.setText(TextUtils.join(", ", publishers));
          }
          if (response.has("number_of_pages")) {
            tvPageCount.setText(Integer.toString(response.getInt("number_of_pages")) + " pages");
          }
        } catch (JSONException e) {
          e.printStackTrace();
        }
      }
      });
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
      // Inflate the menu; this adds items to the action bar if it is present.
      getMenuInflater().inflate(R.menu.menu_book_detail, menu);
      return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
      // Handle action bar item clicks here. The action bar will
      // automatically handle clicks on the Home/Up button, so long
      // as you specify a parent activity in AndroidManifest.xml.
      int id = item.getItemId();

      //noinspection SimplifiableIfStatement
      if (id == R.id.action_settings) {
        return true;
      }

      return super.onOptionsItemSelected(item);
    }
}

public class BookDetailActivity extends AppCompatActivity {
  ...

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    if (id == R.id.action_share) {
      setShareIntent();
      return true;
    }
    return super.onOptionsItemSelected(item);
  }

  private void setShareIntent() {
    ImageView ivImage = (ImageView) findViewById(R.id.ivBookCover);
    final TextView tvTitle = (TextView)findViewById(R.id.tvTitle);
    // Get access to the URI for the bitmap
    Uri bmpUri = getLocalBitmapUri(ivImage);
    // Construct a ShareIntent with link to image
    Intent shareIntent = new Intent();
    // Construct a ShareIntent with link to image
    shareIntent.setAction(Intent.ACTION_SEND);
    shareIntent.setType("*/*");
    shareIntent.putExtra(Intent.EXTRA_TEXT, (String)tvTitle.getText());
    shareIntent.putExtra(Intent.EXTRA_STREAM, bmpUri);
    // Launch share menu
    startActivity(Intent.createChooser(shareIntent, "Share Image"));
  }

  // Returns the URI path to the Bitmap displayed in cover imageview
  public Uri getLocalBitmapUri(ImageView imageView) {
    // Extract Bitmap from ImageView drawable
    Drawable drawable = imageView.getDrawable();
    Bitmap bmp = null;
    if (drawable instanceof BitmapDrawable){
      bmp = ((BitmapDrawable) imageView.getDrawable()).getBitmap();
    } else {
      return null;
    }
    // Store image to default external storage directory
    Uri bmpUri = null;
    try {
      File file =  new File(getExternalFilesDir(Environment.DIRECTORY_PICTURES),
         "share_image_" + System.currentTimeMillis() + ".png");
      file.getParentFile().mkdirs();
      FileOutputStream out = new FileOutputStream(file);
      bmp.compress(Bitmap.CompressFormat.PNG, 90, out);
      out.close();
      bmpUri = Uri.fromFile(file);
    } catch (IOException e) {
      e.printStackTrace();
    }
    return bmpUri;
  }
}