Book Search Tutorial
In this tutorial, we'll make an app that searches the OpenLibrary API to search books and display cover images. It also allows you to recommend books to friends.
The app is composed of two screens. The first screen displays a list of books, in which, each book is described by its title, author and cover photo. After a user selects a book from the list, a second screen appears displaying additional details about the book, including the publisher and no. of pages.
Book List
Book Details
The full source code for this app can be downloaded here for review as well.
- How to access a typical RESTful API?
- How to parse JSON results and understand JSON format?
- How to add SearchView to ActionBar to search books?
- How to use ProgressBar?
- How to use explicit and implicit intents?
- How to communicate data between apps using intents?
- How to share remote images?
Create a new project in Android Studio and call it 'BookSearch'. Select the defaults and rename 'MainActivity' to 'BookListActivity'.
Let's setup the android-async-http-client for sending asynchronous network requests.
Let's also install a library for remote image loading called Picasso so we can easily display cover images.
Open your build.gradle file and add these libraries as dependencies that can be downloaded via a remote repository:
repositories {
jcenter()
}
dependencies {
// ...
compile 'com.loopj.android:android-async-http:1.4.9'
compile 'com.squareup.picasso:picasso:2.5.2'
}Then you need to sync with gradle and make sure there are no errors.
We'll be using the following icon for our app.
We'll use the following image when the cover image is not available.
Copy and paste both ic_launcher.png and ic_nocover.png into res/drawable for use later.
Add the proper internet permissions to the AndroidManifest.xml within the manifest node:
<uses-permission android:name="android.permission.INTERNET" />Once you add this, network requests can be executed.
In the res/layout/activity_book_list.xml, lets drop out a ListView with the id lvBooks:
<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=".BookListActivity">
<ListView
android:id="@+id/lvBooks"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
Let's generate a Java class that will act as our OpenLibrary API client for sending out network requests to specific endpoints. Create a Java class called BookClient with the following code:
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();
}
}
}Looking at the JSON response format for the OpenLibrary search API, we can understand what information we will be provided:
[
{
"title_suggest":"Lord of the Rings",
"edition_key":[
"OL9409698M",
"OL10957365M",
"OL10957364M",
"OL9314653M",
"OL9701406M"
],
"cover_i":1454705,
"isbn":[
"0768325293",
"9780768374698",
"9780768325782",
"9780768325249",
"9780768325294",
"0768325242",
"0768325234",
"0768374693",
"0768325781",
"9780768325232"
],
"has_fulltext":false,
"text":[
"OL9409698M",
"OL10957365M",
"OL10957364M",
"OL9314653M",
"OL9701406M",
"0768325293",
"9780768374698",
"9780768325782",
"9780768325249",
"9780768325294",
"0768325242",
"0768325234",
"0768374693",
"0768325781",
"9780768325232",
"Cedco Publishing",
"OL2853379A",
"Journal # 4 (Lord of the Rings)",
"Trilogy Edition 2006 Calendar (Cedco Mini Daily)",
"Journal # 3 (Lord of the Rings)",
"Lord of the Rings",
"\/works\/OL8527426W",
"Cedco Publishing Company",
"The Lord of the Rings"
],
"author_name":[
"Cedco Publishing"
],
"seed":[
"\/books\/OL9409698M",
"\/books\/OL10957365M",
"\/books\/OL10957364M",
"\/books\/OL9314653M",
"\/books\/OL9701406M",
"\/works\/OL8527426W",
"\/authors\/OL2853379A"
],
"author_key":[
"OL2853379A"
],
"title":"Lord of the Rings",
"publish_date":[
"August 30, 2005",
"September 2002",
"October 2001"
],
"type":"work",
"ebook_count_i":0,
"edition_count":5,
"key":"\/works\/OL8527426W",
"id_goodreads":[
"130022",
"5984308",
"59318"
],
"publisher":[
"Cedco Publishing Company"
],
"language":[
"eng"
],
"last_modified_i":1282021198,
"id_librarything":[
"4607237"
],
"cover_edition_key":"OL9701406M",
"publish_year":[
2002,
2001,
2005
],
"first_publish_year":2001
},
{
"title_suggest":"Ring out, wild bells",
...
}
]Next, let's define a model that represents the relevant data for a single book. This object needs to contain basic info for each book such as title, author, cover image and an openLibraryId. Create a Java class called Book with the relevant attributes defined.
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";
}
}Note that by default Covers API returns a blank image if the cover cannot be found. If you append ?default=false to the end of the URL, then it returns a 404 instead. This is important because we want to display an error drawable in case the cover cannot be found.
Next, let's add a factory method for deserializing the JSON response in order to construct an instance of the Book class:
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 "";
}
}
}Let's also add a convenience static method for parsing an array of JSON book dictionaries into an ArrayList which we will use to manage the OpenLibrary search API endpoint response:
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;
}
}Now, we have the API Client (BookClient) and the data Model object (Book). Final step is to construct an adapter that allows us to translate a Book into a particular view. Let's generate a Java class called BookAdapter which extends from ArrayAdapter<Book>:
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;
}
}Now, we need to define a layout to use for visualizing a particular book. Let's create a layout file called item_book.xml with a RelativeLayout root layout for defining the book row layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<ImageView
android:id="@+id/ivBookCover"
android:layout_width="56dp"
android:layout_height="56dp"
android:layout_margin="8dp" />
<TextView
android:id="@+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:layout_toRightOf="@+id/ivBookCover"
android:text="Title"
android:textSize="24dp" />
<TextView
android:id="@+id/tvAuthor"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="8dp"
android:layout_toRightOf="@+id/ivBookCover"
android:layout_below="@+id/tvTitle"
android:text="Author"
android:textSize="12dp" />
</RelativeLayout>and now we can fill in the getView method to finish off the BookAdapter:
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;
}
}Now that we have defined the adapter, let's plug all of these components together within the BookListActivity by using the client to send out an API call, deserialize the response into an array of Book object and then render those into a ListView using the BookAdapter. Let's start by initializing the ArrayList, adapter, and the ListView:
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);
}
}Now let's make the call to the book search API from the activity using our client:
public class BookListActivity extends AppCompatActivity {
...
import cz.msebera.android.httpclient.Header;
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();
}
}
});
}
}After running the app, we should see the following output:
Note that the search query is hardcoded in fetchBooks() method. We'll fix this shortly. In the next step, we'll add SearchView to ActionBar and pass the query entered in the SearchView to retrieve the books from OpenLibrary search API.
We can use a SearchView to search for a book by its author or title. Using the SearchView widget as an item in the ActionBar is the preferred way to provide search in Android. To add SearchView to your ActionBar, add the SearchView action item in menu_book_list.xml file.
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
tools:context=".BookListActivity">
<item
android:id="@+id/action_search"
android:title="Search"
android:icon="@android:drawable/ic_menu_search"
app:showAsAction="always"
app:actionViewClass="android.support.v7.widget.SearchView" />
</menu>If you run your app now, the SearchView appears in the app's action bar, but it isn't functional.
Now we need to hook up a listener for when a search is performed in BookListActivity.java. Also note that we modified fetchBooks() method to accept the search query and removed the call to fetch books from onCreate().
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;
}
}You should now be able to search for books from the SearchView in your ActionBar.
A ProgressBar should be used when we want the user to wait till a task completes. It's a good practice to always show a ProgressBar before making a network call.
To display an indeterminate ProgressBar, add a ProgressBar to activity_book_list.xml file.
<LinearLayout
...>
<ProgressBar
android:id="@+id/progress"
android:layout_width="match_parent"
android:layout_height="wrap_content"
style="?android:attr/progressBarStyleHorizontal"
android:max="100"
android:indeterminate="true"
android:visibility="gone" />
<ListView
... />
</LinearLayout>In BookListActivity.java, show ProgressBar before calling the search API and hide it when you receive the results back from the server.
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);
}
});
}
}Let's add a detail view which would display more details about a book when the book was selected within the list. In order to achieve that we would need to:
- Generate an activity for the details view
- Define the detail Layout XML with views
- Setup an item click listener for the list of books
- Fire an intent when a user selects a book from the list
- Pass the book through the intent and populate the detail view
First, let's generate an activity to display book details and name it BookDetailActivity.java. Edit the layout file activity_book_detail.xml to include book details and a cover photo.
<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=".BookListActivity">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:gravity="center_horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<ImageView
android:id="@+id/ivBookCover"
android:layout_marginTop="8dp"
android:layout_width="280dp"
android:layout_height="280dp" />
<TextView
android:id="@+id/tvTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="32sp"
android:layout_marginTop="8dp"
android:paddingLeft="10dp"
android:paddingRight="10dp" />
<TextView
android:id="@+id/tvAuthor"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="22sp"
android:layout_marginTop="8dp" />
<View
android:background="@android:color/darker_gray"
android:layout_width="280dp"
android:layout_height="1px"
android:layout_marginTop="8dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:text="Published By"
android:textSize="14sp" />
<TextView
android:id="@+id/tvPublisher"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="14sp" />
<TextView
android:id="@+id/tvPageCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:textSize="14sp" />
</LinearLayout>
</ScrollView>
</LinearLayout>Next, we want to be able to pass the book object from the list to this detail view, so let's make our Book class serializable:
public class Book implements Serializable {
...
}Let's now add an item click handler to our BookListActivity.java which will launch the detail view with an intent:
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);
}
});
}
...
}In addition to title, author and cover photo, let's also display the no. of pages in a book and its publisher. To fetch this data, we need to call the OpenLibrary Books API. Add a method to BookClient.java to fetch extra details of a book.
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);
}
}Now, let's populate the data from the book into the details view with BookDetailActivity.java:
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);
}
}If you run your app now, your detail screen should look similar to this:
Let's use an implicit intent ACTION_SEND to share a book with your friends. We'll share book title and cover photo.
Start by adding a menu item in menu_book_detail.xml.
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context=".BookListActivity">
<item
android:id="@+id/action_share"
app:showAsAction="ifRoom"
android:icon="@android:drawable/ic_menu_share"
android:title="Share" />
</menu> Trigger a share intent and bring up the share menu on click of share menu item. Also note how remote images are shared using shared intent.
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(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_DOWNLOADS), "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;
}
}Here, getLocalBitmapUri() extracts the bitmap from the ImageView and loads it into a file in the default extranl storage directory. To do this, the app will need certain permissions.
Make sure to add the appropriate permissions to your AndroidManifest.xml:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />Here's the final detail view with share icon:
Tap the share icon and the share menu appears:
