<p>This sample demonstrates how an application can make use of shared code and
resources stored in an Android library project.</p>

<p>In this case, the TicTacToeMain application project includes a reference to
the TicTacToeLib library project. When you build the TicTacToeMain application,
the build tools look for the library project and compile it's code and resources
as part of the main application's <code>.apk</code> file. The main application
is designed with a launcher activity called <code>MainActivity</code>, shown at
left, below. When the user presses a button in the View,
<code>MainActivity</code> starts a second activity, <code>GameActivity</code>,
which is declared in the library project. </p>

<ul>
<li>The main application's <a
href="AndroidManifest.html">AndroidManifest.xml</a> file contains declarations
of both <code>MainActivity</code>, which is implemented locally in main project,
and <code>GameActivity</code>, which is implemented in the library project.
Currently, an application must declare in its manifest any components or
resources that it is using from a library project.</li>
<li><a
href="src/com/example/android/tictactoe/MainActivity.html">MainActivity.java</a>
shows how a class in the main application imports and uses
classes from the library project. The Activity sets listeners on the buttons in
the main View and, when one of them is clicked, creates an explicit Intent
targeted at the <code>GameActivity</code> component declared in the TicTacToeLib
library project. </li>
</ul>

<p>The TicTacToeLib library project includes a single Activity,
<code>GameActivity</code>, that handles most of the application lifecycle.</p>

<ul>
<li>The library project includes an <a
href="../TicTacToeLib/AndroidManifest.html">AndroidManifest.xml</a> file that
declares <code>GameActivity</code>.</li>
<li><a
href="../TicTacToeLib/src/com/example/android/tictactoe/library/GameActivity.html">GameActivity.java</a>
handles most of the application lifecycle and manages general game play.</li>
<li><a
href="../TicTacToeLib/src/com/example/android/tictactoe/library/GameView.html">GameView.java</a>
renders the UI of the game and manages interaction events during game play.</li>
</ul>

<p>If you want to build the TicTacToeMain application, you can obtain it by
downloading the "Samples for SDK API 8" component (or higher version) into your
SDK, using the <em>Android SDK and AVD Manager</em>. Note that the application
project depends on code and resources found in the TicTacToeLib library project
&mdash; in order to build TicTacToeMain, you need to add both projects to your
development environment. </p>

<p>To build an application that uses a library project, you also need to update
to the latest version of the SDK tools (r6 or higher) and Android platforms, as
well as the latest version of ADT (0.9.7 or higher), if you are developing in
Eclipse. </p>

<p>For information about how to set up Android library projects, refer to
<a href="../../../guide/developing/eclipse-adt.html#libraryProject">Developing
in Eclipse with ADT</a> or <a
href="../../../guide/developing/other-ide.html#libraryProject">Developing in
Other IDEs</a>, depending on your environment.</p>

<img alt="Screenshot of the main application" src="../images/TicTacToeMain.png" />
<img alt="Screenshot of an Activity declared in a library project" src="../images/TicTacToeLib.png" />