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 <meta name="doc-family" content="apps">
 <h1>Build Apps with Sencha Ext JS</h1>
 
 <p>
 The goal of this doc is to get you started
 on building Chrome Apps with the
 <a href="http://www.sencha.com/products/extjs">Sencha Ext JS</a> framework.
 To achieve this goal,
 we will dive into a media player app built by Sencha.
 The <a href="https://github.com/GoogleChrome/sencha-video-player-app">source code</a>
 and <a href="http://senchaprosvcs.github.com/GooglePlayer/docs/output/#!/api">API Documentation</a> are available on GitHub.
 </p>
 
 <p>
 This app discovers a user's available media servers,
 including media devices connected to the pc and
 software that manages media over the network. 
 Users can browse media, play over the network,
 or save offline.
 </p>
 
 <p>Here are the key things you must do
 to build a media player app using Sencha Ext JS:
 </p>
 
 <ul>
   <li>Create manifest, <code>manifest.json</code>.</li>
-  <li>Create <a href="app_lifecycle.html#eventpage">event page</a>,
+  <li>Create <a href="app_lifecycle#eventpage">event page</a>,
     <code>background.js</code>.</li>
-  <li><a href="app_external.html#sandboxing">Sandbox</a> app's logic.</li>
+  <li><a href="app_external#sandboxing">Sandbox</a> app's logic.</li>
   <li>Communicate between Chrome App and sandboxed files.</li>
   <li>Discover media servers.</li>
   <li>Explore and play media.</li>
   <li>Save media offline.</li>
 </ul>
 
 <h2 id="first">Create manifest</h2>
 
 <p>
 All Chrome Apps require a
-<a href="manifest.html">manifest file</a>
+<a href="manifest">manifest file</a>
 which contains the information Chrome needs to launch apps.
 As indicated in the manifest,
 the media player app is "offline_enabled";
 media assets can be saved locally,
 accessed and played regardless of connectivity.
 </p>
 
 <p>
 The "sandbox" field is used
 to sandbox the app's main logic in a unique origin.
 All sandboxed content is exempt from the Chrome App
-<a href="contentSecurityPolicy.html">Content Security Policy</a>,
+<a href="contentSecurityPolicy">Content Security Policy</a>,
 but cannot directly access the Chrome App APIs. 
 The manifest also includes the "socket" permission;
-the media player app uses the <a href="socket.html">socket API</a>
+the media player app uses the <a href="socket">socket API</a>
 to connect to a media server over the network.
 </p>
 
 <pre data-filename="manifest.json">
 {
     "name": "Video Player",
     "description": "Features network media discovery and playlist management",
     "version": "1.0.0",
     "manifest_version": 2,
     "offline_enabled": true,
@@ skipping 43 matching lines @@
     chrome.app.window.create('index.html', opt, function (win) {
         win.launchData = launchData;
     });
 
 });
 </pre>
 
 <h2 id="three">Sandbox app's logic</h2>
 
 <p>Chrome Apps run in a controlled environment
-that enforces a strict <a href="contentSecurityPolicy.html">Content Security Policy (CSP)</a>.
+that enforces a strict <a href="contentSecurityPolicy">Content Security Policy (CSP)</a>.
 The media player app needs some higher privileges to render the Ext JS components.
 To comply with CSP and execute the app logic,
 the app's main page, <code>index.html</code>, creates an iframe
 that acts as a sandbox environment:
 
 <pre data-filename="index.html">
 &lt;iframe id="sandbox-frame" sandbox="allow-scripts" src="sandbox.html">&lt;/iframe>
 </pre>
 
 <p>The iframe points to <a href="https://github.com/GoogleChrome/sencha-video-player-app/blob/master/sandbox.html">sandbox.html</a> which includes the files required for the Ext JS application:
@@ skipping 115 matching lines @@
 At a high level, the discovery workflow is initiated
 by a user action to search for available media servers.
 The <a href="https://github.com/GoogleChrome/sencha-video-player-app/blob/master/app/controller/MediaServers.js">MediaServer controller</a>
 posts a message to <code>index.js</code>;
 <code>index.js</code> listens for this message and when received,
 calls <a href="https://github.com/GoogleChrome/sencha-video-player-app/blob/master/lib/Upnp.js">Upnp.js</a>.
 </p>
 
 <p>
 The <code>Upnp library</code> uses the Chrome App
-<a href="app_network.html">socket API</a>
+<a href="app_network">socket API</a>
 to connect the media player app with any discovered media servers
 and receive media data from the media server.
 <code>Upnp.js</code> also uses
 <a href="https://github.com/GoogleChrome/sencha-video-player-app/blob/master/lib/soapclient.js">soapclient.js</a>
 to parse the media server data.
 The remainder of this section describes this workflow in more detail.
 </p>
 
 <h3 id="post">Post message</h3>
 
@@ skipping 302 matching lines @@
     }
 );
 </pre>
 
 <p>
 When the download process is finished,
 <code>MediaExplorer</code> updates the media file list and the media player tree panel.
 </p>
 
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