| <!DOCTYPE html><!-- This page is a placeholder for generated extensions api doc. Note: |
| 1) The <head> information in this page is significant, should be uniform |
| across api docs and should be edited only with knowledge of the |
| templating mechanism. |
| 3) All <body>.innerHTML is genereated as an rendering step. If viewed in a |
| browser, it will be re-generated from the template, json schema and |
| authored overview content. |
| 4) The <body>.innerHTML is also generated by an offline step so that this |
| page may easily be indexed by search engines. |
| --><html xmlns="http://www.w3.org/1999/xhtml"><head> |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> |
| <link href="css/ApiRefStyles.css" rel="stylesheet" type="text/css"> |
| <link href="css/print.css" rel="stylesheet" type="text/css" media="print"> |
| <script type="text/javascript" src="../../../third_party/jstemplate/jstemplate_compiled.js"> |
| </script> |
| <script type="text/javascript" src="js/api_page_generator.js"></script> |
| <script type="text/javascript" src="js/bootstrap.js"></script> |
| <script type="text/javascript" src="js/sidebar.js"></script> |
| <title>Frequently Asked Questions - Google Chrome Extensions - Google Code</title></head> |
| <body> <div id="gc-container" class="labs"> |
| <div id="devModeWarning"> |
| You are viewing extension docs in chrome via the 'file:' scheme: are you expecting to see local changes when you refresh? You'll need run chrome with --allow-file-access-from-files. |
| </div> |
| <!-- SUBTEMPLATES: DO NOT MOVE FROM THIS LOCATION --> |
| <!-- In particular, sub-templates that recurse, must be used by allowing |
| jstemplate to make a copy of the template in this section which |
| are not operated on by way of the jsskip="true" --> |
| <div style="display:none"> |
| |
| <!-- VALUE --> |
| <div id="valueTemplate"> |
| <dt> |
| <var>paramName</var> |
| <em> |
| |
| <!-- TYPE --> |
| <div style="display:inline"> |
| ( |
| <span class="optional">optional</span> |
| <span class="enum">enumerated</span> |
| <span id="typeTemplate"> |
| <span> |
| <a> Type</a> |
| </span> |
| <span> |
| <span> |
| array of <span><span></span></span> |
| </span> |
| <span>paramType</span> |
| <span></span> |
| </span> |
| </span> |
| ) |
| </div> |
| |
| </em> |
| </dt> |
| <dd class="todo"> |
| Undocumented. |
| </dd> |
| <dd> |
| Description of this parameter from the json schema. |
| </dd> |
| <dd> |
| This parameter was added in version |
| <b><span></span></b>. |
| You must omit this parameter in earlier versions, |
| and you may omit it in any version. If you require this |
| parameter, the manifest key |
| <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a> |
| can ensure that your extension won't be run in an earlier browser version. |
| </dd> |
| |
| <!-- OBJECT PROPERTIES --> |
| <dd> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| </dd> |
| |
| <!-- OBJECT METHODS --> |
| <dd> |
| <div></div> |
| </dd> |
| |
| <!-- OBJECT EVENT FIELDS --> |
| <dd> |
| <div></div> |
| </dd> |
| |
| <!-- FUNCTION PARAMETERS --> |
| <dd> |
| <div></div> |
| </dd> |
| |
| </div> <!-- /VALUE --> |
| |
| <div id="functionParametersTemplate"> |
| <h5>Parameters</h5> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| </div> |
| </div> <!-- /SUBTEMPLATES --> |
| |
| <a id="top"></a> |
| <div id="skipto"> |
| <a href="#gc-pagecontent">Skip to page content</a> |
| <a href="#gc-toc">Skip to main navigation</a> |
| </div> |
| <!-- API HEADER --> |
| <table id="header" width="100%" cellspacing="0" border="0"> |
| <tbody><tr> |
| <td valign="middle"><a href="http://code.google.com/"><img src="images/code_labs_logo.gif" height="43" width="161" alt="Google Code Labs" style="border:0; margin:0;"></a></td> |
| <td valign="middle" width="100%" style="padding-left:0.6em;"> |
| <form action="http://www.google.com/cse" id="cse" style="margin-top:0.5em"> |
| <div id="gsc-search-box"> |
| <input type="hidden" name="cx" value="002967670403910741006:61_cvzfqtno"> |
| <input type="hidden" name="ie" value="UTF-8"> |
| <input type="text" name="q" value="" size="55"> |
| <input class="gsc-search-button" type="submit" name="sa" value="Search"> |
| <br> |
| <span class="greytext">e.g. "page action" or "tabs"</span> |
| </div> |
| </form> |
| |
| <script type="text/javascript" src="http://www.google.com/jsapi"></script> |
| <script type="text/javascript">google.load("elements", "1", {packages: "transliteration"});</script> |
| <script type="text/javascript" src="http://www.google.com/coop/cse/t13n?form=cse&t13n_langs=en"></script> |
| <script type="text/javascript" src="http://www.google.com/coop/cse/brand?form=cse&lang=en"></script> |
| </td> |
| </tr> |
| </tbody></table> |
| |
| <div id="codesiteContent" class=""> |
| |
| <a id="gc-topnav-anchor"></a> |
| <div id="gc-topnav"> |
| <h1>Google Chrome Extensions (<a href="http://code.google.com/labs/">Labs</a>)</h1> |
| <ul id="home" class="gc-topnav-tabs"> |
| <li id="home_link"> |
| <a href="index.html" title="Google Chrome Extensions home page">Home</a> |
| </li> |
| <li id="docs_link"> |
| <a href="docs.html" title="Official Google Chrome Extensions documentation">Docs</a> |
| </li> |
| <li id="faq_link"> |
| <a href="faq.html" title="Answers to frequently asked questions about Google Chrome Extensions">FAQ</a> |
| </li> |
| <li id="samples_link"> |
| <a href="samples.html" title="Sample extensions (with source code)">Samples</a> |
| </li> |
| <li id="group_link"> |
| <a href="http://groups.google.com/a/chromium.org/group/chromium-extensions" title="Google Chrome Extensions developer forum">Group</a> |
| </li> |
| </ul> |
| </div> <!-- end gc-topnav --> |
| |
| <div class="g-section g-tpl-170"> |
| <!-- SIDENAV --> |
| <div class="g-unit g-first" id="gc-toc"> |
| <ul> |
| <li><a href="getstarted.html">Getting Started</a></li> |
| <li><a href="overview.html">Overview</a></li> |
| <li><a href="whats_new.html">What's New?</a></li> |
| <li><h2><a href="devguide.html">Developer's Guide</a></h2> |
| <ul> |
| <li>Browser UI |
| <ul> |
| <li><a href="browserAction.html">Browser Actions</a></li> |
| <li><a href="contextMenus.html">Context Menus</a></li> |
| <li><a href="notifications.html">Desktop Notifications</a></li> |
| <li><a href="omnibox.html">Omnibox</a></li> |
| <li><a href="options.html">Options Pages</a></li> |
| <li><a href="override.html">Override Pages</a></li> |
| <li><a href="pageAction.html">Page Actions</a></li> |
| </ul> |
| </li> |
| <li>Browser Interaction |
| <ul> |
| <li><a href="bookmarks.html">Bookmarks</a></li> |
| <li><a href="cookies.html">Cookies</a></li> |
| <li><a href="events.html">Events</a></li> |
| <li><a href="history.html">History</a></li> |
| <li><a href="management.html">Management</a></li> |
| <li><a href="tabs.html">Tabs</a></li> |
| <li><a href="windows.html">Windows</a></li> |
| </ul> |
| </li> |
| <li>Implementation |
| <ul> |
| <li><a href="a11y.html">Accessibility</a></li> |
| <li><a href="background_pages.html">Background Pages</a></li> |
| <li><a href="content_scripts.html">Content Scripts</a></li> |
| <li><a href="xhr.html">Cross-Origin XHR</a></li> |
| <li><a href="idle.html">Idle</a></li> |
| <li><a href="i18n.html">Internationalization</a></li> |
| <li><a href="messaging.html">Message Passing</a></li> |
| <li><a href="npapi.html">NPAPI Plugins</a></li> |
| </ul> |
| </li> |
| <li>Finishing |
| <ul> |
| <li><a href="hosting.html">Hosting</a></li> |
| <li><a href="external_extensions.html">Other Deployment Options</a></li> |
| </ul> |
| </li> |
| </ul> |
| </li> |
| <li><h2><a href="apps.html">Packaged Apps</a></h2></li> |
| <li><h2><a href="tutorials.html">Tutorials</a></h2> |
| <ul> |
| <li><a href="tut_debugging.html">Debugging</a></li> |
| <li><a href="tut_analytics.html">Google Analytics</a></li> |
| <li><a href="tut_oauth.html">OAuth</a></li> |
| </ul> |
| </li> |
| <li><h2>Reference</h2> |
| <ul> |
| <li>Formats |
| <ul> |
| <li><a href="manifest.html">Manifest Files</a></li> |
| <li><a href="match_patterns.html">Match Patterns</a></li> |
| </ul> |
| </li> |
| <li><a href="permission_warnings.html">Permission Warnings</a></li> |
| <li><a href="api_index.html">chrome.* APIs</a></li> |
| <li><a href="api_other.html">Other APIs</a></li> |
| </ul> |
| </li> |
| <li><h2><a href="samples.html">Samples</a></h2></li> |
| <div class="line"> </div> |
| <li><h2>More</h2> |
| <ul> |
| <li><a href="http://code.google.com/chrome/webstore/docs/index.html">Chrome Web Store</a></li> |
| <li><a href="http://code.google.com/chrome/apps/docs/developers_guide.html">Hosted Apps</a></li> |
| <li><a href="themes.html">Themes</a></li> |
| </ul> |
| </li> |
| </ul> |
| </div> |
| <script> |
| initToggles(); |
| </script> |
| |
| <div class="g-unit" id="gc-pagecontent"> |
| <div id="pageTitle"> |
| <h1 class="page_title">Frequently Asked Questions</h1> |
| </div> |
| <!-- TABLE OF CONTENTS --> |
| <div id="toc" style="display: none; "> |
| <h2>Contents</h2> |
| <ol> |
| <li> |
| <a>h2Name</a> |
| <ol> |
| <li> |
| <a>h3Name</a> |
| </li> |
| </ol> |
| </li> |
| <li> |
| <a href="#apiReference">API reference</a> |
| <ol> |
| <li> |
| <a href="#properties">Properties</a> |
| <ol> |
| <li> |
| <a href="#property-anchor">propertyName</a> |
| </li> |
| </ol> |
| </li> |
| <li> |
| <a>Methods</a> |
| <ol> |
| <li> |
| <a href="#method-anchor">methodName</a> |
| </li> |
| </ol> |
| </li> |
| <li> |
| <a>Events</a> |
| <ol> |
| <li> |
| <a href="#event-anchor">eventName</a> |
| </li> |
| </ol> |
| </li> |
| <li> |
| <a href="#types">Types</a> |
| <ol> |
| <li> |
| <a href="#id-anchor">id</a> |
| </li> |
| </ol> |
| </li> |
| </ol> |
| </li> |
| </ol> |
| </div> |
| <!-- /TABLE OF CONTENTS --> |
| |
| <!-- Standard content lead-in for experimental API pages --> |
| <p id="classSummary" style="display: none; "> |
| For information on how to use experimental APIs, see the <a href="experimental.html">chrome.experimental.* APIs</a> page. |
| </p> |
| |
| <!-- STATIC CONTENT PLACEHOLDER --> |
| <div id="static"><div id="pageData-name" class="pageData">Frequently Asked Questions</div> |
| |
| |
| <!-- <div id="pageData-showTOC" class="pageData">true</div> --> |
| |
| <p> |
| If you don't find an answer to your question here, |
| try the |
| <a href="http://code.google.com/chrome/webstore/faq.html">Chrome Web Store FAQ</a>, the |
| <a href="http://groups.google.com/a/chromium.org/group/chromium-extensions">group</a>, or the |
| <a href="http://www.google.com/support/chrome/bin/answer.py?answer=113909">gallery help</a>. |
| <!-- PENDING: add a link to store help --> |
| </p> |
| |
| <div id="faq-TOC"> |
| <h4>General</h4> |
| <ul> |
| <li><a href="#faq-gen-01">What are Google Chrome Extensions?</a></li> |
| <li><a href="#faq-dev-01">How can I set up Chrome for extension development?</a></li> |
| <li><a href="#faq-gen-02">What technologies are used to write extensions for Chrome?</a></li> |
| <li><a href="#faq-gen-03">Are extensions fetched from the web every time the browser is loaded?</a></li> |
| <li><a href="#faq-dev-14">How do I determine which version of Chrome is deployed to which channel?</a></li> |
| </ul> |
| <h4>Capabilities</h4> |
| <ul> |
| <li><a href="#faq-dev-02">Can extensions make cross-domain Ajax requests?</a></li> |
| <li><a href="#faq-dev-03">Can extensions use 3rd party web services?</a></li> |
| <li><a href="#faq-dev-07">Can extensions encode/decode JSON data?</a></li> |
| <li><a href="#faq-dev-08">Can extensions store data locally?</a></li> |
| <li><a href="#faq-dev-04">Can extensions use OAuth?</a></li> |
| <li><a href="#faq-dev-06">Can extensions load DLLs?</a></li> |
| <li><a href="#faq-dev-05">Can extensions create UI outside of the rendered web page?</a></li> |
| <li><a href="#faq-interact-chrome">Can extensions listen to clicks on Chrome tabs and navigation buttons?</a> |
| </li><li><a href="#faq-dev-11">Can two extensions communicate with each other?</a></li> |
| <li><a href="#faq-dev-13">Can extensions use Google Analytics?</a></li> |
| <li><a href="#faq-dev-15">Can extensions modify chrome:// URLs?</a></li> |
| <li><a href="#faq-open-popups">Can extensions open browser/page action popups without user interaction?</a></li> |
| <li><a href="#faq-persist-popups">Can extensions keep popups open after the user clicks away from them?</a></li> |
| <li><a href="#faq-lifecycle-events">Can extensions be notified when they are installed/uninstalled?</a></li> |
| </ul> |
| <h4>Development</h4> |
| <ul> |
| <li><a href="#faq-building-ui">How do I build a UI for my extension?</a> |
| </li><li><a href="#faq-dev-09">How much data can I store in localStorage?</a></li> |
| <li><a href="#faq-dev-10">How do I create an options menu for my application?</a></li> |
| <li><a href="#faq-dev-12">What debugging tools are available to extension developers?</a></li> |
| <li><a href="#faq-dev-16">Why do wildcard matches not work for top level domains (TLDs)?</a></li> |
| <li><a href="#faq-management">Why does the management API not fire events when my extension is installed/uninstalled?</a></li> |
| <li><a href="#faq-firstrun">How can an extension determine whether it is running for the first time?</a></li> |
| </ul> |
| <h4>Features and bugs</h4> |
| <ul> |
| <li><a href="#faq-fea-01">I think I've found a bug! How do I make sure it gets fixed?</a></li> |
| <li><a href="#faq-fea-02">I have a feature request! How can I report it?</a></li> |
| </ul> |
| </div> |
| |
| <h2>General</h2> |
| |
| <h3 id="faq-gen-01">What are Google Chrome Extensions?</h3> |
| <p> |
| Google Chrome Extensions are applications that run inside the |
| Chrome browser and provide additional functionality, integration with third |
| party websites or services, and customized browsing experiences. |
| </p> |
| |
| <h3 id="faq-dev-01">How can I set up Chrome for extension development?</h3> |
| <p> |
| As long as you are using a version of Chrome that supports |
| extensions, you already have everything you need to start writing an |
| extension of your own. |
| You can start by turning on Developer mode. |
| </p> |
| |
| <p> |
| Click the wrench icon |
| <img src="images/toolsmenu.gif" height="29" width="29" alt="" class="nomargin"> |
| and select <b>Extensions</b> from the <b>Tools</b> menu. |
| If there's a "+" next to "Developer mode", |
| click the "+" so it turns into a "-". |
| Now you can reload extensions, |
| load an unpacked directory of files as if it were a packaged extension, |
| and more. For a complete tutorial, see |
| <a href="http://code.google.com/chrome/extensions/getstarted.html">Getting Started</a>. |
| </p> |
| |
| <h3 id="faq-gen-02">What technologies are used to write extensions for Chrome?</h3> |
| <p> |
| Extensions are written using the same standard web |
| technologies that developers use to create websites. HTML is used as a |
| content markup language, CSS is used for styling, and JavaScript for |
| scripting. Because Chrome supports HTML5 and CSS3, developers can |
| use the latest open web technologies such as canvas and CSS animations in |
| their extensions. Extensions also have access to several |
| <a href="http://code.google.com/chrome/extensions/api_other.html">JavaScript APIs</a> |
| that help perform functions like JSON encoding and interacting with the |
| browser. |
| </p> |
| |
| |
| <h3 id="faq-gen-03">Are extensions fetched from the web every time the browser is loaded?</h3> |
| <p> |
| Extensions are downloaded by the Chrome browser upon install, and |
| are subsequently run off of the local disk in order to speed up |
| performance. However, if a new version of the extension is pushed online, |
| it will be automatically downloaded in the background to any users who |
| have the extension installed. Extensions may also make requests for remote |
| content at any time, in order to interact with a web service or pull new |
| content from the web. |
| </p> |
| |
| <h3 id="faq-dev-14">How do I determine which version of Chrome is deployed to which channel?</h3> |
| <p> |
| To determine which version of Chrome is currently available on each |
| of the different platforms, visit |
| <a href="http://omahaproxy.appspot.com">omahaproxy.appspot.com</a>. On that |
| site you will see data in a format similar to: |
| </p> |
| |
| <pre>cf,dev,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| cf,beta,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| cf,stable,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| linux,dev,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| linux,beta,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| linux,stable,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| mac,dev,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| mac,beta,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| mac,stable,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| win,canary,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| win,dev,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| win,beta,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| win,stable,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| cros,dev,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,##### |
| cros,beta,#.#.###.#,#.#.###.#,mm/dd/yy,mm/dd/yy,#####,#####,#####</pre> |
| |
| <p> |
| Each line represents information about a different platform and channel |
| combination. The |
| listed platforms are <code>cf</code> (Google Chrome Frame), |
| <code>linux</code>, <code>mac</code>, <code>win</code>, and |
| <code>cros</code> (Google Chrome OS). The listed |
| channels are <code>canary</code>, <code>dev</code>, <code>beta</code>, |
| and <code>stable</code>. |
| The two four-part numbers after the channel represent the current and previous |
| versions of Chrome deployed to that platform-channel |
| combination. The rest of the information is metadata about when the releases |
| were first pushed, as well as revision numbers associated with each build. |
| </p> |
| |
| |
| <h2>Capabilities</h2> |
| |
| <h3 id="faq-dev-02">Can extensions make cross-domain Ajax requests?</h3> |
| <p> |
| Yes. Extensions can make cross-domain requests. See |
| <a href="http://code.google.com/chrome/extensions/xhr.html">this page</a> |
| for more information. |
| </p> |
| |
| <h3 id="faq-dev-03">Can extensions use 3rd party web services?</h3> |
| <p> |
| Yes. Extensions are capable of making cross-domain Ajax |
| requests, so they can call remote APIs directly. APIs that provide data |
| in JSON format are particularly easy to use. |
| </p> |
| |
| <h3 id="faq-dev-07">Can extensions encode/decode JSON data?</h3> |
| <p> |
| Yes, because V8 (Chrome's JavaScript engine) supports |
| JSON.stringify and JSON.parse natively, you may use these functions in your |
| extensions |
| <a href="http://json.org/js.html">as described here</a> without including |
| any additional JSON libraries in your code. |
| </p> |
| |
| <h3 id="faq-dev-08">Can extensions store data locally?</h3> |
| <p> |
| Yes, extensions can use <a href="http://dev.w3.org/html5/webstorage/">localStorage</a> |
| to store string data permanently. Using Chrome's built-in JSON |
| functions, you can store complex data structures in localStorage. For |
| extensions that need to execute SQL queries on their stored data, |
| Chrome implements |
| <a href="http://dev.w3.org/html5/webdatabase/">client side SQL databases</a>, |
| which may be used as well. |
| </p> |
| |
| <h3 id="faq-dev-04">Can extensions use OAuth?</h3> |
| <p> |
| Yes, there are extensions that use OAuth to access remote data |
| APIs. Most developers find it convenient to use a |
| <a href="http://unitedheroes.net/OAuthSimple/js/OAuthSimple.js">JavaScript OAuth library</a> |
| in order to simplify the process of signing OAuth requests. |
| </p> |
| |
| <h3 id="faq-dev-06">Can extensions load DLLs?</h3> |
| <p> |
| Yes, using the <a href="npapi.html">NPAPI interface</a>. |
| Because of the possibility for abuse, though, we will review your extension |
| before hosting it in the Google Chrome Extensions Gallery |
| or Chrome Web Store. |
| </p> |
| |
| <h3 id="faq-dev-05">Can extensions create UI outside of the rendered web page?</h3> |
| <p> |
| Yes, your extension may add buttons to the Chrome browser's user interface. |
| See <a href="browserAction.html">browser actions</a> and |
| <a href="pageAction.html">page actions</a> for more information. |
| </p> |
| <p> |
| An extension may also create popup notifications, which exist outside of the |
| browser window. See the <a href="notifications.html">desktop |
| notifications</a> documentation for more details. |
| </p> |
| |
| <h3 id="faq-interact-chrome">Can extensions listen to clicks on Chrome tabs and |
| navigation buttons?</h3> |
| <p> |
| No. Extensions are limited to listening to the events described in the <a href="api_index.html">API documentation</a>. |
| </p> |
| |
| <h3 id="faq-dev-11">Can two extensions communicate with each other?</h3> |
| <p> |
| Yes, extensions may pass messages to other extensions. See the |
| <a href="messaging.html#external">message passing documentation</a> |
| for more information. |
| </p> |
| |
| <h3 id="faq-dev-13">Can extensions use Google Analytics?</h3> |
| <p> |
| Yes, since extensions are built just like websites, they can use |
| <a href="http://www.google.com/analytics/">Google Analytics</a> to track |
| usage. However, we strongly advise you to modify the tracking code to pull |
| an HTTPS version of the Google Analytics library. See |
| <a href="tut_analytics.html">this tutorial</a> for more information on doing |
| this. |
| </p> |
| |
| <h3 id="faq-dev-15">Can extensions modify chrome:// URLs?</h3> |
| <p> |
| No. The extensions APIs have been designed to minimize backwards |
| compatibility issues that can arise when new versions of the browser are |
| pushed. Allowing content scripts on <code>chrome://</code> |
| URLs would mean that developers would begin to rely on the DOM, CSS, and |
| JavaScript of these pages to stay the same. In the best case, these pages |
| could not be updated as quickly as they are being updated right now. |
| In the worst case, it could mean that an update to one |
| of these pages could cause an extension to break, causing key parts of the |
| browser to stop working for users of that extension. |
| </p> |
| |
| <p> |
| The reason that <a href="override.html">replacing the content</a> |
| hosted at these URLs entirely is |
| allowed is because it forces an extension developer to implement all of the |
| functionality they want without depending on the browser's internal implementation |
| to stay the same. |
| </p> |
| |
| <h3 id="faq-open-popups">Can extensions open browser/page action popups without |
| user interaction?</h3> |
| <p> |
| No, popups can only be opened if the user clicks on the corresponding page or |
| browser action. An extension cannot open its popup programatically. |
| </p> |
| |
| <h3 id="faq-persist-popups">Can extensions keep popups open after the user |
| clicks away from them?</h3> |
| <p> |
| No, popups automatically close when the user focuses on some portion of the |
| browser outside of the popup. There is no way to keep the popup open after |
| the user has clicked away. |
| </p> |
| |
| <h3 id="faq-lifecycle-events">Can extensions be notified when they are |
| installed/uninstalled?</h3> |
| <p> |
| No, there are no events an extension can listen to in order to determine |
| whether it has been installed or uninstalled. However, an extension can |
| determine when it has been run for the first time. See <a href="#faq-firstrun">this FAQ entry</a> for information. |
| </p> |
| |
| |
| <h2>Development</h2> |
| |
| |
| <h3 id="faq-building-ui">How do I build a UI for my extension?</h3> |
| <p> |
| Extensions use HTML and CSS to define their user interfaces, so you can use |
| standard form controls to build your UI, or style the interface with CSS, |
| as you would a web page. Additionally, extensions can add |
| <a href="#faq-dev-05">some limited UI elements to Chrome itself.</a> |
| </p> |
| |
| <h3 id="faq-dev-09">How much data can I store in localStorage?</h3> |
| <p> |
| Extensions can store up to 5MB of data in localStorage. |
| </p> |
| |
| <h3 id="faq-dev-10">How do I create an options menu for my application?</h3> |
| <p> |
| You can let users set options for your extension by creating an |
| <a href="http://code.google.com/chrome/extensions/trunk/options.html">options page</a>, |
| which is a simple HTML page that will be loaded when a user clicks the |
| "options" button for your extension. This page can read and write settings |
| to localStorage, or even send options to a web server so that they can be |
| persisted across browsers. |
| </p> |
| |
| <h3 id="faq-dev-12">What debugging tools are available to extension developers?</h3> |
| <p> |
| Chrome's built-in developer tools can be used to debug extensions |
| as well as web pages. See this |
| <a href="http://code.google.com/chrome/extensions/tut_debugging.html ">tutorial on debugging extensions</a> |
| for more information. |
| </p> |
| |
| <h3 id="faq-dev-16">Why do wildcard matches not work for top level domains |
| (TLDs)?</h3> |
| <p> |
| You cannot use wildcard match patterns like <code>http://google.*/*</code> |
| to match TLDs (like <code>http://google.es</code> and |
| <code>http://google.fr</code>) due to the |
| complexity of actually restricting such a match to only the desired domains. |
| </p> |
| <p> |
| For the example of <code>http://google.*/*</code>, the Google domains would |
| be matched, but so would <code>http://google.someotherdomain.com</code>. |
| Additionally, many sites do not own all of the TLDs for their |
| domain. For an example, assume you want to use |
| <code>http://example.*/*</code> to match <code>http://example.com</code> and |
| <code>http://example.es</code>, but <code>http://example.net</code> is a |
| hostile site. If your extension has a bug, the hostile site could potentially |
| attack your extension in order to get access to your extension's increased |
| privileges. |
| </p> |
| <p> |
| You should explicitly enumerate the TLDs that you wish to run |
| your extension on. |
| </p> |
| |
| <h3 id="faq-management">Why does the management API not fire events when my |
| extension is installed/uninstalled?</h3> |
| <p> |
| The <a href="management.html">management API</a> was intended to help create |
| new tab page replacement extensions. It was not intended to fire |
| install/uninstall events for the current extension. |
| </p> |
| |
| <h3 id="faq-firstrun">How can an extension determine whether it is running for |
| the first time?</h3> |
| <p> |
| An extension can check to see whether it is running for the first time by |
| checking for the presence of a value in localStorage, and writing the value if |
| it does not exist. For example: |
| </p> |
| |
| <pre>var firstRun = (localStorage['firstRun'] == 'true'); |
| if (!firstRun) { |
| localStorage['firstRun'] = 'true'; |
| }</pre> |
| |
| <p> |
| Note that this check should be run in a background page, not a content script. |
| </p> |
| |
| |
| <h2>Features and bugs</h2> |
| |
| |
| <h3 id="faq-fea-01">I think I've found a bug! How do I make sure it gets |
| fixed?</h3> |
| <p> |
| While developing an extension, you may find behavior that does not |
| match the extensions documentation and may be the result of a bug in |
| Chrome. The best thing to do is to make sure an appropriate issue |
| report is filed, and the Chromium team has enough information to reproduce |
| the behavior. |
| </p> |
| |
| <p>The steps you should follow to ensure this are:</p> |
| |
| <ol> |
| <li> |
| Come up with a <em>minimal</em> test extension that demonstrates the issue |
| you wish to report. This extension should have as little code as possible |
| to demonstrate the bug—generally this should be 100 lines of |
| code or less. Many times, developers find that they cannot reproduce their |
| issues this way, which is a good indicator that the bug is in their own |
| code. |
| </li> |
| <li> |
| Search the issue tracker at |
| <a href="http://www.crbug.com">http://www.crbug.com</a> to see whether |
| someone has reported a similar issue. Most issues related to |
| extensions are filed under <strong>Feature=Extensions</strong>, so to |
| look for an extension bug related to the |
| chrome.tabs.executeScript function (for example), search for |
| "<code>Feature=Extensions Type=Bug chrome.tabs.executeScript</code>", |
| which will give you |
| <a href="http://code.google.com/p/chromium/issues/list?can=2&q=Feature%3DExtensions+Type%3DBug+chrome.tabs.executeScript&colspec=ID+Stars+Pri+Area+Feature+Type+Status+Summary+Modified+Owner+Mstone+OS&x=mstone&y=area&cells=tiles"> |
| this list of results</a>. |
| </li> |
| <li> |
| If you find a bug that describes your issue, click the star icon to be |
| notified when the bug receives an update. <em>Do not respond to the |
| bug to say "me too" or ask "when will this be fixed?"</em>; such updates |
| can cause hundreds of emails to be sent. Add a comment only if you have |
| information (such as a better test case or a suggested fix) that is likely |
| to be helpful. |
| </li> |
| <li> |
| If you found no appropriate bug to star, file a new issue report at |
| <a href="http://new.crbug.com">http://new.crbug.com</a>. Be as explicit |
| as possible when filling out this form: choose a descriptive title, |
| explain the steps to reproduce the bug, and describe the expected and |
| actual behavior. Attach your test example to the report and add |
| screenshots if appropriate. The easier your report makes it for others |
| to reproduce your issue, the greater chance that your bug will be fixed |
| promptly. |
| </li> |
| <li> |
| Wait for the bug to be updated. Most new bugs are triaged within a week, |
| although it can sometimes take longer for an update. <em>Do not reply |
| to the bug to ask when the issue will be fixed.</em> If your bug has not |
| been modified after two weeks, please post a message to the |
| <a href="http://groups.google.com/a/chromium.org/group/chromium-extensions/topics"> |
| discussion group</a> with a link back to your bug. |
| </li> |
| <li> |
| If you originally reported your bug on the discussion group and were |
| directed to this FAQ entry, reply to your original thread with a link |
| to the bug you starred or reported. This will make it easier for others |
| experiencing the same issue to find the correct bug. |
| </li> |
| </ol> |
| |
| <h3 id="faq-fea-02">I have a feature request! How can I report it?</h3> |
| |
| <p>If you identify a feature (especially if it's related to an experimental |
| API) that could be added to improve the extension development experience, |
| make sure an appropriate request is filed in the issue tracker.</p> |
| |
| <p>The steps you should follow to ensure this are:</p> |
| |
| <ol> |
| <li> |
| Search the issue tracker at |
| <a href="http://www.crbug.com">http://www.crbug.com</a> to see whether |
| someone has requested a similar feature. Most requests related to |
| extensions are filed under <strong>Feature=Extensions</strong>, so to |
| look for an extension feature request related to keyboard shortcuts |
| (for example), search |
| for "<code>Feature=Extensions Type=Feature shortcuts</code>", |
| which will give you |
| <a href="http://code.google.com/p/chromium/issues/list?can=2&q=Feature%3DExtensions+Type%3DFeature+shortcuts&colspec=ID+Stars+Pri+Area+Feature+Type+Status+Summary+Modified+Owner+Mstone+OS&x=mstone&y=area&cells=tiles"> |
| this list of results</a>. |
| </li> |
| <li> |
| If you find a ticket that matches your request, click the star icon to be |
| notified when the bug receives an update. <em>Do not respond to the |
| bug to say "me too" or ask "when will this be implemented?"</em>; such |
| updates can cause hundreds of emails to be sent. |
| </li> |
| <li> |
| If you found no appropriate ticket to star, file a new request at |
| <a href="http://new.crbug.com">http://new.crbug.com</a>. Be as detailed |
| as possible when filling out this form: choose a descriptive title |
| and explain exactly what feature you would like and how you plan to use it. |
| </li> |
| <li> |
| Wait for the ticket to be updated. Most new requests are triaged within a |
| week, although it can sometimes take longer for an update. <em>Do not reply |
| to the ticket to ask when the feature will be added.</em> If your |
| ticket has not been modified after two weeks, please post a message to the |
| <a href="http://groups.google.com/a/chromium.org/group/chromium-extensions/topics"> |
| discussion group</a> with a link back to your request. |
| </li> |
| <li> |
| If you originally reported your request on the discussion group and were |
| directed to this FAQ entry, reply to your original thread with a link |
| to the ticket you starred or opened. This will make it easier for others |
| with the same request to find the correct ticket. |
| </li> |
| </ol> |
| |
| </div> |
| |
| <!-- API PAGE --> |
| <div class="apiPage" style="display: none; "> |
| <a name="apiReference"></a> |
| <h2>API reference: chrome.apiname </h2> |
| |
| <!-- PROPERTIES --> |
| <div class="apiGroup"> |
| <a name="properties"></a> |
| <h3 id="properties">Properties</h3> |
| |
| <div> |
| <a></a> |
| <h4>getLastError</h4> |
| <div class="summary"> |
| <!-- Note: intentionally longer 80 columns --> |
| <span>chrome.extension</span><span>lastError</span> |
| </div> |
| <div> |
| </div> |
| </div> |
| |
| </div> <!-- /apiGroup --> |
| |
| <!-- METHODS --> |
| <div id="methodsTemplate" class="apiGroup"> |
| <a></a> |
| <h3>Methods</h3> |
| |
| <!-- iterates over all functions --> |
| <div class="apiItem"> |
| <a></a> <!-- method-anchor --> |
| <h4>method name</h4> |
| |
| <div class="summary"><span>void</span> |
| <!-- Note: intentionally longer 80 columns --> |
| <span>chrome.module.methodName</span>(<span><span>, </span><span></span> |
| <var><span></span></var></span>)</div> |
| |
| <div class="description"> |
| <p class="todo">Undocumented.</p> |
| <p> |
| A description from the json schema def of the function goes here. |
| </p> |
| |
| <!-- PARAMETERS --> |
| <h4>Parameters</h4> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| |
| <!-- RETURNS --> |
| <h4>Returns</h4> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| |
| <!-- CALLBACK --> |
| <div> |
| <div> |
| <h4>Callback function</h4> |
| <p> |
| The callback <em>parameter</em> should specify a function |
| that looks like this: |
| </p> |
| <p> |
| If you specify the <em>callback</em> parameter, it should |
| specify a function that looks like this: |
| </p> |
| |
| <!-- Note: intentionally longer 80 columns --> |
| <pre>function(<span>Type param1, Type param2</span>) <span class="subdued">{...}</span>;</pre> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| </div> |
| </div> |
| |
| <!-- MIN_VERSION --> |
| <p> |
| This function was added in version <b><span></span></b>. |
| If you require this function, the manifest key |
| <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a> |
| can ensure that your extension won't be run in an earlier browser version. |
| </p> |
| </div> <!-- /description --> |
| |
| </div> <!-- /apiItem --> |
| |
| </div> <!-- /apiGroup --> |
| |
| <!-- EVENTS --> |
| <div id="eventsTemplate" class="apiGroup"> |
| <a></a> |
| <h3>Events</h3> |
| <!-- iterates over all events --> |
| <div class="apiItem"> |
| <a></a> |
| <h4>event name</h4> |
| |
| <div class="summary"> |
| <!-- Note: intentionally longer 80 columns --> |
| <span class="subdued">chrome.bookmarks</span><span>onEvent</span><span class="subdued">.addListener</span>(function(<span>Type param1, Type param2</span>) <span class="subdued">{...}</span>); |
| </div> |
| |
| <div class="description"> |
| <p class="todo">Undocumented.</p> |
| <p> |
| A description from the json schema def of the event goes here. |
| </p> |
| |
| <!-- PARAMETERS --> |
| <div> |
| <h4>Parameters</h4> |
| <dl> |
| <div> |
| <div> |
| </div> |
| </div> |
| </dl> |
| </div> |
| </div> <!-- /decription --> |
| |
| </div> <!-- /apiItem --> |
| |
| </div> <!-- /apiGroup --> |
| |
| <!-- TYPES --> |
| <div class="apiGroup"> |
| <a name="types"></a> |
| <h3 id="types">Types</h3> |
| |
| <!-- iterates over all types --> |
| <div class="apiItem"> |
| <a></a> |
| <h4>type name</h4> |
| |
| <div> |
| </div> |
| |
| </div> <!-- /apiItem --> |
| |
| </div> <!-- /apiGroup --> |
| |
| </div> <!-- /apiPage --> |
| </div> <!-- /gc-pagecontent --> |
| </div> <!-- /g-section --> |
| </div> <!-- /codesiteContent --> |
| <div id="gc-footer" --=""> |
| <div class="text"> |
| <p> |
| Except as otherwise <a href="http://code.google.com/policies.html#restrictions">noted</a>, |
| the content of this page is licensed under the <a rel="license" href="http://creativecommons.org/licenses/by/3.0/">Creative Commons |
| Attribution 3.0 License</a>, and code samples are licensed under the |
| <a rel="license" href="http://code.google.com/google_bsd_license.html">BSD License</a>. |
| </p> |
| <p> |
| ©2011 Google |
| </p> |
| |
| <!-- begin analytics --> |
| <script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script> |
| <script src="http://www.google-analytics.com/ga.js" type="text/javascript"></script> |
| |
| <script type="text/javascript"> |
| // chrome doc tracking |
| try { |
| var engdocs = _gat._getTracker("YT-10763712-2"); |
| engdocs._trackPageview(); |
| } catch(err) {} |
| |
| // code.google.com site-wide tracking |
| try { |
| _uacct="UA-18071-1"; |
| _uanchor=1; |
| _uff=0; |
| urchinTracker(); |
| } |
| catch(e) {/* urchinTracker not available. */} |
| </script> |
| <!-- end analytics --> |
| </div> |
| </div> <!-- /gc-footer --> |
| </div> <!-- /gc-container --> |
| </body></html> |