blob: 1e06a3205c6c7de47014d253f2cc5158dde9ac2e [file] [log] [blame]
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
content="text/html; charset=iso-8859-1">
<title>How to extend/customize HTML checker</title>
<link rel="stylesheet" type="text/css" href="../base.css">
<h1>How to extend/customize HTML checker</h1>
<h2 id="checker">Step 1. Develop IHtmlChecker implementation</h2>
<li>Receive IHtmlCheckTarget that contains target HTML information as HtmlEvalUtil
<ul class="nospace">
<li>getTarget(): returns target DOM selected in preference page</li>
<li>getSrcDom(): returns DOM based on original HTML source</li>
<li>getLiveDom(): returns Live-DOM snapshot of IE</li>
<li>provides other useful data for accessibility check, such as Array of 'href' values, image elements, anchor elements, table elements, etc.</li>
(Please see <a href="../../reference/api/org/eclipse/actf/visualization/eval/html/HtmlEvalUtil.html">HtmlEvalUtil</a> for more details.)
<li>Check accessibility of content by using DOM API and data from HtmlEvalUtil</li>
<li>Create and return IProblemItem for each accessibility issue
<pre>IProblemItem problem = new ProblemItemImpl("CheckItemID");</pre>
(Please see org.eclipse.actf.examples.adesigner.eval.html.internal.CheckEngine as reference implementation.)
<h2>Step 2. Write XML and properties file for configurations</h2>
<h3 id="guideline">Guideline XML</h3>
<p>includes guideline item information, such as name, URL of help page, etc.<br/>
<a href="wcag20.xml">Reference implementation for WCAG 2.0</a>
<h3>Check Item XML</h3>
<p>defines mapping between <a href="#checker">implemented check items</a> and <a href="#guideline">guideline items</a>.<br/>
It also defines corresponding criteria for each check item, such as Compliance, Listenability, My Company's guide, etc. <br/>
<a href="checkitem.xml">Reference implementation</a>
<h3>Properties file for error messages</h3>
<p>defines error messages for each <a href="#checker">implemented check items</a>. Use id defined in Check Item XML as key of the properties.
<a href="">Reference implementation</a>
<h2>Step 3. Implement ICheckerInfoProvider and refer your XML/properties file</h2>
<p>Example implementation
public class MyCheckerInfoProvider implements ICheckerInfoProvider {
private static final String BUNDLE_NAME =
"org.eclipse.myproject.description"; //$NON-NLS-1$
private static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle.getBundle(BUNDLE_NAME);
public InputStream[] getCheckItemInputStreams() {
InputStream is = OdfChecker.class.getResourceAsStream("resources/checkitem.xml");
return new InputStream[] { is };
public InputStream[] getGuidelineInputStreams() {
InputStream is = OdfChecker.class.getResourceAsStream("resources/guideline.xml");
return new InputStream[] { is };
public ResourceBundle getDescriptionRB() {
<h2>Step 4. Register your checker as an extension</h2>
<p>Register your checker implementation by using
<a href="../../reference/extension-points/common/org_eclipse_actf_visualization_eval_checkers.html">org.eclipse.actf.visualization.eval.checkers</a> Extension Points.
<div class="figure"><img src="../img/checker_extension.gif" alt=""/></div>