Checking selected state

Example for StackOverflow question

HTML

<link rel="stylesheet" href="https://ajax.googleapis.com/ajax/libs/dojo/1.6/dojo/resources/dojo.css">
<link rel="stylesheet" href="https://ajax.googleapis.com/ajax/libs/dojo/1.6/dijit/themes/claro/claro.css">
<!-- Main checking button -->
<div id="check" dojoType="dijit.form.Button">Check if second tab is active</div>

<!-- Container -->
<div id="tabs" dojoType="dijit.layout.TabContainer" style="width: 300px; height: 300px;">
    <div id="tab1" dojoType="dijit.layout.ContentPane" title="Tab One">Tab One</div>
    <div id="tab2" dojoType="dijit.layout.ContentPane" title="Tab Two">Tab Two</div>
    <div id="tab3" dojoType="dijit.layout.ContentPane" title="Tab Three">Tab Three</div>
</div> <!-- #tabs -->

JavaScript

// Requires
dojo.require('dojo.parser');
dojo.require('dijit.form.Button');
dojo.require('dijit.layout.TabContainer');
dojo.require('dijit.layout.ContentPane');

// Do something once DOM/requires are ready
/*
dojo.ready(function() {
    var tab2 = dijit.byId('tab2');
    dojo.connect(dijit.byId('check'), 'onClick', function() {
        if (tab2.get('selected')) {
            alert('Tab 2 is selected');
        } else {
            alert('Tab 2 is NOT selected');
        }
    });
});*/

require(["dijit/registry",  "dojo/ready", "dojo/domReady!"], function (registry, ready) {
    ready(function () { //wait till dom is parsed into dijits
        if (dijit.byId('tabContainer').selectedChildWidget == dijit.byId('tab2'))
            alert('Yes, we found it!');
    });
});