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copied!<p>I'm not entirely sure what sort of answer you're looking for, so I apologize if this isn't anything close. ;)</p> <hr> <p>By <strong><em>custom</em></strong>, do you mean <strong><em>custom actions</em></strong>, <strong><em>custom triggers</em></strong>, or truly <strong><em>custom events</em></strong>?</p> <p>E.g.: A <strong><em>custom action</em></strong> would respond to a pre-defined event (say, a mouse click), a <strong><em>custom trigger</em></strong> would be faking a mouse click via script, and a <strong><em>custom event</em></strong> would be a listener that's not defined by the language or isn't readily available.</p> <p>If you're looking for <strong>custom events</strong>, I can't really help you. Though, I don't think there's much support for them in JavaScript.</p> <hr> <p>To define an <strong>Action</strong>...</p> <p>Events are normally established via pre-defined properties of an object, say <code>window.onload</code>. By default, they are all equal to <code>undefined</code> or <code>null</code>. So, to put them to use, you have to set them to the value of a function.</p> <p>You can use an "anonymous" function:</p> <pre><code>window.onload = function (eventObject) { /* ... */ }; </code></pre> <p>Or set them to a function reference (not the same, but similar to a pointer):</p> <pre><code>function handleOnload(eventObject) { /* ... */ } window.onload = handleOnload; /* note the lack of parenthesis */ </code></pre> <p>When the event is triggered, the function is called. So, in either setup, when the page finishes loading, the code you place instead of <code>/* ... */</code> will be executed.</p> <p>There's also more formal methods available for creating events. W3C defines <code>addEventListener</code> while IE uses <code>attachEvent</code>. <a href="http://www.quirksmode.org/js/events_advanced.html" rel="nofollow noreferrer">More info</a>.</p> <p>There are plenty of references available for learning the list of available events. Here's 2 that should give you a good base:</p> <ul> <li><a href="http://www.w3schools.com/jsref/jsref_events.asp" rel="nofollow noreferrer">W3Schools</a></li> <li><a href="https://developer.mozilla.org/en/DOM/element#Event_Handlers" rel="nofollow noreferrer">MDC</a></li> </ul> <hr> <p>The browser usually handles the triggering of events -- either for browser events (<code>onload</code>) or user events (<code>onclick</code>). The property and function are meant to respond.</p> <p><strong>Triggering</strong> your own event isn't the easiest thing to accomplish. To completely define an <code>Event</code> object takes some work -- and <a href="http://www.javascriptkit.com/jsref/event.shtml" rel="nofollow noreferrer">varies between browsers</a>.</p> <p>Though, if you don't need the <code>Event</code> object, you can simply call the event:</p> <pre><code>window.onload(); </code></pre>

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