Context Menu

ContextMenu

A pop-up menu triggered by a right mouse click (Windows, Linux, etc), or control-click (Mac).

The idea is that your graphical objects are nouns and the context menu provides appropriate verbs (NounsAndVerbs), very similar to messages to an object. This a common UserInterfacePattern? also seen in SmalltalkLanguage and NakedObjects.

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Q: How does one create a ContextMenu for a Web application?

A: Use JavaScript. An example (for InternetExplorer) is given at http://javascript.internet.com/page-details/right-click-menu.html.

It's claimed that if you use Netscape, you need at least Netscape 6. An example for NS6 (or IE5+) is given at http://www.dynamicdrive.com/dynamicindex1/contextmenu.htm.

Q: Why can't I create a ContextMenu for a Web application in PHP/CeeLanguage/MySql/etc?

A: Bringing up a context menu must be done in JavaScript because by the time the browser gets the page, PHP & MySql are no longer part of the picture. A browser requests a Web page from a server; the server uses PHP and MySql to build the page. Once the page is built, PHP & MySql's job is done. Anything that happens once the page is returned (e.g., activating a context menu) must be done on the browser side. That means JavaLanguage, JavaScript, MacromediaFlash, etc. Check out any book on Web app development if this isn't clear.

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You can conditionally output JavaScript with PHP though. eg.

    function js_alert($msg) {
        ?>
        <script type="text/javascript">
            <!--
            alert('<?php echo $msg; ?>');
            -->
        </script>
        <?php
        exit;
    }

Sloppy as hell, but it works, and points out why PHP is a Hypertext Preprocessor. Something similar could be done using PHP to build the menu then use Javascript to fire the event.