keeping active page using include_once to include site navigation - php

Question

Another, what could be a silly, question. I have a very in-depth navigation menu on my clients site. I don't mind doing the hard slog now changing all the pages and links to .php - will save mucho time in the future. I want to use <?php include_once("nav.php"); ?> to pull this into every page. At the moment the parent item that is active will be highlighted depending on which child page is being viewed. The menu structure is currently just part of each of the .html page.
HTML markup:
<div id="navigation-wrapper">
<nav id="main-navigation">
<ul class="main-menu">
<li><span aria-hidden="true" class="li_display nav_icon"></span>About
<ul>
<li>Corporate Profile</li>
<li>Board of Directors</li>
<li>Operating Divisions</li>
<li>Organisational Chart</li>
<li>Corporate Documentation</li>
</ul>
</li>
<li><span aria-hidden="true" class="li_news nav_icon"></span>Investor
<ul>
<li>Overview</li>
<li>Financial</li>
<li>News</li>
<li>Events</li>
<li>General</li>
<li>Register for Alerts</li>
</ul>
</li>
<li><span aria-hidden="true" class="li_bulb nav_icon"></span>Products
<ul>
<li>Mecer</li>
<li>Hardware
<ul>
<li>APC</li>
<li>Acer</li>
<li>ASUS</li>
<li>E-Beam</li>
<li>Fujitsu</li>
<li>Huawei</li>
<li>Lenovo</li>
<li>Microsoft</li>
<li>NEC</li>
<li>Samsung</li>
<li>Toshiba</li>
</ul>
</li>`enter code here`
<li>Mustek Energy
<ul>
<li>Solar Panels</li>
<li>LED Lighting Solutions</li>
</ul>
</li>
<li>Mustek Solutions
<ul>
<li>Mustek Cloud Computing</li>
<li>Mustek Digital Signage</li>
<li>Mustek POS Solutions</li>
<li>Mustek Security Technology</li>
</ul>
</li>
<li>Networking Solutions
<ul>
<li>D-Link</li>
<li>Huawei</li>
<li>Miniflex</li>
<li>NEC</li>
<li>NComputing</li>
</ul>
</li>
<li>Printing Solutions
<ul>
<li>Brother</li>
<li>Epson</li>
</ul>
</li>
<li>Complete Product Catalogue</li>
</ul>
</li>
<li><span aria-hidden="true" class="li_settings nav_icon"></span>Support
<ul>
<li>DealerNet</li>
<li>Dealer Application Form</li>
<li>Dealer Locator</li>
<li><a href="http://downloadcenter.mustek.co.za/list.php?dir=Repository" target=_blank>Download Latest Drivers</a></li>
<li>Mecer EyeSPY</li>
</ul>
</li>
<li><span aria-hidden="true" class="li_phone nav_icon"></span>Contact
<ul>
<li>Branches</li>
<li>Customer Liaison</li>
<li>Investors</li>
<li>Sales Queries</li>
<li>Technical Queries</li>
<li>Careers</li>
</ul>
</li>
</ul>
</nav>
</div>
As you can see the class="active-page" dictates which parent icon to show. I read somewhere that by adding <?php $page = "page-name"; ?> it will say which page this is and will act like the class="active-page". Do I need to create an id for the page in the nav.php file that it will reference?
Sorry guys, but my knowledge of PHP is very limited, but I am trying to learn the basics on the fly. Any help is greatly appreciated!

Answer 1

Just use an if-statement to add "active-page" as class to the current active page:
<li><span aria-hidden="true" class="li_display nav_icon"></span>About
You then need to define a constant ACTIVE_PAGE before including your navigation.
<?php
define ('ACTIVE_PAGE', "About");
include ('yournav.php');
?>
This should work and is okay if you do not have too many pages.
An alternative could be in getting the currently visited page via
$_SERVER['PHP_SELF']
and then add to navigation.php which html-file shall be called for which entry in php_self. The advantage would be that you have all your navigation-based code in one place. Personally, I would prefer this last solution.