Enable zip extension for php with apache by:

1- Un-commenting zip.so in /opt/lampp/etc/php.ini. (The latest version of XAMPP, as of this article, is compiled with zip support for PHP but you need to follow the few steps mentioned here to enable it and make it work).

2- Un-commenting and updating the path of the extension_dir in php.ini (extension_dir = “/opt/lampp/lib/php/extensions/no-debug-non-zts-20100525”)

3- Downloading zip.so into the Extension Dir.

You can download the modified php.ini, httpd.conf and the zip.so described above here:

Download php.ini 
Download zip.so 
Download http.conf file

Clear browser cache.

Stop and start XAMPP
/opt/lampp/lampp stop
/opt/lampp/lampp start

Reference article : http://www.bostonit.com/