Two Themes

or you go to index2.php

There is no index2.php and WP will never work with a filename like that – so forget it.

You use ONE theme in one WP installation.
You van, however, install some theme-switcher plugin, that lets you (and visitors) select from the installed themes.

it works just fine on my site:
https://www.spiritsurfers.net/index2.php

What I envision is that index2 sets a variable or something that overrides the current theme selection. Obviously I’d have to modify some wordpress code to make this happen.

I’ll look into the theme switcher since it’ll probably give me a clue as to which code I need to change.

Look at wp-includes/theme.php.

It looks as if you could use the stylesheet and template filters to set the theme, just by modifying the values sent through to point to the theme directory you want. Everything else builds on those two.

Or you could define TEMPLATEPATH and STYLESHEETPATH (see wp-settings.php) to what you want. This will mean that WP tries to define already defined constants in wp-settings.php, but that wouldn’t be a problem in practice. Doing it with filters is aesthetically more appealing.

I used the hack method, setting TEMPLATEPATH and STYLESHEETPATH in the index2.php. It works great, thanks! I thought I’d have to rewrite some code.