Hi,
Using Theme COmpatibility screen:
Options here allow you to change the wrappers and make any theme compatible
Using Filters:
There are several filters throughout the code to hook into targeted part of the output of all pages: http://docs.wpgeodirectory.com/codex_project/geodirectory_filters/
Actions:
Each template is broken down in several actions.
For each do_action, you will find a corresponding create_action in geodirectory_template_actions.php
In the create_action you will find the name of the function that is responsible for that part of the output.
If for example you want to modify the output of the listings/category pages you will open geodirectory-templates/geodir-listing.php and see that the action we need is :
do_action('geodir_listings_content');
we will search for geodir_listings_content in geodirectory_template_actions.php which will bring up:
add_action('geodir_listings_content', 'geodir_action_listings_content', 10);
on line 1786
Now you have the name of the function: geodir_action_listings_content (which is normally few lines below, like in this case on line 1792).
function geodir_action_listings_content()
{ //function here }
All you have to do now is :
1) copy the entire function in your active theme functions.php
2) rename the function to something like : my_geodir_action_listings_content
3) edit the function as needed
4) remove the original action :
remove_action('geodir_listings_content', 'geodir_action_listings_content', 10);
5) add the action back calling your customized function:
add_action('geodir_listings_content', 'my_geodir_action_listings_content', 10);
If you are developing a custom theme feel free to add Stiofan to skype for advise.