[Typo3-dev] Filtering by categories in extension

[Alexander Langer]

Also sprach Sergio Sánchez (sergio at corecanarias.com):

> 	I have created a new tt_content field for the extension to select 
> 	the category I want to display in the list, but extension manager  didn't 
> make any code about that so in the list plugin lists all categories. I 
> have been lookit at API Doc but I haven't found anything useful for me.

Assuming, the field you extended tt_content with is called
"tx_yourext_category", you can get this value by doing:

	$theValue = $this->cObj->data['tx_yourext_category'];

and add $theValue to the MySQL query whereever you want to use it.

(e.g. set $selectConf['where'] to something like 'AND category=$theValue',
if you are using $this->cObj->getQuery() -- see getQuery() docs.

Alex