smalps

Hey ezeuielzc:

I had a similar goal; I wanted to restrict access to categories based on the user’s role. This is how I did it:

1. In /wp-admin/includes/template.php –

I replaced this line:
$cats = get_categories("parent=$parent&hide_empty=0&fields=ids");

With this:

if (!$parent) {
   $cats = get_categories("parent=$parent&hide_empty=0&fields=ids");
} else {
$cats = get_categories("child_of=$parent&hide_empty=0&fields=ids");
}

2. /wp-admin/includes/template.php –

I replaced this function:

function dropdown_categories( $default = 0 ) {
	write_nested_categories( get_nested_categories( $default) );
}

With this function:

function dropdown_categories( $default = 0, $parent = 0 ) {
	write_nested_categories( get_nested_categories( $default, $parent) );
}

3. /wp-admin/edit-form-advanced.php –

I replaced this line:
<ul id="categorychecklist"><?php dropdown_categories(); ?></ul></div>

With this line:
<ul id="categorychecklist"><?php if ( !current_user_can('manage_categories') ) { dropdown_categories(0,5); } else { dropdown_categories();} ?></ul></div>

5 – being my category ID which I wanted only the child of.
I used !current_user_can to control when this would be called. Currently child_of 5 is only called when the user is no admin or editor.

* – If there is a new update this will most likely be overwritten.