I'm currently creating a custom Walker_Category class to make some changes to how category selection works in a custom taxonomy. The taxonomy is called 'page_category'. I want to put this in a normal context metabox, so I've written the following:
class Walker_Smartcat extends Walker_Category {
}
function custom_check() {
$args = array(
'descendants_and_self' => 0,
'selected_cats' => false,
'popular_cats' => false,
'walker' => 'Walker_Smartcat',
'taxonomy' => 'page_category',
'checked_ontop' => false,
'echo' => true
);
wp_terms_checklist( get_the_ID(), $args );
}
function custom_check_meta() {
add_meta_box( 'custom', 'Test', 'custom_check', 'page', 'normal', 'high', null );
remove_meta_box( 'page_categorydiv', 'page', 'side' );
}
add_action( 'add_meta_boxes', 'custom_check_meta' );
So I've not currently added any custom functionality to my extended walker (intentional to make sure saving works - this will be modified at a later date).
Now, when I save it sometimes saves the categories correctly, but if I then uncheck a category and resave it doesn't seem to do this. Am I missing something obvious? it also happens if I use the default "Walker_Category".
Edit: I've narrowed this down. It seems that it always expects one thing to be checked, if there's only one and you remove it then it doesn't save. This doesn't happen with the default categories. Would still appreciate any insights as to why this might happen.