Cannot display hierarchical categories list of all blog's categories (including children)

[kwa1975]

When trying to display a hierarchical categories list including children, one could write the following PHP line in his/her theme:

wp_list_cats('hierarchical=1&children=1&child_of=0');

Since the parent category of all the other categories is 0, we had to set child_of to zero.

However, it appears the wp_list_cats() function uses the value 0 of child_of as both an integer value to limit the categories display to a given parent category (here, we want to limit it to category 0) AND as a boolean value, meaning 0 means "false" and the children of category 0 won't be displayed.

To fix this issue, another parameter should be added or a different value for child_of should be used.

[MichaelH]

Can't duplicate this problem at 2.0.1 or 2.0.1 alpha1 but I may not understand the issue.

Using your example wp_list_cats('hierarchical=1&children=1&child_of=0') or wp_list_cats('hierarchical=1&children=1') or wp_list_cats() returns the same thing--all categories (see Note).

Note: If a parent category has no posts, then neither the parent or its children will display using the above examples. Using hide_empty=0 would force them to display.

Interestingly, this returns no categories; wp_list_cats('hierarchical=1&children=1&child_of=')

[johnbillion]

Closing as wontfix for two reasons.

1. wp_list_cats has been deprecated in favour of wp_list_categories
2. It's not possible to create a category with an ID of 0 (unless you directly edit the DB, then you're creating your own problems...)