Remove/Add widgets from/to the Available Widgets pool

Question

Is it possible to remove/add widgets from/to the Available Widgets pool (either by plugin or editing core files)?

There are 3 widget files located at:

/wp-includes/widgets.php

/wp-admin/widgets.php

/wp-admin/includes/widgets.php

I have tried to change both the code and the widget variables but nothing happened.

thanks

Answer 1

You can use the function unregister_widget to remove widgets.

E.g. you can remove the Calendar widget with:

function my_widgets_init() {
    unregister_widget( 'WP_Widget_Calendar' );
}
add_action('widgets_init', 'my_widgets_init');

To add widgets, use the Widgets API.