如何在wordpress分类页面上动态添加活动类

function custom_activity_taxonomy() {
    $labels = array(
        'name' => '活动',
        'singular_name' => '活动',
        'search_items' => '搜索活动',
        'all_items' => '所有活动',
        'parent_item' => '父级活动',
        'parent_item_colon' => '父级活动：',
        'edit_item' => '编辑活动',
        'update_item' => '更新活动',
        'add_new_item' => '添加新活动',
        'new_item_name' => '新活动名称',
        'menu_name' => '活动',
    );

    $args = array(
        'hierarchical' => true,
        'labels' => $labels,
        'show_ui' => true,
        'show_admin_column' => true,
        'query_var' => true,
        'rewrite' => array( 'slug' => 'activity' ),
    );

    register_taxonomy( 'activity', array( 'category' ), $args );
}
add_action( 'init', 'custom_activity_taxonomy' );

<?php
$terms = get_terms( 'activity' );
if ( ! empty( $terms ) && ! is_wp_error( $terms ) ) {
    echo '<ul>';
    foreach ( $terms as $term ) {
        echo '<li><a href="' . get_term_link( $term ) . '">' . $term->name . '</a></li>';
    }
    echo '</ul>';
}
?>