Add new Sitemap type in OctoberCMS

Plugin.php

<?php

public function boot()
{
    // Add RainLab.Blog articles to sitemap
    Event::listen('pages.menuitem.listTypes', function() {
        return [
            'blog-post' => 'Blog post',
            'all-blog-posts' => 'All blog posts'
        ];
    });

    Event::listen('pages.menuitem.getTypeInfo', function($type) {
        if ($type == 'blog-category' || $type == 'all-blog-categories')
            return Category::getMenuTypeInfo($type);
    });

    Event::listen('pages.menuitem.resolveItem', function($type, $item, $url, $theme) {
        if ($type == 'blog-category' || $type == 'all-blog-categories')
            return Category::resolveMenuItem($item, $url, $theme);
    });
}