silverstripe groupby subpages by first letter alphabetically

Question

Silverstripe: I want to have my menus to have its list sorted and grouped by alphabetically. I have followed every step in this documentation in using the GroupBy method her and to no avail.
Basically I want my subpages to appear as follows in the menu:

• B
  • Blog
• C
  • CMS Workflow
  • Custom Translations
• D
  • Database Plumber
  • ...

What is actually happening after following doing what is in the documentation is that i get an empty list, basically the $GroupedModules.GroupedBy(TitleFirstLetter) is not working.

The thing I think I may be missing here, is the creating of the Module class, I don't know where to create it, should it exist in the Page.php? Also, should be named Module?

Thanks in advance

Answer 1

The documentation you linked to shows how to do a group list of dataobjects (Module in their example). You want do a grouped list of pages, so you need to alter the code a little to fit your needs.

Page.php

class Page extends SiteTree {

    // ...

    public function getTitleFirstLetter() {
        return $this->Title[0];
    }

    public function getGroupedChildren() {
        return GroupedList::create($this->Children()->sort('Title'));
    }

}

Your template

<% loop $GroupedChildren.GroupedBy(TitleFirstLetter) %>
    <h3>$TitleFirstLetter</h3>
    <ul>
        <% loop $Children %>
            <li>$Title</li>
        <% end_loop %>
    </ul>
<% end_loop %>