Album-based content using a gallery image as a thumbnail

Overview

An album-based content class, where its thumbnail record is a pointer to one of the image link records its the gallery.

PHP class structure

[MyContentClass] extends album_class
 |
 +- $site_section:site_section_class
 |   | 
 |   +- $gallery_thumbnail:boolean_checkbox_input_class
 |   |   |
 |   |   +- value=true
 |   |
 |   +- [...]
 |
 +- $gallery:gallery_class
 |   |
 |   +- $tn:image_link_class 
 |   |
 |   +- [...]
 |
 +- [...]