Slider.php

<?php
class Slider extends DataObject {
	public static $db = array(
		"Link" => "Text"
	);

	public static $has_one = array(
		"Image" => "Image"
	);

	public static $searchable_fields = array(
		"ID",
		"Link"
	);

	public static $summary_fields = array(
		"TinyThumbnail" => "Image",
		"Sorting",
		"Title",
		"Link"
	);

	public function getTitle() {
		if(($image = $this->Image()) && $image->exists())
			return $image->Title;

		return $this->ID;
	}

	public function getTinyThumbnail() {
		return $this->Image()->CroppedImage(50, 50);
	}
}