<code>
class Test extends Page {
static $db = array(
   );
static $has_one = array(
);

   function getCMSFields() {
   $fields = parent::getCMSFields();

   $fields->addFieldsToTab(
   'Root.Content.Main',
   array(
      new CheckboxSetField(
    $name = "topics",
    $title = "I am interested in the following topics",
    $source = array(
    "1" => "Technology",
    "2" => "Gardening",
    "3" => "Cooking",
    "4" => "Sports"
    ),
    $value = "1"
   )
   )
   );
   
return $fields;
}

}
</code>

I realize this is a very basic question, but I am new to silverstripe and I am stumped.

How do I declare the variable "topics", as it stands, the checkboxes appear fine in the admin part, but I can't save them (they always revert back to the default value) nor display results.

Thank you it's what I needed.