Version 4 supported
This version of Silverstripe CMS is still supported though will not receive any additional features. Go to documentation for the most recent stable version.

Extending existing ModelAdmin

Sometimes you'll work with ModelAdmins from other modules. To customise these interfaces, you can always subclass. But there's also another tool at your disposal: The Extension API.

use SilverStripe\Core\Extension;

class MyAdminExtension extends Extension 
    // ...
    public function updateEditForm(&$form) 
        $form->Fields()->push(/* ... */)

Now enable this extension through your [config.yml](/topics/configuration) file.

    - MyAdminExtension

The following extension points are available: updateEditForm(), updateSearchContext(), updateSearchForm(), updateList(), updateImportForm.