API-CHANGE: overriding DMS delete button (not quite working yet)

code/DMSDocument.php

@@ -470,6 +470,8 @@ class DMSDocument extends DataObject implements DMSDocumentInterface {
 
 		$fields->add($UploadField);
 		$fields->add($pagesGrid);
+		$fields->add(FormAction::create('dod', _t('GridFieldDetailForm.Delete', 'Delete'))
+						->addExtraClass('ss-ui-action-destructive'));   //delete button
 
 
 		return $fields;

code/DMSSiteTreeExtension.php

@@ -25,6 +25,10 @@ class DMSSiteTreeExtension extends DataExtension {
 		$gridFieldConfig->getComponentByType('GridFieldDataColumns')->setDisplayFields($modelClass::$display_fields)
 			->setFieldCasting(array('LastChanged'=>"Date->Ago"))
  			->setFieldFormatting(array('FilenameWithoutID'=>'<a target=\'_blank\' class=\'file-url\' href=\'$DownloadLink\'>$FilenameWithoutID</a>'));
+
+		//override delete functionality with this class
+		$gridFieldConfig->getComponentByType('GridFieldDetailForm')->setItemRequestClass('DMSGridFieldDetailForm_ItemRequest');
+
 		$gridField = GridField::create(
 			'Documents', 
 			false, 

code/cms/DMSGridFieldDetailForm.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * Custom ItemRequest class the provides custom delete behaviour for the CMSFields of DMSDocument
+ */
+class DMSGridFieldDetailForm_ItemRequest extends GridFieldDetailForm_ItemRequest {
+
+
+	function ItemEditForm() {
+		$form = parent::ItemEditForm();
+		//could try and remove the delete button here (or just hide it in css)
+
+		return $form;
+	}
+
+
+	/**
+	 * Overriding delete functionality with our own
+	 * @param $data
+	 * @param $form
+	 * @return mixed
+	 * @throws ValidationException
+	 */
+	function doDelete($data, $form) {
+		try {
+			$toDelete = $this->record;
+			if (!$toDelete->canDelete()) {
+				throw new ValidationException(_t('GridFieldDetailForm.DeletePermissionsFailure',"No delete permissions"),0);
+			}
+
+			$toDelete->delete();
+		} catch(ValidationException $e) {
+			$form->sessionMessage($e->getResult()->message(), 'bad');
+			return Controller::curr()->redirectBack();
+		}
+
+		$message = sprintf(
+			_t('GridFieldDetailForm.Deleted', 'Deleted %s %s'),
+			$this->record->singular_name(),
+			'<a href="' . $this->Link('edit') . '">"' . htmlspecialchars($this->record->Title, ENT_QUOTES) . '"</a>'
+		);
+
+		$form->sessionMessage($message, 'good');
+
+		//when an item is deleted, redirect to the revelant admin section without the action parameter
+		$controller = Controller::curr();
+		$noActionURL = $controller->removeAction($data['url']);
+		$controller->getRequest()->addHeader('X-Pjax', 'Content'); // Force a content refresh
+
+		return $controller->redirect($noActionURL, 302); //redirect back to admin section
+	}
+
+}