[BUGFIX] Flash messages are not shown with AJAX requests

Direct DOM manipulation is avoided in favour of using the
top.Notification object to trigger TYPO3 7 native notifications.

Resolves: #71453
Related: #56561
Releases: master
Change-Id: I8c39d8100153b106e89ee1e7259ff1a0cc7ad572
Reviewed-on: https://review.typo3.org/44652


Reviewed-by: Helmut Hummel <helmut.hummel@typo3.org>
Tested-by: Helmut Hummel <helmut.hummel@typo3.org>
Reviewed-by: Frank Nägler <frank.naegler@typo3.org>
Tested-by: Frank Nägler <frank.naegler@typo3.org>

typo3/sysext/backend/Classes/Template/DocumentTemplate.php

@@ -1789,7 +1789,22 @@ function jumpToUrl(URL) {
      */
     public function renderQueuedFlashMessages(ServerRequestInterface $request, ResponseInterface $response)
     {
-        $response->getBody()->write($this->getFlashMessages());
+        /** @var $flashMessageService \TYPO3\CMS\Core\Messaging\FlashMessageService */
+        $flashMessageService = GeneralUtility::makeInstance(\TYPO3\CMS\Core\Messaging\FlashMessageService::class);
+        /** @var $defaultFlashMessageQueue \TYPO3\CMS\Core\Messaging\FlashMessageQueue */
+        $defaultFlashMessageQueue = $flashMessageService->getMessageQueueByIdentifier();
+        $flashMessages = $defaultFlashMessageQueue->getAllMessagesAndFlush();
+
+        $messages = [];
+        foreach ($flashMessages as $flashMessage) {
+            $messages[] = [
+                'title' => $flashMessage->getTitle(),
+                'message' => $flashMessage->getMessage(),
+                'severity' => $flashMessage->getSeverity()
+            ];
+        }
+
+        $response->getBody()->write(json_encode($messages));
         return $response;
     }
 

typo3/sysext/backend/Resources/Public/JavaScript/DragUploader.js

@@ -277,12 +277,9 @@ define(['jquery', 'moment', 'nprogress', 'TYPO3/CMS/Backend/Modal', 'TYPO3/CMS/L
 						url: TYPO3.settings.ajaxUrls['flashmessages_render'],
 						cache: false,
 						success: function(data) {
-							var messages = $('#typo3-messages');
-							if (messages.length == 0) {
-								$('#typo3-inner-docbody').prepend(data);
-							} else {
-								messages.replaceWith(data);
-							}
+							$.each(data, function(index, flashMessage) {
+								top.TYPO3.Notification.showMessage(flashMessage.title, flashMessage.message, flashMessage.severity);
+							});
 						}
 					});
 				}