From 9cbe86c13372560fb769b0f9fe5ebe6c4fd32d97 Mon Sep 17 00:00:00 2001
From: Devid Messner <devid.messner@konverto.eu>
Date: Wed, 24 Sep 2025 15:28:03 +0200
Subject: [PATCH] [BUGFIX] Support multiple values in SelectViewHelper

The SelectViewHelper in v13.0.0 provided a `multiple` attribute, but
handling of multiple selected values was not working. This commit fixes
the issue by correctly reading and displaying multiple values.

Resolves:  #663
---
 Classes/ViewHelpers/Form/SelectViewHelper.php | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Classes/ViewHelpers/Form/SelectViewHelper.php b/Classes/ViewHelpers/Form/SelectViewHelper.php
index 3160f5bf7..14c9dc2a5 100644
--- a/Classes/ViewHelpers/Form/SelectViewHelper.php
+++ b/Classes/ViewHelpers/Form/SelectViewHelper.php
@@ -32,7 +32,7 @@ class SelectViewHelper extends AbstractFormFieldViewHelper
     public function initialize(): void
     {
         parent::initialize();
-        $this->tag->addAttribute('data-selected-value', $this->getSelectedValue());
+        $this->tag->addAttribute('data-selected-value', is_array($this->getSelectedValue()) ? implode(',', $this->getSelectedValue()) : $this->getSelectedValue());
     }
 
     public function initializeArguments(): void
@@ -313,7 +313,6 @@ protected function isSelected(mixed $value): bool
      */
     protected function getSelectedValue()
     {
-        $selectedValues = null;
         $this->setRespectSubmittedDataValue(true);
         $value = $this->getValueAttribute();
         if (!is_array($value) && !$value instanceof \Traversable) {
@@ -322,6 +321,10 @@ protected function getSelectedValue()
                 return $selectedValues;
             }
         }
+        $selectedValues = [];
+        foreach ($value as $selectedValueElement) {
+            $selectedValues[] = $this->getOptionValueScalar($selectedValueElement);
+        }
 
         // set preselection from TypoScript
         if (! $this->renderingContext instanceof RenderingContext) {