From 69b90b43ce64cba75235c74b19c50acb5378fc68 Mon Sep 17 00:00:00 2001
From: Andrea Giudiceandrea <andreaerdna@libero.it>
Date: Fri, 28 Feb 2025 08:04:12 +0100
Subject: [PATCH] Fix Value Map widget with NULL value and field length < 38

---
 src/gui/editorwidgets/qgsvaluemapconfigdlg.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/gui/editorwidgets/qgsvaluemapconfigdlg.cpp b/src/gui/editorwidgets/qgsvaluemapconfigdlg.cpp
index 8d6c1ae5b4b5..e3ce3671b7d0 100644
--- a/src/gui/editorwidgets/qgsvaluemapconfigdlg.cpp
+++ b/src/gui/editorwidgets/qgsvaluemapconfigdlg.cpp
@@ -246,6 +246,11 @@ void QgsValueMapConfigDlg::updateMap( const QList<QPair<QString, QVariant>> &lis
 
 QString QgsValueMapConfigDlg::checkValueLength( const QString &value )
 {
+  if ( value == QgsValueMapFieldFormatter::NULL_VALUE )
+  {
+    return value;
+  }
+
   if ( layer()->fields().exists( field() ) )
   {
     const QgsField mappedField { layer()->fields().field( field() ) };