From d9a632b5dca36917575b69b6ed083cb598796d03 Mon Sep 17 00:00:00 2001
From: "github-actions[bot]" <github-actions[bot]@users.noreply.github.com>
Date: Tue, 7 Jul 2020 19:02:48 +0000
Subject: [PATCH] fixes invalid relation in search form

---
 .../editorwidgets/qgsrelationreferencesearchwidgetwrapper.cpp  | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/gui/editorwidgets/qgsrelationreferencesearchwidgetwrapper.cpp b/src/gui/editorwidgets/qgsrelationreferencesearchwidgetwrapper.cpp
index d2df062ceb61..38a755e64171 100644
--- a/src/gui/editorwidgets/qgsrelationreferencesearchwidgetwrapper.cpp
+++ b/src/gui/editorwidgets/qgsrelationreferencesearchwidgetwrapper.cpp
@@ -207,6 +207,9 @@ void QgsRelationReferenceSearchWidgetWrapper::initWidget( QWidget *editor )
   }
 
   QgsRelation relation = QgsProject::instance()->relationManager()->relation( config( QStringLiteral( "Relation" ) ).toString() );
+  // if no relation is given from the config, fetch one if there is only one available
+  if ( !relation.isValid() && !layer()->referencingRelations( mFieldIdx ).isEmpty() && layer()->referencingRelations( mFieldIdx ).count() == 1 )
+    relation = layer()->referencingRelations( mFieldIdx )[0];
   mWidget->setRelation( relation, false );
 
   mWidget->showIndeterminateState();