Check for existing labels in baritemmodelhandler

Also add setting column and row labels in tst_qmltheme.

Fixes: QTBUG-130722
Pick-to: 6.8
Change-Id: I09cc382957cb3d9ccca0b72ae3723978157726ac
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>
Reviewed-by: Kwanghyo Park <kwanghyo.park@qt.io>

src/graphs3d/data/baritemmodelhandler.cpp

@@ -270,8 +270,15 @@ void BarItemModelHandler::resolveModel()
             }
         }
 
-        rowLabels = rowList;
-        columnLabels = columnList;
+        if (!m_proxy->series()->rowLabels().isEmpty())
+            rowLabels = m_proxy->series()->rowLabels();
+        else
+            rowLabels = rowList;
+        if (!m_proxy->series()->columnLabels().isEmpty())
+            columnLabels = m_proxy->series()->columnLabels();
+        else
+            columnLabels = columnList;
+
         m_columnCount = columnList.size();
 
         delete matchCountMap;

tests/manual/qmltheme/qml/qmltheme/main.qml

@@ -124,6 +124,23 @@ Item {
                 // If you want to check with series colors, uncomment these
                 // baseGradient: customGradient
                 // baseColor: barColor.color
+                columnLabels: [
+                    "col 1",
+                    "col 2",
+                    "col 3",
+                    "col 4",
+                    "col 5",
+                    "col 6",
+                ]
+                rowLabels: [
+                    "row 1",
+                    "row 2",
+                    "row 3",
+                    "row 4",
+                    "row 5",
+                    "row 6",
+                ]
+
                 ItemModelBarDataProxy {
                     id: barProxy
                     itemModel: ListModel {