From 3f19bcbeef467afe0f7cd27ab8a634efbf72e17e Mon Sep 17 00:00:00 2001
From: Abdullah Tahiri <abdullah.tahiri.yo@gmail.com>
Date: Sat, 18 Mar 2023 06:49:23 +0100
Subject: [PATCH] Sketcher: Elements Widget - Fix crash when moving external
 geometry to another layer

====================================================================================

As reported:
https://forum.freecad.org/viewtopic.php?p=667426#p667426

Support for moving external geometry to another layer will come in the future.
---
 src/Mod/Sketcher/Gui/TaskSketcherElements.cpp | 22 +++++++++++++------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/TaskSketcherElements.cpp b/src/Mod/Sketcher/Gui/TaskSketcherElements.cpp
index a851f342d2..0da222ab49 100644
--- a/src/Mod/Sketcher/Gui/TaskSketcherElements.cpp
+++ b/src/Mod/Sketcher/Gui/TaskSketcherElements.cpp
@@ -41,6 +41,7 @@
 #include <Gui/Application.h>
 #include <Gui/BitmapFactory.h>
 #include <Gui/Command.h>
+#include <Gui/Notifications.h>
 #include <Gui/Selection.h>
 #include <Gui/SelectionObject.h>
 #include <Gui/ViewProvider.h>
@@ -386,12 +387,19 @@ void ElementView::changeLayer(int layer)
 
         bool anychanged = false;
         for(auto geoid : geoids) {
-            auto currentlayer = getSafeGeomLayerId(geometry[geoid]);
-            if( currentlayer != layer) {
-                auto geo = geometry[geoid]->clone();
-                setSafeGeomLayerId(geo, layer);
-                newgeometry[geoid] = geo;
-                anychanged = true;
+            if(geoid >= 0) { // currently only internal geometry can be changed from one layer to another
+                auto currentlayer = getSafeGeomLayerId(geometry[geoid]);
+                if( currentlayer != layer) {
+                    auto geo = geometry[geoid]->clone();
+                    setSafeGeomLayerId(geo, layer);
+                    newgeometry[geoid] = geo;
+                    anychanged = true;
+                }
+            }
+            else {
+                Gui::TranslatedNotification(sketchobject,
+                                            QObject::tr("Unsupported visual layer operation"),
+                                            QObject::tr("It is currently unsupported to move external geometry to another visual layer. External geometry will be omitted"));
             }
         }
 
@@ -700,7 +708,7 @@ private:
     };
 
 };
-} // namespace SketcherGui
+}
 
 enum class GeoFilterType {
     NormalGeos,