Draft: More solid closing of Draft commands - fixes #2532

src/Mod/Draft/DraftGui.py

@@ -251,13 +251,17 @@ class DraftTaskPanel:
         if hasattr(FreeCADGui,"draftToolBar"):
             return FreeCADGui.draftToolBar.validatePoint()
         else:
-            FreeCADGui.ActiveDocument.resetEdit()
+            if FreeCADGui.ActiveDocument:
+                FreeCADGui.ActiveDocument.resetEdit()
             return True
     def reject(self):
         FreeCADGui.draftToolBar.isTaskOn = False
         FreeCADGui.draftToolBar.escape()
-        FreeCADGui.ActiveDocument.resetEdit()
+        if FreeCADGui.ActiveDocument:
+            FreeCADGui.ActiveDocument.resetEdit()
         return True
+    def isAllowedAlterDocument(self):
+        return False
 
 class DraftToolBar:
     "main draft Toolbar"
@@ -806,6 +810,8 @@ class DraftToolBar:
                     FreeCADGui.draftToolBar.escape()
                     FreeCADGui.ActiveDocument.resetEdit()
                     return True
+                def isAllowedAlterDocument(self):
+                    return False
             if FreeCADGui.Control.activeDialog():
                 FreeCADGui.Control.closeDialog()
             todo.delay(FreeCADGui.Control.showDialog,dummy(extra))
@@ -1438,7 +1444,8 @@ class DraftToolBar:
         if self.cancel:
             self.cancel()
             self.cancel = None
-        FreeCADGui.ActiveDocument.resetEdit()
+        if FreeCADGui.ActiveDocument:
+            FreeCADGui.ActiveDocument.resetEdit()
 
     def escape(self):
         "escapes the current command"

src/Mod/Draft/DraftTools.py

@@ -262,7 +262,11 @@ class DraftTool:
         if hasattr(FreeCADGui,"Snapper"):
             FreeCADGui.Snapper.off()
         if self.call:
-            self.view.removeEventCallback("SoEvent",self.call)
+            try:
+                self.view.removeEventCallback("SoEvent",self.call)
+            except RuntimeError:
+                # the view has been deleted already
+                pass
             self.call = None
         if self.commitList:
             todo.delayCommit(self.commitList)
@@ -492,8 +496,13 @@ class Line(Creator):
         "terminates the operation and closes the poly if asked"
         if self.obj:
             # remove temporary object, if any
-            old = self.obj.Name
-            todo.delay(self.doc.removeObject,old)
+            try:
+                old = self.obj.Name
+            except ReferenceError:
+                # object already deleted, for some reason
+                pass
+            else:
+                todo.delay(self.doc.removeObject,old)
         self.obj = None
         if self.oldWP:
             FreeCAD.DraftWorkingPlane = self.oldWP