BIM: fix BimMaterial dialog regression

Fixes #24381

src/Mod/BIM/bimcommands/BimMaterial.py

@@ -76,7 +76,6 @@ class BIM_Material:
             self.dlg.raise_()
             return
 
-        self.dlg = None
         self.dlg = QtGui.QDialog()
         self.dlg.objects = [
             obj
@@ -195,6 +194,7 @@ class BIM_Material:
             context4.triggered.connect(self.onDelete)
 
             # other signal/slots to connect
+            self.dlg.rejected.connect(self.onReject)
             matList.customContextMenuRequested.connect(self.onRightClick)
             matList.itemDoubleClicked.connect(self.onAccept)
             matList.itemChanged.connect(self.onEndRename)
@@ -204,7 +204,7 @@ class BIM_Material:
 
         else:
             # no material in the document
-            self.dlg = None
+            self.onReject()
             FreeCADGui.runCommand("Arch_Material")
 
     def onRightClick(self, pos):
@@ -430,14 +430,12 @@ class BIM_Material:
                         self.rescan()
 
     def onCreate(self):
-        if self.dlg:
-            self.dlg.hide()
-            FreeCADGui.runCommand("Arch_Material")
+        self.onReject()
+        FreeCADGui.runCommand("Arch_Material")
 
     def onMulti(self):
-        if self.dlg:
-            self.dlg.hide()
-            FreeCADGui.runCommand("Arch_MultiMaterial")
+        self.onReject()
+        FreeCADGui.runCommand("Arch_MultiMaterial")
 
     def onAccept(self, item=None):
         if self.dlg:
@@ -458,13 +456,14 @@ class BIM_Material:
             p = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/BIM")
             p.SetInt("BimMaterialDialogWidth", self.dlg.width())
             p.SetInt("BimMaterialDialogHeight", self.dlg.height())
-            return self.onReject()
+        from DraftGui import todo
+        # delay required for matList.itemDoubleClicked action
+        todo.delay(self.onReject, None)
 
     def onReject(self):
-        if getattr(self, "dlg", None):
+        if self.dlg:
             self.dlg.hide()
-            del self.dlg
-        return True
+            self.dlg = None
 
     def onUpArrow(self):
         if self.dlg: