WIP: Only fetch variants if the machine has any

cura/Machines/Models/BuildPlateModel.py

@@ -2,6 +2,7 @@ from PyQt5.QtCore import Qt
 
 from UM.Application import Application
 from UM.Qt.ListModel import ListModel
+from UM.Util import parseBool
 
 from cura.Machines.VariantManager import VariantType
 
@@ -30,6 +31,11 @@ class BuildPlateModel(ListModel):
             self.setItems([])
             return
 
+        has_variants = parseBool(global_stack.getMetaDataEntry("has_variant_buildplates", False))
+        if not has_variants:
+            self.setItems([])
+            return
+
         variant_dict = self._variant_manager.getVariantNodes(global_stack, variant_type = VariantType.BUILD_PLATE)
 
         item_list = []

cura/Machines/Models/NozzleModel.py

@@ -5,6 +5,7 @@ from PyQt5.QtCore import Qt
 
 from UM.Application import Application
 from UM.Qt.ListModel import ListModel
+from UM.Util import parseBool
 
 
 class NozzleModel(ListModel):
@@ -33,6 +34,11 @@ class NozzleModel(ListModel):
             self.setItems([])
             return
 
+        has_variants = parseBool(active_global_stack.getMetaDataEntry("has_variants", False))
+        if not has_variants:
+            self.setItems([])
+            return
+
         variant_node_dict = variant_manager.getVariantNodes(active_global_stack)
         if not variant_node_dict:
             self.setItems([])