Wait with updating active stack variant and material until dialog was closed - CURA-4447

cura/CuraApplication.py

@@ -407,6 +407,8 @@ class CuraApplication(QtApplication):
             has_user_interaction = True
         return has_user_interaction
 
+    onDiscardOrKeepProfileChangesClosed = pyqtSignal()  # Used to notify other managers that the dialog was closed
+
     @pyqtSlot(str)
     def discardOrKeepProfileChangesClosed(self, option):
         if option == "discard":
@@ -429,6 +431,7 @@ class CuraApplication(QtApplication):
                 user_global_container.update()
 
         # notify listeners that quality has changed (after user selected discard or keep)
+        self.onDiscardOrKeepProfileChangesClosed.emit()
         self.getMachineManager().activeQualityChanged.emit()
 
     @pyqtSlot(int)

cura/Settings/MachineManager.py

@@ -47,6 +47,10 @@ class MachineManager(QObject):
         self._active_container_stack = None     # type: CuraContainerStack
         self._global_container_stack = None     # type: GlobalStack
 
+        # Used to store the new containers until after confirming the dialog
+        self._new_variant_container = None
+        self._new_material_container = None
+
         self._error_check_timer = QTimer()
         self._error_check_timer.setInterval(250)
         self._error_check_timer.setSingleShot(True)
@@ -58,6 +62,7 @@ class MachineManager(QObject):
         self._instance_container_timer.timeout.connect(self.__onInstanceContainersChanged)
 
         Application.getInstance().globalContainerStackChanged.connect(self._onGlobalContainerChanged)
+
         ##  When the global container is changed, active material probably needs to be updated.
         self.globalContainerChanged.connect(self.activeMaterialChanged)
         self.globalContainerChanged.connect(self.activeVariantChanged)
@@ -84,6 +89,9 @@ class MachineManager(QObject):
         ExtruderManager.getInstance().activeExtruderChanged.connect(self.activeStackChanged)
         self.activeStackChanged.connect(self.activeStackValueChanged)
 
+        # when a user closed dialog check if any delayed material or variant changes need to be applied
+        Application.getInstance().onDiscardOrKeepProfileChangesClosed.connect(self._executeDelayedActiveContainerStackChanges)
+
         Preferences.getInstance().addPreference("cura/active_machine", "")
 
         self._global_event_keys = set()
@@ -109,7 +117,7 @@ class MachineManager(QObject):
                                               "The selected material is incompatible with the selected machine or configuration."),
                                                 title = catalog.i18nc("@info:title", "Incompatible Material"))
 
-    globalContainerChanged = pyqtSignal() # Emitted whenever the global stack is changed (ie: when changing between printers, changing a global profile, but not when changing a value)
+    globalContainerChanged = pyqtSignal()  # Emitted whenever the global stack is changed (ie: when changing between printers, changing a global profile, but not when changing a value)
     activeMaterialChanged = pyqtSignal()
     activeVariantChanged = pyqtSignal()
     activeQualityChanged = pyqtSignal()
@@ -747,7 +755,7 @@ class MachineManager(QObject):
             self.blurSettings.emit()
             old_material.nameChanged.disconnect(self._onMaterialNameChanged)
 
-            self._active_container_stack.material = material_container
+            self._new_material_container = material_container   # self._active_container_stack will be updated with a delay
             Logger.log("d", "Active material changed")
 
             material_container.nameChanged.connect(self._onMaterialNameChanged)
@@ -801,13 +809,13 @@ class MachineManager(QObject):
             old_material = self._active_container_stack.material
             if old_variant:
                 self.blurSettings.emit()
-                self._active_container_stack.variant = containers[0]
+                self._new_variant_container = containers[0]  # self._active_container_stack will be updated with a delay
                 Logger.log("d", "Active variant changed to {active_variant_id}".format(active_variant_id = containers[0].getId()))
                 preferred_material_name = None
                 if old_material:
                     preferred_material_name = old_material.getName()
-
-                self.setActiveMaterial(self._updateMaterialContainer(self._global_container_stack.getBottom(), self._global_container_stack, containers[0], preferred_material_name).id)
+                preferred_material_id = self._updateMaterialContainer(self._global_container_stack.getBottom(), self._global_container_stack, containers[0], preferred_material_name).id
+                self.setActiveMaterial(preferred_material_id)
             else:
                 Logger.log("w", "While trying to set the active variant, no variant was found to replace.")
 
@@ -871,7 +879,20 @@ class MachineManager(QObject):
                     setting_info["stack"].sendPostponedEmits()
 
             if not has_user_interaction:
-                    self.activeQualityChanged.emit()
+                self.activeQualityChanged.emit()
+
+    ##  Used to update material and variant in the active container stack with a delay.
+    #   This delay prevents the stack from triggering a lot of signals (eventually resulting in slicing)
+    #   before the user decided to keep or discard any of their changes using the dialog.
+    #   The activeQualityChanged signal triggers this method.
+    def _executeDelayedActiveContainerStackChanges(self):
+        if self._new_material_container is not None:
+            self._active_container_stack.material = self._new_material_container
+            self._new_material_container = None
+
+        if self._new_variant_container is not None:
+            self._active_container_stack.variant = self._new_variant_container
+            self._new_variant_container = None
 
     ##  Determine the quality and quality changes settings for the current machine for a quality name.
     #