Fixes for resetting print time information when removing all or last model, reduce signals being used for print time resetting - CURA-4852

cura/CuraActions.py

@@ -94,6 +94,10 @@ class CuraActions(QObject):
                     removed_group_nodes.append(group_node)
                     op.addOperation(SetParentOperation(remaining_nodes_in_group[0], group_node.getParent()))
                     op.addOperation(RemoveSceneNodeOperation(group_node))
+
+            # Reset the print information
+            Application.getInstance().getController().getScene().sceneChanged.emit(node)
+
         op.push()
 
     ##  Set the extruder that should be used to print the selection.

cura/CuraApplication.py

@@ -1066,12 +1066,12 @@ class CuraApplication(QtApplication):
             for node in nodes:
                 op.addOperation(RemoveSceneNodeOperation(node))
 
+                # Reset the print information
+                self.getController().getScene().sceneChanged.emit(node)
+
             op.push()
             Selection.clear()
 
-        # Reset the print information:
-        self.getController().getScene().sceneChanged.emit(node)
-
     ## Reset all translation on nodes with mesh data.
     @pyqtSlot()
     def resetAllTranslation(self):

cura/PrintInformation.py

@@ -8,7 +8,9 @@ from UM.Application import Application
 from UM.Logger import Logger
 from UM.Qt.Duration import Duration
 from UM.Preferences import Preferences
+from UM.Scene.SceneNode import SceneNode
 from UM.Settings.ContainerRegistry import ContainerRegistry
+from cura.Scene.CuraSceneNode import CuraSceneNode
 
 from cura.Settings.ExtruderManager import ExtruderManager
 from typing import Dict
@@ -65,7 +67,7 @@ class PrintInformation(QObject):
         self._backend = Application.getInstance().getBackend()
         if self._backend:
             self._backend.printDurationMessage.connect(self._onPrintDurationMessage)
-        Application.getInstance().getController().getScene().sceneChanged.connect(self.setToZeroPrintInformation)
+        Application.getInstance().getController().getScene().sceneChanged.connect(self._onSceneChanged)
 
         self._base_name = ""
         self._abbr_machine = ""
@@ -395,12 +397,25 @@ class PrintInformation(QObject):
         return result
 
     # Simulate message with zero time duration
-    def setToZeroPrintInformation(self, build_plate_number):
+    def setToZeroPrintInformation(self, build_plate):
-        temp_message = {}
-        if build_plate_number not in self._print_time_message_values:
-            self._print_time_message_values[build_plate_number] = {}
-        for key in self._print_time_message_values[build_plate_number].keys():
-            temp_message[key] = 0
 
+        # Construct the 0-time message
+        temp_message = {}
+        if build_plate not in self._print_time_message_values:
+            self._print_time_message_values[build_plate] = {}
+        for key in self._print_time_message_values[build_plate].keys():
+            temp_message[key] = 0
         temp_material_amounts = [0]
-        self._onPrintDurationMessage(build_plate_number, temp_message, temp_material_amounts)
+
+        self._onPrintDurationMessage(build_plate, temp_message, temp_material_amounts)
+
+    ##  Listen to scene changes to check if we need to reset the print information
+    def _onSceneChanged(self, scene_node):
+
+        # Ignore any changes that are not related to sliceable objects
+        if not isinstance(scene_node, SceneNode)\
+                or not scene_node.callDecoration("isSliceable")\
+                or not scene_node.callDecoration("getBuildPlateNumber") == self._active_build_plate:
+            return
+
+        self.setToZeroPrintInformation(self._active_build_plate)