Force use and update the job name with the loaded project file

CURA-4348

- If no project is loaded beforehand and then a model file is loaded,
  the job name should be determined with the current machine name and
  the first loaded model name.
- If a project is loaded, the job name should be the same as the project
  name, and it should not change until another project is loaded.

cura/CuraApplication.py

@@ -125,6 +125,8 @@ class CuraApplication(QtApplication):
     #        Cura will always show the Add Machine Dialog upon start.
     stacksValidationFinished = pyqtSignal()  # Emitted whenever a validation is finished
 
+    projectFileLoaded = pyqtSignal(str)  # Emitted whenever a project file is loaded
+
     def __init__(self):
         # this list of dir names will be used by UM to detect an old cura directory
         for dir_name in ["extruders", "machine_instances", "materials", "plugins", "quality", "user", "variants"]:

cura/PrintInformation.py

@@ -66,10 +66,11 @@ class PrintInformation(QObject):
         self._base_name = ""
         self._abbr_machine = ""
         self._job_name = ""
+        self._project_name = ""
 
         Application.getInstance().globalContainerStackChanged.connect(self._updateJobName)
         Application.getInstance().fileLoaded.connect(self.setBaseName)
-
+        Application.getInstance().projectFileLoaded.connect(self.setProjectName)
         Preferences.getInstance().preferenceChanged.connect(self._onPreferencesChanged)
 
         self._active_material_container = None
@@ -78,7 +79,6 @@ class PrintInformation(QObject):
 
         self._material_amounts = []
 
-
     # Crate cura message translations and using translation keys initialize empty time Duration object for total time
     # and time for each feature
     def initializeCuraMessagePrintTimeProperties(self):
@@ -241,6 +241,11 @@ class PrintInformation(QObject):
         self._job_name = name
         self.jobNameChanged.emit()
 
+    @pyqtSlot(str)
+    def setProjectName(self, name):
+        self._project_name = name
+        self.setJobName(name)
+
     jobNameChanged = pyqtSignal()
 
     @pyqtProperty(str, notify = jobNameChanged)
@@ -248,6 +253,11 @@ class PrintInformation(QObject):
         return self._job_name
 
     def _updateJobName(self):
+        # if the project name is set, we use the project name as the job name, so the job name should not get updated
+        # if a model file is loaded after that.
+        if self._project_name != "":
+            return
+
         if self._base_name == "":
             self._job_name = ""
             self.jobNameChanged.emit()

plugins/3MFReader/ThreeMFWorkspaceReader.py

@@ -26,6 +26,7 @@ from configparser import ConfigParser
 import zipfile
 import io
 import configparser
+import os
 
 i18n_catalog = i18nCatalog("cura")
 
@@ -876,6 +877,11 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
         nodes = self._3mf_mesh_reader.read(file_name)
         if nodes is None:
             nodes = []
+
+        base_file_name = os.path.basename(file_name)
+        if base_file_name.endswith(".curaproject.3mf"):
+            base_file_name = base_file_name[:base_file_name.rfind(".curaproject.3mf")]
+        Application.getInstance().projectFileLoaded.emit(base_file_name)
         return nodes
 
     ##  HACK: Replaces the material container in the given stack with a newly created material container.

resources/qml/OpenFilesIncludingProjectsDialog.qml

@@ -36,8 +36,6 @@ UM.Dialog
 
         var meshName = backgroundItem.getMeshName(projectFile.toString());
         backgroundItem.hasMesh(decodeURIComponent(meshName));
-        // always update the job name with the loaded project
-        PrintInformation.setBaseName(meshName);
     }
 
     function loadModelFiles(fileUrls)