Merge pull request #20193 from Ultimaker/CURA-12150-add-a-global-pref…

…erence-for-USB-printing

CURA-12150 Add local preference to monitor use of USB writing

plugins/USBPrinting/USBPrinterOutputDevice.py

@@ -97,6 +97,8 @@ def __init__(self, serial_port: str, baud_rate: Optional[int] = None) -> None:
 
         CuraApplication.getInstance().getOnExitCallbackManager().addCallback(self._checkActivePrintingUponAppExit)
 
+        CuraApplication.getInstance().getPreferences().addPreference("usb_printing/enabled", False)
+
     # This is a callback function that checks if there is any printing in progress via USB when the application tries
     # to exit. If so, it will show a confirmation before
     def _checkActivePrintingUponAppExit(self) -> None:
@@ -144,6 +146,8 @@ def requestWrite(self, nodes: List["SceneNode"], file_name: Optional[str] = None
 
         CuraApplication.getInstance().getController().setActiveStage("MonitorStage")
 
+        CuraApplication.getInstance().getPreferences().setValue("usb_printing/enabled", True)
+
         #Find the g-code to print.
         gcode_textio = StringIO()
         gcode_writer = cast(MeshWriter, PluginRegistry.getInstance().getPluginObject("GCodeWriter"))