CURA-4525 change active build plate if that build plate does not exist anymore; disable context menu items for build plates when no selection

cura/Scene/CuraSceneController.py

@@ -41,6 +41,13 @@ class CuraSceneController(QObject):
             self._build_plate_model.setMaxBuildPlate(self._max_build_plate)
             build_plates = [{"name": "Build Plate %d" % (i + 1), "buildPlateNumber": i} for i in range(self._max_build_plate + 1)]
             self._build_plate_model.setItems(build_plates)
+            if self._active_build_plate > self._max_build_plate:
+                build_plate_number = 0
+                if self._last_selected_index >= 0:  # go to the buildplate of the item you last selected
+                    item = self._objects_model.getItem(self._last_selected_index)
+                    node = item["node"]
+                    build_plate_number = node.callDecoration("getBuildPlateNumber")
+                self.setActiveBuildPlate(build_plate_number)
             # self.buildPlateItemsChanged.emit()  # TODO: necessary after setItems?
 
     def _calcMaxBuildPlate(self):

resources/qml/Menus/ContextMenu.qml

@@ -47,6 +47,7 @@ Menu
     {
         model: Cura.BuildPlateModel
         MenuItem {
+            enabled: UM.Selection.hasSelection
             text: Cura.BuildPlateModel.getItem(index).name;
             onTriggered: CuraActions.setBuildPlateForSelection(Cura.BuildPlateModel.getItem(index).buildPlateNumber);
             checkable: true
@@ -58,6 +59,7 @@ Menu
     }
 
     MenuItem {
+        enabled: UM.Selection.hasSelection
         text: "New build plate";
         onTriggered: {
             CuraActions.setBuildPlateForSelection(Cura.BuildPlateModel.maxBuildPlate + 1);