Update GetObjectDialog to use object_only parameter in get_current_item_id method

Author: PierreRaybaut

CHANGELOG.md

@@ -42,6 +42,8 @@ This release requires PlotPy v2.4.0 or later, which brings the following bug fix
 
 * Progress bar is now automatically closed as expected when an error occurrs during a long operation (e.g. when opening a file)
 
+* Difference, division, ...: dialog box for the second operand selection was allowing to select a group (only a signal or an image should be selected)
+
 ## DataLab Version 0.16.1 ##
 
 Since version 0.16.0, many validation functions have been added to the test suite.

cdl/core/gui/objectview.py

@@ -286,7 +286,7 @@ def __init__(
 
     def __current_object_changed(self) -> None:
         """Item selection has changed"""
-        self.__current_object_uuid = self.tree.get_current_item_id()
+        self.__current_object_uuid = self.tree.get_current_item_id(object_only=True)
         self.ok_btn.setEnabled(bool(self.__current_object_uuid))
 
     def get_current_object_uuid(self) -> str: