check if the code is installed and usable (#669)

if code is imported from another user, it is not usable and thus will not be treated as an option in the ComputationalResourcesWidget. This PR checks if the code is installed and usable.

src/aiidalab_qe/app/submission/__init__.py

@@ -347,7 +347,12 @@ def _get_code_uuid(code):
 
         with self.hold_trait_notifications():
             for name, code in self.codes.items():
-                code.value = _get_code_uuid(codes.get(name))
+                # check if the code is installed and usable
+                # note: if code is imported from another user, it is not usable and thus will not be
+                # treated as an option in the ComputationalResourcesWidget.
+                code_options = [o[1] for o in self.pw_code.code_select_dropdown.options]
+                if _get_code_uuid(codes.get(name)) in code_options:
+                    code.value = _get_code_uuid(codes.get(name))
 
     def update_codes_display(self):
         """Hide code if no related property is selected."""