def update_dropdown_list_slot(self):
self.dropdown_widget.clear() <EOL>self.row_instance_by_index = []<EOL>for i, key in enumerate(self.row_instance_by_name.keys()):<EOL><INDENT>row_instance = self.row_instance_by_name[key]<EOL>if (row_instance.isActive()):<EOL><INDENT>self.row_instance_by_index.append(row_instance)<EOL>display_name = row_instance.getName()<EOL>self.dropdown_widget.insertItem(i, display_name)<EOL><DEDENT>row_instance.updateWidget()<EOL><DEDENT>
Keep updating the dropdown list.  Say, don't let the user choose USB devices if none is available