avoid crashing when using evaluator with no_gui
avoid crashing when using evaluator with no_gui

NicolasSchnitzler/dtk,d-tk/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk,NicolasSchnitzler/dtk,d-tk/dtk,d-tk/dtk,rdebroiz/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk,d-tk/dtk,d-tk/dtk,rdebroiz/dtk,d-tk/dtk