Флаттер не сценкус текстовый поле
FocusScope.of(context).unfocus();
Helpful Hare
FocusScope.of(context).unfocus();FocusScopeNode currentFocus = FocusScope.of(context);
if (!currentFocus.hasPrimaryFocus) {
currentFocus.unfocus();
}FocusScope.of(context).unfocus();
_textEditingController.clear();