Searching in GridView using Radiolist

I finally got reason for this strange behaviour:

I didn’t set choice_date in public function rules. After having coded like this,everything is gonna working fine:

class MailAusgangSearch extends MailAusgang {


    public $choice_date;


    public function rules() {

        return [

            [['id', 'id_person_mitarbeiter', 'sende_fehler_code', 'angelegt_von', 'aktualisiert_von'], 'integer'],

            [['mail_antwortadresse', 'wichtigkeit', 'bodyformat', 'betreff', 'bodytext', 'freigabe_datum', 'sende_datum', 'sende_fehler_beschreibung', 'angelegt_am', 'aktualisiert_am'], 'safe'],

            [['entwurf', 'freigabe', 'gesendet','choice_date'], 'boolean'],

        ];

    }

.

.

So,this thread can be closes as succesfully solved