TYPO3 form validation not working if only radio buttons are used -

i have trouble multistep form because validation single step contains form radio buttons not working :(

i have simple property type represent radio button value:

class step1data extends \typo3\cms\extbase\domainobject\abstractentity {  /**  * type  *   * @var string  * @validate notempty  */ protected $type;  /**  * returns type  *   * @return string $type  */ public function gettype() {     return $this->type; }  /**  * sets type  *   * @param string $type  * @return void  */ public function settype($type) {     $this->type = $type; }  } 

the fluid mark-up looks follows step:

<f:layout name="default" /> <f:section name="main">     <f:form action="step1redirect" class="step1" name="step1data" object="{step1data}">          <f:render partial="formerrors" arguments="{field: 'step1data.type'}" />          <label>             <f:form.radio property="type" value="type-1" />             type 1          </label>          <label>             <f:form.radio property="type" value="type-2" />             type 2          </label>          <f:form.submit value="next" />                </f:form> </f:section> 

the controller actions step are:

/**  * step1  *  * @param \fox\example\domain\model\step1data $step1data  * @ignorevalidation $step1data  */ public function step1action(\fox\example\domain\model\step1data $step1data = null) {      if ($globals['tsfe']->fe_user->getkey('ses', 'step1data') && $step1data == null) {         $step1data = unserialize($globals['tsfe']->fe_user->getkey('ses', 'step1data'));     }      $this->view->assign('step1data', $step1data);  }  /**  * step1 redirect action  *  * @param \fox\example\domain\model\step1data $step1data  */ public function step1redirectaction(\fox\example\domain\model\step1data $step1data) {      $globals['tsfe']->fe_user->setkey('ses', 'step1data', serialize($step1data));     $globals['tsfe']->fe_user->storesessiondata();      $this->redirect('step2');  } 

if add example second property name of type string notempty annotation , fluid textfield form like:

<f:layout name="default" /> <f:section name="main">     <f:form action="step1redirect" class="step1" name="step1data" object="{step1data}">          <f:render partial="formerrors" arguments="{field: 'step1data.type'}" />          <label>             <f:form.radio property="type" value="type-1" />             type 1          </label>          <label>             <f:form.radio property="type" value="type-2" />             type 2          </label>           <!-- example second property -->          <f:render partial="formerrors" arguments="{field: 'step1data.name'}"/>            <f:form.textfield property="name" />          <!-- example second property -->           <f:form.submit value="next" />                </f:form> </f:section> 

the validation working. validation works if have textfield on form, if have radio buttons without textfield on form validation not working , error appears because step1data object null.

i don't know reason weird problem, hope can me?

the solution hidden input field above radio buttons same property name:

    <f:form.hidden property="type" />     <div class="group-block">         <label>             <f:form.radio property="type" value="wish1" />             type1         </label>     </div>     <div class="group-block">         <label>             <f:form.radio property="type" value="wish2" />             type2         </label>     </div> 

so firstly hidden field checked , validated , if radio button checked type property overwritten