Yii2 DepDrop Kartik widget - yii2

Question

I am trying to use the Kartik Depdrop widget. When I select the area field, the firebug console shows the data correctly like:
{"output":[{"id":"6310100000","name":"Харьков"},{"id":"6310400000","name":"Изюм"}],"selected":""}
_form.php
<?= $form->field($model, 'reg')->dropDownList(TReg::getOptions(), ['id' => 'cat-id', 'class'=>'input-large form-control']); ?>
<?= $form->field($model, 'area')->widget(DepDrop::classname(), [
'options'=>['id'=>'subcat-id', 'class'=>'input-large form-control'],
'pluginOptions'=>[
'depends'=>['cat-id'],
'placeholder'=>'Select...',
'url'=>Url::to(['/pt/subcat'])
]
]); ?>
Model
TReg.php
public static function getOptions()
{
$data=static::find()->all();
$value=(count($data)==0)? [''=>'']: \yii\helpers\ArrayHelper::map($data, 'reg_id','reg_name');
return $value;
}
Model TArea.php
public static function getAreaList($reg_id)
{
$data= static::find()->where(['reg_id' => $reg_id])->select(['area_id AS id' , 'area_name AS name'])->asArray()->all();;
$value=(count($data)==0)? [''=>'']: $data;
return $value;
}
Controller
public function actionSubcat() {
$out = [];
if (isset($_POST['depdrop_parents'])) {
$parents = $_POST['depdrop_parents'];
if ($parents != null) {
$reg_id = $parents[0];
$out = \common\models\TArea::getAreaList($reg_id);
echo Json::encode(['output' => $out , 'selected' => '']);
return;
}
}
echo Json::encode(['output' => '', 'selected' => '']);
}
What is my mistake? Thanks.