/**
  * Creates data provider instance with search query applied
  *
  * @param array $params
  *
  * @return ActiveDataProvider
  */
 public function search($params)
 {
     $query = TicketStatus::find();
     $dataProvider = new ActiveDataProvider(['query' => $query]);
     $this->load($params);
     if (!$this->validate()) {
         // uncomment the following line if you do not want to return any records when validation fails
         // $query->where('0=1');
         return $dataProvider;
     }
     $query->andFilterWhere(['ticket_status_id' => $this->ticket_status_id, 'tstatus' => $this->tstatus]);
     return $dataProvider;
 }
    <?php 
$form = ActiveForm::begin();
?>

   

    <?php 
$ticket = Ticket::find()->all();
$listData = ArrayHelper::map($ticket, 'ticket_id', 'ticketnumber');
echo $form->field($model, 'ticket_id')->dropDownList($listData, ['prompt' => 'Select Ticket Number']);
?>

    

    <?php 
$ticket_status = TicketStatus::find()->all();
$listData = ArrayHelper::map($ticket_status, 'ticket_status_id', 'status_name');
echo $form->field($model, 'ticket_status_id')->dropDownList($listData, ['prompt' => 'Select Ticket Status']);
?>

    
   <?php 
$employee = Employee::find()->all();
$listData = ArrayHelper::map($employee, 'employee_id', 'firstname', 'lastname');
echo $form->field($model, 'employee_id')->dropDownList($listData, ['prompt' => 'Select Case Number']);
?>

    <div class="form-group">
        <?php 
echo Html::submitButton($model->isNewRecord ? 'Create' : 'Update', ['class' => $model->isNewRecord ? 'btn btn-success' : 'btn btn-primary']);
?>