php - Yii - How To Show Other Property Not Its ID -

i have related tables on database picture below:

then, have page view file picture below:

i want show username, not it's id. here code in view/file/_view.php

<div class="view">      <b><?php echo chtml::encode($data->getattributelabel('id_file')); ?>:</b> <?php echo chtml::link(chtml::encode($data->id_file),array('view','id'=>$data->id_file)); ?> <br />  <b><?php echo chtml::encode($data->getattributelabel('nama_file')); ?>:</b> <?php echo chtml::encode($data->nama_file); ?> <br />  <b><?php echo chtml::encode($data->getattributelabel('deskripsi')); ?>:</b> <?php echo chtml::encode($data->deskripsi); ?> <br />  <b><?php echo chtml::encode($data->getattributelabel('id_user')); ?>:</b> <?php echo chtml::encode($data->id_user); ?> <br />  <b><?php echo chtml::encode($data->getattributelabel('id_kategori')); ?>:</b> <?php echo chtml::encode($data->id_kategori); ?> <br />  <b><?php echo chtml::encode($data->getattributelabel('tgl_post')); ?>:</b> <?php echo chtml::encode($data->tgl_post); ?> <br />  <hr /> </div> 

filecontroller.php

public function actionview($id) {     $this->render('view',array(         'model'=>$this->loadmodel($id),     )); } 

index.php output _view.php

<?php     $this->breadcrumbs=array( 'files',     );  ?>  <h1>files</h1>  <?php $this->widget('bootstrap.widgets.tblistview',array(     'dataprovider'=>$dataprovider,     'itemview'=>'_view', )); ?> 

can me change it? lot. p.s.: sorry bad english

first need have relation user table in model, assume have since have fks on pic above. lets assume relation "user" , in user table field want display "username".

you should replace: php <?php echo chtml::encode($data->id_user); ?>

with: php <?php echo chtml::encode($data->user->username); ?>