Yii - 如何以相同的形式保存两个模型？

I am working on a project. I want to save 2 models in a same form. I've tried like this: actionCreate in QController.php

public function actionCreate()
{
    $model=new Question;
    $test=new Answer;

    if(isset($_POST['Question']) && ($_POST['Answer']))
    {
        $model->attributes=$_POST['Question'];
        $model->question=CUploadedFile::getInstance($model,'question');
        $test->attributes=$_POST['Answer'];
        $valid=$model->validate();
        $valid=$test->validate() && $valid;
        if($valid){
            $model->save(false);
            $test->save(false);
            $model->question->saveAs(Yii::app()->basePath . '/../images/questions/' . $model->question.'');
            $this->redirect(array('view','id'=>$model->id_question));
        }
     }

   $this->render('create',array(
         'model'=>$model,
         'test'=>$test,
   ));
}

Then, in my Q/_form.php

<?php $form=$this->beginWidget('bootstrap.widgets.TbActiveForm',array(
'id'=>'question-form',
'enableAjaxValidation'=>false,
)); ?>

<?php $answerModel = new Answer; ?>


<p class="help-block">Fields with <span class="required">*</span> are required.</p>

<?php echo $form->errorSummary($model, $answerModel); ?>

<?php echo $form->fileFieldRow($model,'question',array('class'=>'span5','maxlength'=>50)); ?>

<?php echo $form->textFieldRow($answerModel,'optionA',array('class'=>'span5','maxlength'=>100)); ?>

//rest of codes

<?php $this->endWidget(); ?>

I've tried this but still not save the data. How can I do to fix it? Thanks for your answer

You should validate first and then save data:

$model->attributes=$_POST['Question'];
$test->attributes=$_POST['Answer'];

$valid = $model->validate();
$valid = $location->validate() && $valid;

if ($valid) {
    // use false parameter to disable validation
    $model->save(false);
    $test->save(false);

    // redirect
}

And with transactions:

$model->attributes=$_POST['Question'];
$test->attributes=$_POST['Answer'];

$valid = $model->validate();
$valid = $location->validate() && $valid;

if ($valid) {
    $dbTransaction = Yii::app()->db->beginTransaction();
    try {
        // use false parameter to disable validation
        $model->save(false);
        $test->save(false);
        $dbTransaction->commit();

        // redirect here
    } catch (Exception $e) {
        $dbTransaction->rollBack();

        // save/process error
    } 
 }