Update multilingual content with AJAX in Yii - ajax

Question

Refer to my code below, when user click on en button, the content will be changed to English, while clicking tw button, the content will be changed to Chinese.
However, the page will be refreshed each time when user click either en or tw button. I want to ask how can I implement AJAX content update in this case?
The result is when user click either en or tw button, the page won't be refreshed to change the content language.
Thanks
I have refer to Yii docs here, but seem that it is not appropriate for my case
C:\wamp\www\website\protected\views\site\index.php
<?php
$lang = isset($_GET["lang"]) ? $_GET["lang"] : "en_uk";
$lang = $lang == "en" ? "en_uk" : "zh_tw";
Yii::app()->setLanguage($lang);
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="get">
<input type="submit" value="en" name="lang" />
<input type="submit" value="tw" name="lang" />
</form>
<div class="main">
<?php echo Yii::t(Yii::app()->controller->id, "Causeway Bay"); ?>
</div>

Answer 1

Best practice is to reload the page in these cases, because usually you have to update so much, that it is just not worth it.
That said, CHtml's ajaxSubmitButton is the cleanest way to implement this, because you can map every event of your call very easily. It looks something like this:
<?php
echo CHtml::ajaxSubmitButton('en', CHtml::normalizeUrl(array('site/changeLanguage')),
array(
'error'=>'js:function(){
alert("error");
}',
//if you add a return false in this, it will not submit.
'beforeSend'=>'js:function(){
alert("beforeSend");
}',
'success'=>'js:function(data){
alert("success, data from server: "+data);
}',
'complete'=>'js:function(){
alert("complete");
}',
//'update'=>'#where_to_put_the_response',
)
);
?>
You don't have to use every parameter of course. The update parameter can update a HTML tag instantly.
EDIT:
This can be done easily if you use the controller's renderPartial method, for instance in your site controller if you have the action responsible for the index.
public function actionIndex(){
//get variables, etc
if(Yii::app()->request->isAjaxRequest) {
$lang = $_POST['nameOfSubmit'];
}else {
//...
}
//if the 3rd parameter is true, the method returns the generated HTML to a variable
$page = $this->renderPartial('_page', array(/*parameters*/ ), true);
echo $page;
}
And then, in your view file you can simply have
<?php echo CHtml::ajaxSubmitButton('en', CHtml::normalizeUrl(array('site/index')),
array('update'=>'#content_div',));?>
and
<?php echo CHtml::ajaxSubmitButton('tw', CHtml::normalizeUrl(array('site/index')),
array('update'=>'#content_div',));?>