Filtering data using ajax observefield - cakephp

Question

I ve tried to implemented filtering data (list base on selected category) using dropdown with observefield and ajax pagination. I use session to remember selected category in order to keep pagination.
Here is my code (Cakephp 1.2)
In view :
echo $form->select('Category.id', $categories, null, array('id' => 'categories'),'Filter by Categories')
echo $ajax->observeField('categories' ,array('url' =>'update_category','update' => 'collectionDiv'));
In Controller:
if(!empty($this->data['Category']['id']))
{
$cat_id=$this->data['Category']['id'];
$filters=array('Collection.category_id' => $cat_id);
$this->set('collections', $this->paginate('Collection', $filters));
$this->Session->write($this->name.'.$cat_id', $category_id);
}
else
{
$cat_id=$this->Session->read($this->name.'.cat_id');
$filters=array('Collection.category_id' => $cat_id);
$this->set('collections', $this->paginate('Collection'));
}
The filter work as I wanted but the problem is when I select empty value('Filter by Category) it still remember last category session so I can't back to the default list (All record list without filter).
I've tried to make some condition but still not success. Is there another way? Please I appreciate your help. thank
hermawan

Answer 1

Perhaps I don't understand the question, but it looks to me like it might be worth changing:
else
{
$cat_id=$this->Session->read($this->name.'.cat_id');
$filters=array('Collection.category_id' => $cat_id);
$this->set('collections', $this->paginate('Collection'));
}
to:
else
{
$this->set('collections', $this->paginate('Collection',array()));
}
In effect your code appears to be doing this anyway. Check what the URL is at the top of the browser window after it has returned. Does it still contain pagination directives from the previous query?
You might want to review http://book.cakephp.org/view/167/AJAX-Pagination and make sure you've 'ticked all the boxes'.

Answer 2

I got it, It work as I hope now. I my self explain the condition and solution.
When I select category from combobox, then it render the page the code is :
If ($this->data['Category']['id']) {
$cat_id=$this->data['Category']['id'];
$this->Session->write($this->name.'.category_id', $category_id);
// I will use this session next when I click page number
$filters=array('Collection.art_type_id' => $category_id);
$this->set('collections', $this->paginate('Collection', $filters));
}else{
//if clik page number, next or whatever, $this->data['Category']['id'] will empty so
// use session to remember the category so the page will display next page or prev
// page with the proper category, But the problem is, when I set category fillter to
// "All Category" it will dislpay last category taked from the session. To prevent it
// I used $this->passedArgs['page']. When I clik the page paginator it will return
// current number page, but it will be empty if we click dropdown.
if (!empty($this->passedArgs['page']) {
$cat_id=$this->Session->read($this->name.'.category_id');
$filters=array('Collection.category_id' => $cat_id);
$this->set('collections', $this->paginate('Collection',$filters));
}else{
$this->set('collections', $this->paginate('Collection'));
}
}
From this case, I think that observefield will not send passedArg as we get from url such from ajax link or html->link. I hope this will usefull to anybody