Edit: Disregard the above, I totally missed the point.

You can't directly pass an object or an array to the view using tags. What you have to do is define more nested tags. For example, if you have an array called "car" with two keys, "color" and "year", you would have to create 3 tags: car, car_color and car_year. The first one should set a local variable for your car and expand the tag; while the other ones should return the corresponding keys of the local car variable. I can't write a code example right now but I hope this much can help you.

My problem now is that I don't know how to pass an object (or an array) to the tag.

I.e.

1. Inside my users tag I define an object called $output which consists of two arrays.

public  function users(FTL_Binding $tag)
{    
....
$output = $ci->my_crud->render();
$tag->locals->output_tag = $output;
$tag->expand();
}

2.I define the output_tag which should return the $output object

public static function output_tag(FTL_Binding $tag) {
      
        return isset($tag->locals->output_tag) ? $tag->locals->output_tag : '';
}

3. I call the output_tag inside my view :

<ion:users>
    <ion:output_tag/>
</ion:users>

I get the following error :
A PHP Error was encountered
Severity: 4096
Message: Object of class stdClass could not be converted to string
Filename: ftl/parser.php
Line Number: 159

Can you help me pass the object in the view via tag ?

Furthermore, I would like to ask if I can call the helper functions inside the tags i.e.:

$ci =  &get_instance();
$ci->load->helper('form');
$ci->load->library('form_validation');

And after the above, to actually perform the validations:

$ci->form_validation->set_rules('album_name', 'Album Name', 'required');
$ci->form_validation->set_rules('description', 'Album Description', 'required');
$ci->form_validation->set_rules('privacy', 'privacy', 'required');
$ci->form_validation->set_rules('private_code', 'Private Code', 'required');

Is it possible and and good in terms of design ?

1. Assuming you've already created your $private_code, add that to your $tag variable locals in your index function before expanding the tag:

...
$tag->locals->private_code = $private_code;
$tag_expand();
...

2. Create a function to return your private code to your view:

public static function private_code(FTL_Binding $tag) {
   return isset($tag->locals->private_code) ? $tag->locals->private_code : '';
}

3. Include the tag in your view:

<ion:photo_album>
     <p>My private code is <ion:private_code />!</p>
     <ion:title />
</ion:photo_album>

Inside tags.php :

 public static function index(FTL_Binding $tag)
    {
        // Get the module URI
        include APPPATH . 'config/modules.php';

        $uri = array_search('Photoalbums', $modules);
        
        $tag->expand();
            
        return $tag->parse_as_nested(file_get_contents(MODPATH.'Photoalbums/views/photoalbums/create'.EXT));
    } 

The problem is that i want to pass a variable from the controller to the"create" view (i.e. $private_code_element). How can I do it ?

On plain CodeIgniter I was using it as follows:
controller

 $data_to_view['private_code_element'] = $private_code;  
$this->load->view('photoalbums/create',$data_to_view); 

What I still haven't found is how to link the modules, that I've created, to a page inside my theme. I.e.I have created a Module (Name: "Photo_albums Module", URI: "photo_albums") and would like to display the content inside my ionize theme's page. Is that possible ?

I've managed to create new modules following the Demo module and the "http://ionizecms.com/en/news/ionize-creating-a-module" howto guide.

Another question: Do I need to define all my custom db tables to the "config.xml" of the newly created module?

The next step is to load the custom modules to my existing theme.

I'm new to codeigniter and so far find it extremely usefull for creating web apps. I have created several controllers, models and views in codeigniter but came at a point where a cms was needed in order to create a three level administration menu.

Ionize CMS is perfect for what I need but I have a basic (rookie) question : How do I migate the controllers, the models and the views that I created on Codeigniter to Ionize installation ? Is a simple copy paste from CI to Ionize enough ?