如何在cakephp中对generateTreeList（）方法的结果进行分页？

Question

i have a Categories table in my database that has lft, rght and parent_id columns for using Tree behavior in Cakephp. the problem is how to paginate result of generateTreeList() method?

i can't use this : i want to paginate it

      $categories = $this->Category->generateTreeList(null,null,null,'_');
      $this->set('categories', $categories);

i also try to use thread type of find method, for retrieving data and use some recursive helper function like below for generating tree data

function CategoryRecTable($resultOfFindThread, $i = null) {
        $i = $i . '-';
        if (count($array)) {
            foreach ($resultOfFindThread as $vals) {
                echo "<tr>
                <td><font color=\"#CCCCCC\">" . $i . "</font>" . $vals['Category']['category'] . "</td>
                <td>" . 
                $this->Html->link('down' , array('admin' => false, 'controller' => 'categories', 'action' => 'movedown', $vals['Category']['id'])) . " - " . 
                $this->Html->link('up', array('admin' => false, 'controller' => 'categories', 'action' => 'moveup', $vals['Category']['id'])) . "</td>
                <td>Page</td>
                <td>" .  $vals['Category']['category'] . "</td>
                <td>" . $vals['Category']['id'] . "</td>
                <td>" . $this->Html->Link('Edit', array('controller' => 'ategories', 'action' => 'edit', $vals['Category']['id'])) . "</td>
                <td>" . $this->Html->Link(
                        'Delete',
                        array('admin' => true, 'action' => 'delete', $vals['Category']['id']),
                        array('confirm' => 'Are you sure?')) . "</td></tr>\n"; 
                if (count($vals['children'])) {
                    $this->CategoryRecTable($vals['children'], $i);
                }
                echo "\n";
            }
            echo "\n";
        }
    }

but also my problem exist, how to paginate this data in Cakephp. anybody can help me? thanks a lot

Answer 1

I'm not sure if this is possible as generateTreeList does not except parameters for LIMIT. There may be a way to hack it via extension of the Tree behaviour but this is not something I would recommend for usability and productivity purposes.

Instead, I would use a library such as jsTree: http://www.jstree.com/ .

You can make similar performance gains that you'd receive from pagination by loading a sub-tree using ajax. It's far more intuitive and will fit on one page.

This style interface will also allow you to rearrange your category tree too. For example, it will allow you to implement functionality move a sub-category up to a top-level category and vice-versa.

This solution will be a lot easier to implement than hacking pagination on generate tree list.

Answer 2

put and order on lft field with

$this->Paginator->settings = array('order'=>'Category.lft');

and then you can use $this->Category->formatTreeList to change category names with spaced version.