cakephp: extend a model class to override pagination methods

i spent the last 2 days looking for a solution for a problem with pagination in cakephp.

In short, i need diferent pagination methods for the same model. The index action will use the default method and the view action will use the method with a custom query.

Based on the OOP's inheritance concept, i thought that the solution was to extend my model and override the pagination method on the extended model. So, i can call from the controller the default pagination method for the index action and the custom methods for the view action.

The question is: how can i extend my model class? Will work this ideia?

this is my model:

<?php
class Communication extends AppModel {

var $name = 'Communication';
var $displayField = 'title';

//The Associations below have been created with all possible keys, those that are not needed can be removed

var $hasMany = array(
    'Interaction' => array(
        'className' => 'Interaction',
        'foreignKey' => 'communication_id',
        'dependent' => false,
        'conditions' => '',
        'fields' => '',
        'order' => '',
        'limit' => '',
        'offset' => '',
        'exclusive' => '',
        'finderQuery' => '',
        'counterQuery' => ''
    ),
    'Star' => array(
        'className' => 'Star',
        'foreignKey' => 'communication_id',
        'dependent' => false,
        'conditions' => '',
        'fields' => '',
        'order' => '',
        'limit' => '',
        'offset' => '',
        'exclusive' => '',
        'finderQuery' => '',
        'counterQuery' => ''
    )
);

var $hasAndBelongsToMany = array(
    'Document' => array(
        'className' => 'Document',
        'joinTable' => 'communications_documents',
        'foreignKey' => 'communication_id',
        'associationForeignKey' => 'document_id',
        'unique' => true,
        'conditions' => '',
        'fields' => '',
        'order' => '',
        'limit' => '',
        'offset' => '',
        'finderQuery' => '',
        'deleteQuery' => '',
        'insertQuery' => ''
    ),
    'Event' => array(
        'className' => 'Event',
        'joinTable' => 'communications_events',
        'foreignKey' => 'communication_id',
        'associationForeignKey' => 'event_id',
        'unique' => true,
        'conditions' => '',
        'fields' => '',
        'order' => '',
        'limit' => '',
        'offset' => '',
        'finderQuery' => '',
        'deleteQuery' => '',
        'insertQuery' => ''
    ),
    'Meeting' => array(
        'className' => 'Meeting',
        'joinTable' => 'communications_meetings',
        'foreignKey' => 'communication_id',
        'associationForeignKey' => 'meeting_id',
        'unique' => true,
        'conditions' => '',
        'fields' => '',
        'order' => 'date_create DESC',
        'limit' => '',
        'offset' => '',
        'finderQuery' => '',
        'deleteQuery' => '',
        'insertQuery' => ''
    ),
    'User' => array(
        'className' => 'User',
        'joinTable' => 'communications_users',
        'foreignKey' => 'communication_id',
        'associationForeignKey' => 'user_id',
        'unique' => true,
        'conditions' => '',
        'fields' => '',
        'order' => 'name',
        'limit' => '',
        'offset' => '',
        'finderQuery' => '',
        'deleteQuery' => '',
        'insertQuery' => ''
    )
);

function getComInfos($id) {

    $this->unbindModel(array('hasAndBelongsToMany'=>array('Document','Event','Meeting')));
    $this->unbindModel(array('hasMany'=>array('Star','Interaction')));
    $communication_infos = $this->read(null, $id);

    //debug($communication_infos);

    return $communication_infos;

}

function getComLinks($id) {

    $communication_links = $this->query("
    SELECT 'documents' AS 'type', 'D' AS 'marker', d.id AS id, d.date_create AS date, du.user_id AS info_aux, d.title AS title, d.desc AS content 
    FROM communications_documents AS cd
    JOIN documents AS d ON d.id = cd.document_id
    JOIN documents_users AS du ON du.document_id = d.id
    WHERE cd.communication_id = ".$id."

    UNION

    SELECT 'events' AS 'type', 'E' AS 'marker', e.id AS id, e.date_create AS date, e.institution AS info_aux, e.title AS title, e.desc AS content
    FROM communications_events AS ce
    JOIN events AS e ON e.id = ce.event_id
    WHERE ce.communication_id =".$id."

    UNION

    SELECT 'meetings' AS 'type', 'R' AS 'marker', m.id AS id, m.date_create AS date, m.site AS info_aux, m.title AS title, m.desc AS content
    FROM communications_meetings AS cm
    JOIN meetings AS m ON m.id = cm.meeting_id
    WHERE cm.communication_id =".$id."

    UNION

    SELECT 'interactions' AS 'type', 'C' AS 'marker', i.id AS id, i.date_create AS date, i.user_id AS info_aux, i.title AS title, i.content AS content
    FROM interactions AS i
    WHERE i.communication_id =".$id."

    ORDER BY date DESC
    ");

    //debug($communication_links);

    return $communication_links;

}

}

And this is my two custom pagination method, that i need to use just to the view action:

function paginate($conditions, $fields, $order, $limit, $page = 1, $recursive = null, $extra = array()) {

    $recursive = -1;
    return $this->query("
    SELECT 'documents' AS 'type', 'D' AS 'marker', d.id AS id, d.date_create AS date, du.user_id AS info_aux, d.title AS title, d.desc AS content 
    FROM communications_documents AS cd
    JOIN documents AS d ON d.id = cd.document_id
    JOIN documents_users AS du ON du.document_id = d.id
    WHERE cd.communication_id = 137

    UNION

    SELECT 'events' AS 'type', 'E' AS 'marker', e.id AS id, e.date_create AS date, e.institution AS info_aux, e.title AS title, e.desc AS content
    FROM communications_events AS ce
    JOIN events AS e ON e.id = ce.event_id
    WHERE ce.communication_id =137

    UNION

    SELECT 'meetings' AS 'type', 'R' AS 'marker', m.id AS id, m.date_create AS date, m.site AS info_aux, m.title AS title, m.desc AS content
    FROM communications_meetings AS cm
    JOIN meetings AS m ON m.id = cm.meeting_id
    WHERE cm.communication_id = 137

    UNION

    SELECT 'interactions' AS 'type', 'C' AS 'marker', i.id AS id, i.date_create AS date, i.user_id AS info_aux, i.title AS title, i.content AS content
    FROM interactions AS i
    WHERE i.communication_id = 137

    ORDER BY date DESC
    LIMIT ".(($page-1)*$limit).", ".$limit);

}

function paginateCount($conditions = null, $recursive = 0, $extra = array()) {
    $sql = "
    SELECT 'documents' AS 'type', 'D' AS 'marker', d.id AS id, d.date_create AS date, du.user_id AS info_aux, d.title AS title, d.desc AS content 
    FROM communications_documents AS cd
    JOIN documents AS d ON d.id = cd.document_id
    JOIN documents_users AS du ON du.document_id = d.id
    WHERE cd.communication_id = 137

    UNION

    SELECT 'events' AS 'type', 'E' AS 'marker', e.id AS id, e.date_create AS date, e.institution AS info_aux, e.title AS title, e.desc AS content
    FROM communications_events AS ce
    JOIN events AS e ON e.id = ce.event_id
    WHERE ce.communication_id = 137

    UNION

    SELECT 'meetings' AS 'type', 'R' AS 'marker', m.id AS开发者_开发百科 id, m.date_create AS date, m.site AS info_aux, m.title AS title, m.desc AS content
    FROM communications_meetings AS cm
    JOIN meetings AS m ON m.id = cm.meeting_id
    WHERE cm.communication_id = 137

    UNION

    SELECT 'interactions' AS 'type', 'C' AS 'marker', i.id AS id, i.date_create AS date, i.user_id AS info_aux, i.title AS title, i.content AS content
    FROM interactions AS i
    WHERE i.communication_id = 137

    ORDER BY date DESC
    ";
    $this->recursive = $recursive;
    $results = $this->query($sql);
    return count($results);
}`

In the controller, I would set some very general options for each model, like so:

    class SampleController extends AppController {
        ...
        var $paginate = array(
            'ModelName' => array( ...general options... )
        );
        ...
    }

And then inside each action, you can customize it:

    ...
    function index(){
        $this->paginate = array(
            ... specific pagination options for index action ...
        );
        $this->paginate('ModelName');
    }
    ...
    function view(){
        $this->paginate = array(
            ... specific pagination options for view action ...
        );
        $this->paginate('ModelName');
    }

This way you can have custom pagination results for each action.

Hope that helps.