[Ed B.]

First of all, here is what I would like to achieve. The module I am working on is for X-cart 5.3.6.0. We sell books, and we would like
to have a page of an author, where we have the name, photo, description of the author
(this part has been done), and all his books underneath. As I wrote in the thread,

https://forum.x-cart.com/showthread.php?t=77082 I made a model for entities "Author" in ManyToMany relationship with the model Product.


I have following files to output the page


Controller file Controller/Customer/Author.php with

class Author extends \XLite\Controller\Customer\ACustomer
{
 protected $params = array('target', 'author_id');

 public function getAuthorId()
 {
     return \XLite\Core\Request::getInstance()->author_id ?: 0;
    }
}

so that the page can be called with author_id,
page viewer file View/Page/Customer/Author.php (basically a modification of

View/Page/Customer/Category.php )

<?php

namespace XLite\Module\EdB\Librairie\View\Page\Customer;
use \XLite\Core\Database;
use \Model\Catalog\Base;
/**
 * Category widget
 *
 * @ListChild (list="center", zone="customer")
 */
class Author extends \XLite\View\AView
{
    /**
     * Return list of targets allowed for this widget
     *
     * @return array
     */
    public static function getAllowedTargets()
    {
        $result = parent::getAllowedTargets();
        $result[] = 'author';
      

        return $result;
    }


    public function findAuthor()
    {




    $author_id = $this->getAuthorId();
    $author = \XLite\Core\Database::getRepo('XLite\Module\EdB\Librairie\Model\Au
thor')->find($author_id);
    return $author;
    }

    public function describeAuthor()
    {
    $author = $this->findAuthor();
    $value = $author->getDescription();
    $value = \XLite\Model\Base\Catalog::getPreprocessedValue($value);
    echo $value;
    }
    protected function getDefaultTemplate()
    {
          return 'modules/EdB/Librairie/aut1.twig';
    }
}

with the twig file skins/customer/modules/EdB/Librairie/aut1.twig

{{widget('\\XLite\\View\\Image', image=this.findAuthor().getImage(), className='
photo product-thumbnail', verticalAlign='top', id='product_image_' ~ this.findAu
thor().author_id, maxWidth=600, maxHeight=600, alt='') }}
{{this.findAuthor().name}}
<br>
<br>
{{this.describeAuthor()}}

This part is working. Now, to output the list of books by the author, I have another widget Librairie/View/ItemsList/Product/Customer/BooksBy.php with the following
content (below, I removed the part that "should" define which products to show, so
with this we get all products).

<?php 
namespace XLite\Module\EdB\Librairie\View\ItemsList\Product\Customer; 
/** 
 * 
 * @ListChild (list="center.bottom", zone="customer", weight="300") 
 */ 

class BooksBy extends \XLite\View\ItemsList\Product\Customer\ACustomer

{ 
protected $BooksbyAuthor = null;
    protected static function getWidgetTarget()
    {
        return 'author';
    }

    public static function getAllowedTargets()  
    {  
        $result = parent::getAllowedTargets();

        $result[] = self::getWidgetTarget();

        return $result;
    } 

    protected function getData(\XLite\Core\CommonCell $cnd, $countOnly = false)
    {
      return \XLite\Core\Database::getRepo('\XLite\Model\Product')->search(
            $cnd, $countOnly);
    }

    protected function getPagerClass()
    {
        return 'XLite\Module\EdB\Librairie\View\Pager\Customer\Product\Product';
    }
    
}

Of course, I could join the xc_products table with xc_product_author_links table and create a query condition, write a function in Repo class, and this might take less time to finish writing up. However, as I already have pulled the author entity with all properties, including getProducts() which gives an array of products, I would rather use this array to "feed" the getData function.



Now, I encounter two problems.

1. How to pass an array or even a function from viewer widget to the itemlists widget?
2. How to transform an array to the return of the getData function?

For the first point, most of my trials ended up with " Using $this when not in object context" or "call to undefined function", so for now I have reproduced the function in ItemsList file, that is

    public function findBooks()
    {
    $author_id = \XLite\Core\Request::getInstance()->author_id;
    $author = \XLite\Core\Database::getRepo('XLite\Module\EdB\Librairie\Model\Au
thor')->find($author_id);
    $products = $author->getProducts();
    return $products;
    }

This is already in Model class and Viewer class, so I really would like to remove these lines, but for now, it works. As to the second issue, the closest thing
I have seen is
https://forum.x-cart.com/showthread.php?t=70741


so I tried the following (among others)

protected $BooksbyAuthor = null;

    protected function getData(\XLite\Core\CommonCell $cnd, $countOnly = false)
    {
if(!isset($this->BooksbyAuthor)) {
$this->BooksbyAuthor = $this->findBooks();
}
return true == $countOnly
?count($this->BooksbyAuthor)
: $this->BooksbyAuthor;
}

but this leads to

       ERROR: "0" (code N/A)
       Argument 2 passed to  XLite\Core\Model\EntityVersion\BulkEntityVersionFetcher::__construct()  must be of the type array, null given, called in  /srv/http/newbtq72/xcart-53/var/run/classes/XLite/View/ItemsList/Product/Customer/ACustomerAbstract.php  on line 918

and in the log, I find,

XLite [warning] Warning: array_map(): Argument #2 should be an array in /srv/http/newbtq72/xcart-53/var/run/classes/XLite/View/ItemsList/Product/Customer/ACustomerAbstract.php on line 916
     

So, would anyone have any advice on this?