relation behavior

[as7ali]

I have a problem in relation behavior in backend controller
I used belew codes but when reload backend page get the error 500 in browser and 15 same error in event log with message

Symfony\Component\ErrorHandler\Error\FatalError: Uncaught BadMethodCallException: Call to undefined method System\Models\Parameter::hasDatabaseTable() in C:\xampp\htdocs\mywinter\vendor\laravel\framework\src\Illuminate\Support\Traits\ForwardsCalls.php:71

folder/models
Category.php
public $table = 'as7_relationtest_category'; // table fields : id,name
public $hasMany = [ 'products' => [Product::class] ];
Product.php
public $table = 'as7_relationtest_product'; '; // table fields : id,name,category_id
public $belongsTo = [ 'category' => [Category::class] ];

folder/models/category
fields.yaml
fields:
name:
label: Name
type: text
tabs:
fields:
products:
type: partial
path: $/as7/relationtest/controllers/category/_products.htm
tab: 'Tab 1'

folder/models/product
columns.yaml
columns:
id:
label: id
type: number
name:
label: name
type: text
fields.yaml
fields:
name:
label: Name
type: text

folder/controllers
Category.php
use Backend\Classes\Controller;
use BackendMenu;
class Category extends Controller
{
public $implement = [ 'Backend\Behaviors\ListController', 'Backend\Behaviors\FormController' ,'\Backend\Behaviors\RelationController' ];

public $listConfig = 'config_list.yaml';
public $formConfig = 'config_form.yaml';
public $relationConfig = 'config_relation.yaml';
public function __construct() { parent::__construct();
BackendMenu::setContext('As7.Relationtest', 'main-menu-item'); }}

folder/controllers/category
config_relation.yaml
products:
label: products
manage:
form: $/as7/relationtest/models/product/fields.yaml
list: $/as7/relationtest/models/product/columns.yaml
view:
list: $/as7/relationtest/models/product/columns.yaml
toolbarButtons:

[WebVPF]

Syntax error in folder/models/Product.php

public $table = 'as7_relationtest_product'; ';   // table fields : id,name,category_id
public $belongsTo = [   'category' => [Category::class]    ];

Twice '; '; in t_product'; '; // table

Corrected:

public $table = 'as7_relationtest_product'; // table fields : id,name,category_id

public $belongsTo = [
    'category' => [Category::class]
];

In folder/controllers/Category.php values in $implement

use Backend\Classes\Controller;
use BackendMenu;

class Category extends Controller
{
    public $implement = [
        \Backend\Behaviors\FormController::class,
        \Backend\Behaviors\ListController::class,
        \Backend\Behaviors\RelationController::class,
    ];

    public $listConfig = 'config_list.yaml';
    public $formConfig = 'config_form.yaml';
    public $relationConfig = 'config_relation.yaml';

    public function __construct()
    {
        parent::__construct();
        BackendMenu::setContext('As7.Relationtest', 'main-menu-item');
    }
}