Codeception, write acceptance tests with the pageObject design pattern and gherkin

I'm looking for a simple example of code with the pageObject design pattern and gherkin because when I follow the codeception BDD documentation, all examples written in the tests/support/AcceptanceTester.php. I don't understand (poor english skills --) how not concentrate all code in the AcceptanceTester.php file.

By example, I have a sample home page with two buttons A and B. If the user click on the button A, the page A is loaded else if the user click on button B, the page B is loaded.

Currently, my AcceptanceTester :

<?php
// tests/_support/AcceptanceTester.php
/**
 * Inherited Methods
 * @method void wantToTest($text)
 * @method void wantTo($text)
 * @method void execute($callable)
 * @method void expectTo($prediction)
 * @method void expect($prediction)
 * @method void amGoingTo($argumentation)
 * @method void am($role)
 * @method void lookForwardTo($achieveValue)
 * @method void comment($description)
 * @method \Codeception\Lib\Friend haveFriend($name, $actorClass = NULL)
 *
 * @SuppressWarnings(PHPMD)
 */

class AcceptanceTester extends \Codeception\Actor
{
    use _generated\AcceptanceTesterActions;

    /**
     * @Given The home page
     */
    public function inHomePage()
    {
        $this->amOnPage("/");
        $this->seeInTitle('home');
    }

    /**
     * @When I click on the button A
     */
    public function goToThePageA()
    {
        $this->click(['name' => 'A']);
    }

    /**
     * @Then l go to the page A
     */
    public function ImInPageA()
    {
        $this->seeInTitle('page A');
    }

    /**
     * @When I click on the button B
     */
    public function goToThePageB()
    {
        $this->click(['name' => 'B']);
    }

    /**
     * @Then l go to the page B
     */
    public function ImInPageB()
    {
        $this->seeInTitle('page B');
    }
}

If I run the command './vendor/bin/codecept run acceptance', all works like a charm. But as I said previously, I want learn how don't concentrate all code in the AcceptanceTester file.

So, I created three pageObjects ; one for the home page, one for the page A and one for the page B. The code :

the home pageObject :

<?php
// tests/_support/Page/PageHome.php
namespace Page;

class PageHome
{
    public static $URL = '/home';
    public static $title = "home";
    public static $aButton = ['name' => 'A'] ;
    public static $bButton = ['name' => 'B'] ;

    public static function route($param){
        return static::$URL.$param;
    }

    /**
     * @var \AcceptanceTester;
     */
    protected $acceptanceTester;

    public function __construct(\AcceptanceTester $I){
        $this->acceptanceTester = $I;
    }
}

the A pageObject :

<?php
// tests/_support/Page/PageA.php
namespace Page;

class PageA
{
    public static $URL = '/home/pageA';
    public static $title = "page A";

    public static function route($param){
        return static::$URL.$param;
    }

    /**
     * @var \AcceptanceTester;
     */
    protected $acceptanceTester;

    public function __construct(\AcceptanceTester $I){
        $this->acceptanceTester = $I;
    }
}

And the B pageObject :

<?php
// tests/_support/Page/PageB.php
namespace Page;

class PageB
{
    public static $URL = '/home/pageB';
    public static $title = "page B";

    public static function route($param){
        return static::$URL.$param;
    }

    /**
     * @var \AcceptanceTester;
     */
    protected $acceptanceTester;

    public function __construct(\AcceptanceTester $I){
        $this->acceptanceTester = $I;
    }
}

Then, I created three stepObjects ; homeChecker, goToPageA, goToPageB

The homeChecker stepObject :

<?php
// tests/_support/Step/Acceptance/HomeChecker.php

namespace Step\Acceptance;
use Page\Acceotance\HomePage;

class HomeChecker extends \AcceptanceTester
{
    /**
     * @Given The home page
     */
    public function main()
    {
        $homePage = new PageHome($this);

        $this->amOnPage($homePage::URL);
        $this->checkTitle($homePage);
        $this->checkButtons($homePage);
    }

    private function checkTitle($homePage){
        $this->seeInTitle($homePage::$title);
    }

    private function checkButtons($homePage){
        $this->see($homePage::$aButton);
        $this->see($homePage::$bButton);
    }
}

The PageAChecker stepObject :

<?php
// tests/_support/Step/Acceptance/PageAChecker.php

namespace Step\Acceptance;
use Page\Acceotance\PageHome;
use Page\Acceotance\PageA;

class PageAChecker extends \AcceptanceTester
{
    /**
     * @When I click on the button A
     */
    public function clickButton()
    {
        $homePage = new PageHome($this);
        $this->click($homePage::$aButton);
    }

    /**
     * @Then l go to the page A
     */
    public function checkTitle()
    {
        $aPage = new PageA($this);
        $this->seeInTitle($aPage::$title);
    }

}

And the PageBChecker stepObject :

<?php
// tests/_support/Step/Acceptance/PageBChecker.php

namespace Step\Acceptance;
use Page\Acceotance\PageHome;
use Page\Acceotance\PageB;

class PageBChecker extends \AcceptanceTester
{
    /**
     * @When I click on the button B
     */
    public function clickButton()
    {
        $homePage = new PageHome($this);
        $this->click($homePage::$bButton);
    }

    /**
     * @Then l go to the page B
     */
    public function checkTitle()
    {
        $bPage = new PageB($this);
        $this->seeInTitle($bPage::$title);
    }

}

And now, I don't know what I must do. If I empty my AcceptanceTester file and run again the './vendor/bin/codecept run acceptance' command, the test is incomplete and I get "not found in contexts" warnings in my shell :

What do I do ?

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