Hello World Module Error

Question

I am following Alan Storm's tutorial and am getting an error

Controller:

<?php
namespace Pulsestorm\HelloWorldMVVM\Controller\Hello;
use Magento\Framework\View\Result\PageFactory;
use Magento\Framework\App\Action\Context;
class World extends \Magento\Framework\App\Action\Action
{
    protected $pageFactory;
    public function __construct(Context $context, PageFactory $pageFactory)
    {
        $this->pageFactory = $pageFactory;
        return parent::__construct($context);
    }

    public function execute()
    {
        var_dump(__METHOD__);
        $page_object = $this->pageFactory->create();;
        return $page_object;
    }
}

Error:

Fatal error: Uncaught ArgumentCountError: Too few arguments to function Pulsestorm\HelloWorldMVVM\Controller\Hello\World::__construct(), 1 passed in /var/www/html/generated/code/Pulsestorm/HelloWorldMVVM/Controller/Hello/World/Interceptor.php on line 14 and exactly 2 expected in /var/www/html/app/code/Pulsestorm/HelloWorldMVVM/Controller/Hello/World.php:9 Stack trace: #0 /var/www/html/generated/code/Pulsestorm/HelloWorldMVVM/Controller/Hello/World/Interceptor.php(14): Pulsestorm\HelloWorldMVVM\Controller\Hello\World->__construct(Object(Magento\Framework\App\Action\Context)) #1 /var/www/html/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php(111): Pulsestorm\HelloWorldMVVM\Controller\Hello\World\Interceptor->__construct(Object(Magento\Framework\App\Action\Context)) #2 /var/www/html/vendor/magento/framework/ObjectManager/Factory/Dynamic/Developer.php(66): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Pulsestorm\\Hell...', Array) #3 /var/www/html/vendor/magento/framework/ObjectManager in /var/www/html/app/code/Pulsestorm/HelloWorldMVVM/Controller/Hello/World.php on line 9

Answer 1

The full code your Controller file is something like below:

<?php

namespace Pulsestorm\HelloWorldMVVM\Controller\Hello;

use Magento\Framework\View\Result\PageFactory;

class World extends \Magento\Framework\App\Action\Action
{
    /**
     * @var PageFactory
     */
    protected $pageFactory;

    /**
     * @param \Magento\Framework\App\Action\Context $context
     * @param PageFactory $pageFactory
     */
    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        PageFactory $pageFactory
    ) {
        $this->pageFactory = $pageFactory;
        parent::__construct($context);
    }

    public function execute()
    {
        echo "Hello World"; exit;
    }
}

Note: in that tutorial $page_object = $this->pageFactory->create(); this line is having 2 semi colon. remove 1 from it. Run below commands in sequence.

php bin/magento cache:flush
php bin/magento cache:clean
php bin/magento setup:upgrade
bin/magento setup:di:compile
From magento root directory: chmod -R 777 var/*

Answer 2

Just kill magento_root/var/generation and magento_root/var/di or magento_root/generated if you use 2.2 version and clear cache. Don't forget to leave .htaccess files in that folders.