Magento2 Why I can't get POST data from .\Magento\Framework\App\RequestInterface $request?

Question

This is my code in my module observer

namespace Customtest\Customlogin\Observer;
use \Magento\Framework\Event\Observer;
use \Magento\Framework\Event\ObserverInterface;
class CustomerLogin implements ObserverInterface
{
 protected $_request;
 public function __construct(
 \Magento\Framework\App\RequestInterface $request
 ) {
 $this->_request = $request;
 }
 public function execute(Observer $observer) {
 $post = $this->_request->getPost('login');
 var_dump($post) ;
 }
}

This code is work in localhost but when I upload to live server, Browser

show "http error 500"

Fatal error: Uncaught TypeError: Argument 1 passed to Customtest\Customlogin\Observer\CustomerLogin::__construct() must implement interface Magento\Framework\App\RequestInterface, instance of Magento\Framework\App\ResponseFactory given, called in /opt/stack/magento2/apps/magento/htdocs/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 111 and defined in /opt/stack/magento2/apps/magento/htdocs/app/code/Customtest\Customlogin/Observer/CustomerLogin.php:15 Stack trace: #0 /opt/stack/magento2/apps/magento/htdocs/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php(111): Customtest\Customlogin\Observer\CustomerLogin->__construct(Object(Magento\Framework\App\ResponseFactory), Object(Magento\Framework\Url)) #1 /opt/stack/magento2/apps/magento/htdocs/vendor/magento/framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Customtest\Hello...', Array) #2 /opt/stack/magento2/apps/magento/htdocs/vendor/magento/framework/ObjectManager/Obj in /opt/stack/magento2/apps/magento/htdocs/app/code/Customtest\Customlogin/Observer/CustomerLogin.php on line 15

• Dhaval Solanki: I have updated answer.

Answer 1

I fixed it using

php bin/magento setup:upgrade
php bin/magento setup:di:compile