Call to a member function on null - php

Question

I create service for add formType then persist object and in controller I invoke data but I have error shown on below image:
in controller i extend class abstractController content getHandler and I have view newskill.html.twig
Code SkillController.php:
<?php
namespace AppBundle\Controller\Condidate;
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route;
use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Request;
use AppBundle\Entity\Skill;
use AppBundle\Controller\AbstractController;
use AppBundle\Form\SkillType;
/**
*Class SkillController.
*/
class SkillController extends AbstractController
{
/**
*function handler.
*/
protected function getHandler(){
//var_dump('test');
}
/**
*function addSkill
* #param Request $request
* #return \Symfony\Component\Form\Form The form
*/
public function addSkillAction(Request $request) {
$skill = $this->getHandler()->post();
if ($skill instanceof \AppBundle\Entity\Skill) {
return $this->redirectToRoute('ajouter_info');
}
return $this->render('skills/newskill.html.twig', array(
'form' => $form->createView(),));
}
}
Code SkillHandler.php:
<?php
namespace AppBundle\Handler;
use AppBundle\Handler\HandlerInterface;
use Symfony\Component\HttpFoundation\Request;
use AppBundle\Entity\Skill;
use Doctrine\ORM\EntityManager;
use Symfony\Component\DependencyInjection\Container;
use Symfony\Component\Form\formFactory;
/**
* SkillHandler.
*/
class SkillHandler implements HandlerInterface {
/**
*
* #var EntityManager
*/
protected $em;
/**
*
* #var formFactory
*/
private $formFactory;
/**
*function construct.
*/
public function __construct(EntityManager $entityManager, formFactory $formFactory)
{
$this->em = $entityManager;
$this->formFactory = $formFactory;
}
/**
*function post
*/
public function post(array $parameters, array $options = []) {
$form = $this->formFactory->create(\AppBundle\Form\SkillType::class, $object, $options);
$form->submit($parameters);
if ($form->isValid()) {
$skill = $form->getData();
$this->persistAndFlush($skill);
return $skill;
}
return $form->getData();
}
/**
*function persisteAndFlush
*/
protected function persistAndFlush($object) {
$this->em->persist($object);
$this->em->flush();
}
/**
*function get
*/
public function get($id){
throw new \DomainException('Method SkillHandler::get not implemented');
}
/**
*function all
*/
public function all($limit = 10, $offset = 0){
throw new \DomainException('Method SkillHandler::all not implemented');
}
/**
*function put
*/
public function put($resource, array $parameters, array $options){
throw new \DomainException('Method SkillHandler::put not implemented');
}
/**
*function patch
*/
public function patch($resource, array $parameters, array $options){
throw new \DomainException('Method SkillHandler::patch not implemented');
}
/**
*function delete
*/
public function delete($resource){
throw new \DomainException('Method SkillHandler::delete not implemented');
}
}
code services.yml:
skill_add:
class: AppBundle\Handler\SkillHandler
arguments:
- "#doctrine.orm.entity_manager"
- "#form.factory"
public: true
Any help would be appreciated.

Answer 1

Your $this->getHandler() retruns null.
Solution can be checking if $this->getHandler() doesn't return null in first place.
if (!$this->getHandler()) {
throw new \Exception(sprintf('Handler cannot be null')
} else {
$skill = $this->getHandler()->post();
}

Answer 2

Try this, firstly you should take your handler into getHandler() method at your Controller.
protected function getHandler(){
return $this->get('skill_add');
}