ZF2 - Call to a member function on a non-object error - php

Question

I am trying to implement a simple roll-a-dice service and use it in a .phtml file. I know my issue has been reported often on SO, but I could not find a solution in other questions.
I get the following error message:
Fatal error: Call to a member function getDiceResult()
on a non-object in rolladice.phtml on line 11
Here is line 11:
<?php
$result = $this->rollADiceService->getDiceResult();
echo "<p>Roll-a-dice result: ".$result."</p>";
?>
The controller is set-up as following:
class RollADiceController extends AbstractActionController
{
private $rollADiceService;
public function setPluginManager(PluginManager $plugins) {
parent::setPluginManager($plugins);
$this->rollADiceService = $this->getServiceLocator()
->get('RollADiceService');
}
...
In Module.php, I have:
public function getServiceConfig()
{
return array(
'factories'=>array(
'LoginLogoutService' => function() {
return new LoginLogoutService();
},
'RollADiceService' => function() {
return new RollADiceService();
},
),
);
}
I am using the same technique (i.e., setPluginManager) to retrieve instances of my services in other controllers without issues. What am I doing wrong?
P.S.: Using a debugger, I can see that setPluginManager() is called, but that the $this->rollADiceService variable is initialized with null. Why?

Answer 1

Ultimately, there were two issues:
i) I refactored my code to pass the result of the call to rollADiceService->getDiceResult() as a variable which $this can access.
ii) Hijacking setPluginManager() is not a recommended practice. I've implemented factories for my controllers depending on services.

Answer 2

your problem is realy simple I think.
<?php
$result = $this->rollADiceService()->getDiceResult();
echo "<p>Roll-a-dice result: ".$result."</p>";
?>
Add these brackets after rollADiceService should fix your problem. Without brackets, Zend View instance try to access to view variable named rollADiceService, which is obviously NULL.
By adding brackets, you tell to View it should look for rollADiceService in registered view helpers.
I hope it helps :)