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

Question

I'm working through Practical Web 2.0 Appications currently and have hit a bit of a roadblock. I'm trying to get PHP, MySQL, Apache, Smarty and the Zend Framework all working correctly so I can begin to build the application. I have gotten the bootstrap file for Zend working, shown here:
<?php
require_once('Zend/Loader.php');
Zend_Loader::registerAutoload();
// load the application configuration
$config = new Zend_Config_Ini('../settings.ini', 'development');
Zend_Registry::set('config', $config);
// create the application logger
$logger = new Zend_Log(new Zend_Log_Writer_Stream($config->logging->file));
Zend_Registry::set('logger', $logger);
// connect to the database
$params = array('host' => $config->database->hostname,
'username' => $config->database->username,
'password' => $config->database->password,
'dbname' => $config->database->database);
$db = Zend_Db::factory($config->database->type, $params);
Zend_Registry::set('db', $db);
// handle the user request
$controller = Zend_Controller_Front::getInstance();
$controller->setControllerDirectory($config->paths->base .
'/include/Controllers');
// setup the view renderer
$vr = new Zend_Controller_Action_Helper_ViewRenderer();
$vr->setView(new Templater());
$vr->setViewSuffix('tpl');
Zend_Controller_Action_HelperBroker::addHelper($vr);
$controller->dispatch();
?>
This calls the IndexController. The error comes with the use of this Templater.php to implement Smarty with Zend:
<?php
class Templater extends Zend_View_Abstract
{
protected $_path;
protected $_engine;
public function __construct()
{
$config = Zend_Registry::get('config');
require_once('Smarty/Smarty.class.php');
$this->_engine = new Smarty();
$this->_engine->template_dir = $config->paths->templates;
$this->_engine->compile_dir = sprintf('%s/tmp/templates_c',
$config->paths->data);
$this->_engine->plugins_dir = array($config->paths->base .
'/include/Templater/plugins',
'plugins');
}
public function getEngine()
{
return $this->_engine;
}
public function __set($key, $val)
{
$this->_engine->assign($key, $val);
}
public function __get($key)
{
return $this->_engine->get_template_vars($key);
}
public function __isset($key)
{
return $this->_engine->get_template_vars($key) !== null;
}
public function __unset($key)
{
$this->_engine->clear_assign($key);
}
public function assign($spec, $value = null)
{
if (is_array($spec)) {
$this->_engine->assign($spec);
return;
}
$this->_engine->assign($spec, $value);
}
public function clearVars()
{
$this->_engine->clear_all_assign();
}
public function render($name)
{
return $this->_engine->fetch(strtolower($name));
}
public function _run()
{ }
}
?>
The error I am getting when I load the page is this:
Fatal error: Call to a member function fetch() on a non-object in /var/www/phpweb20/include/Templater.php on line 60
I understand it doesn't see $name as an object, but I don't know how to go about fixing this. Isn't the controller supposed to refer to the index.tpl? I haven't been able to discover what the $name variable represents and how to fix this to get the foundation working.
Any help you have is much appreciated!

Answer 1

The problem isn't with the $name variable but rather with the $_engine variable. It's currently empty. You need to verify that the path specification to Smarty.class.php is correct.
You might try this to begin your debugging:
$this->_engine = new Smarty();
print_r($this->_engine);
If it turns out that $_engine is correct at that stage then verify that it is still correctly populated within the render() function.

Answer 2

Zend has an example of creating a templating system which implements the Zend_View_Interface here: http://framework.zend.com/manual/en/zend.view.scripts.html#zend.view.scripts.templates.interface
That might save you some time from trying to debug a custom solution.

Answer 3

removing the __construct method, from the class, solved the similar issue I was facing.

Answer 4

Renaming __construct() to Tempater() worked for me.