Working with Global Variables

[SchweppesAle]

hi, I'm not really sure why the following code is returning a "Call to a member function getBanners() on a non-object" error message.

 

  
   var $_model;
   
   function display ($tpl=null)
   {
          $this->_model = &$this->getModel();
  global $option,$mainframe, $_model;
          
  $Banners = $_model->getBanners();


  $this->assignRef('Banners', $Banners);
          parent::dislay($tpl);
   }

 

if I replace "$Banners = $_model->getBanners();" with  "$Banners = $this->_model->getBanners();" it works fine, I'm trying to shorten the code though.

[trq]

You haven't defined $_model() anywhere, only $this->_model().

[oni-kun]

Hmm..

 

"parent::dislay($tpl);"

 

You forgot the 'p'!

[SchweppesAle]

This is the entire class.  I thought I was already declaring the value of $_model with "$this->_model = &$this->getModel();"

 

<?php
defined('_JEXEC') or die ('restricted access');

jimport('joomla.application.component.view');

class JtbannersViewList extends JView
{
    
   var $_model;
   
   function display ($tpl=null)
   {
          $this->_model = &$this->getModel();
  global $option,$mainframe, $_model;
          
  $Banners = $_model->getBanners();


  $this->assignRef('Banners', $Banners);
          parent::dislay($tpl);
   }
   
}


?>

 

 

[oni-kun]

     $this->assignRef('Banners', $Banners);
          parent::dislay($tpl);
   }

 

Why are you ignoring such an obvious mistake?

[trq]

I thought I was already declaring the value of $_model with "$this->_model = &$this->getModel();"

 

Yes, but any variable declared outside of a method must be pre-pended with $this-> within a method to access it.

 

Also, using the global keyword within a class (or most anytime really) breaks your encapsulation. You may as well not bother using classes or functions at all.

[SchweppesAle]

I thought I was already declaring the value of $_model with "$this->_model = &$this->getModel();"

 

Yes, but any variable declared outside of a method must be pre-pended with $this-> within a method to access it.

 

Also, using the global keyword within a class (or most anytime really) breaks your encapsulation. You may as well not bother using classes or functions at all.

 

Good point.I just realized the manual wasn't referring to classes.

http://php.net/manual/en/language.variables.scope.php

 

This works though, probably much simpler too

 

defined('_JEXEC') or die ('restricted access');

jimport('joomla.application.component.view');

class JtbannersViewList extends JView
{
    
   
   function display($tpl=null)
   {
          $model = &$this->getModel();
  $Banners = $model->getBanners();


 $this->assignRef('Banners', $Banners);
         parent::display($tpl); 
   }
   
}