Notifier/Observer problem editing Real World Example 1

[DrByte]

I was experimenting on this code on WIKI API tutorial. i tried to remove this condition statement " if ($_SESSION['cart']->show_total() < $this->freeAmount && $_SESSION['cart']->in_cart($this->freeProductID) )
{" that is when the error comes up when i'm trying to add a product in the cart. i scanned shopping cart class and still haven't figured why it has to have that statement for the class to work

But ... an "if" clause which contains an opening brace { must also include a closing brace }
And, if you only removed the "if" condition and its opening brace, then you've created an ugly PHP error situation.
If you really want to remove that particular "if" clause, you need to remove the *whole* thing:

  if ($_SESSION['cart']->show_total() < $this->freeAmount && $_SESSION['cart']->in_cart($this->freeProductID) ) 
  {
    $_SESSION['cart']->remove($this->freeProductID);
  }

I recommend going back to the PHP website and studying the code syntax before adjusting further PHP code.

[dale88]

Yes i know it will cause php errors if you don't remove the closing bracket. i removed the condition including the closing bracket.

so the script looks like this

<?php
/**
 * Observer class used to add a free product to the cart if the user spends more than $x
 *
 */
class freeProduct extends base {
  /**
   * The threshold amount the customer needs to spend.
   * 
   * Note this is defined in the shops base currency, and so works with multi currency shops
   *
   * @var decimal
   */
  var $freeAmount = 100;
  /**
   * The id of the free product.
   * 
   * Note. This must be a true free product. e.g. price = 0 Also make sure that if you don't want the customer
   * to be charged shipping on this, that you have it set correctly.
   *
   * @var integer
   */
  var $freeProductID = 15;
  /**
   * constructor method
   * 
   * Attaches our class to the $_SESSION['cart'] class and watches for 2 notifier events.
   */
  function freeProduct() {
    $_SESSION['cart']->attach($this, array('NOTIFIER_CART_ADD_CART_END', 'NOTIFIER_CART_REMOVE_END'));
  }
  /**
   * Update Method
   * 
   * Called by observed class when any of our notifiable events occur
   *
   * @param object $class
   * @param string $eventID
   */
  function update(&$class, $eventID, $paramsArray = array()) {

  if ($eventID == 'NOTIFIER_CART_REMOVE_END' && (isset($_SESSION['freeProductInCart']) && $_SESSION['freeProductInCart'] == TRUE ))
  {
    if (!$_SESSION['cart']->in_cart($this->freeProductID))
    {
      $_SESSION['userRemovedFreeProduct'] = TRUE;
    }
  }

  if (!isset($_SESSION['userRemovedFreeProduct']) || $_SESSION['userRemovedFreeProduct'] != TRUE) 
  {

      $_SESSION['cart']->add_cart($this->freeProductID);
      $_SESSION['freeProductInCart'] = TRUE;  
    }
  
 
  if ($_SESSION['cart']->show_total() < $this->freeAmount && $_SESSION['cart']->in_cart($this->freeProductID) ) 
  {
    $_SESSION['cart']->remove($this->freeProductID);
  }

  if ($_SESSION['cart']->in_cart($this->freeProductID)) 
  {
    $_SESSION['cart']->contents[$this->freeProductID]['qty'] = 1;
  }
   
  }  
}
?>

[DrByte]

Maybe because you're removing some critical logic which protects against re-adding the item to the cart if it's already there? perhaps thus causing an endless loop?

I'm not sure why you would choose to remove that part of the logic in the first place.

[dale88]

I got you. i wanna know the details why is that statement important on the logic. I'm just experimenting the code for learning reasons. Can't seem to find out why is that statement caused errors when removed. all its do is check if amount is more than the free amount. for me, when that statement is removed it should automatically adds the free product on the cart regardless of the amount in the cart. that's what i think the program flow is.

[dale88]

i looked at the add cart function on shopping cart class. there is an $this->in_cart statement there, so the product is also checked in there. and also i tried removing just the "$_SESSION['cart']->show_total() >= $this->freeAmount" and did not remove "!$_SESSION['cart']->in_cart($this->freeProductID" same error occurs. so the in_cart statement is not the issue here

[DrByte]

Feel free to enlighten us when you figure out why.

[dale88]

Sure but i was hoping if anyone could help me

[dale88]

After scanning through the code. i guess the problem is a looping error. if statement is remove it will cause an infinite loop