Extenders - How to populate custom placeholders?

45 Posts

ram Reply #1, 18 years, 4 months ago

Split off from my previous question about @EVAL & PHx as the question is slightly different now.

Looking for some insight on the process of populating custom placeholders created with Ditto extenders.

I’ve got the following code currently:

Ditto call:

[!Ditto? &parents=`21,23,26` &total=`3` &tpl=`tcTplShopItem` &tplLast=`tcTplShopItemLast` &extenders=`tcPriceGetter`!]

tcPriceGetter.extender.inc.php:

<?php

if (!function_exists("tcPriceGetter")) {
	function tcPriceGetter($resource) {
		$productID = $resource["tcProductID"];
		$query = "SELECT amount FROM modx_treasure_chest WHERE id=$productID";
		$tcPrice = $modx->db->query($query);
		return $tcPrice;
	}
}

$placeholders['tcPrice'] = array("tcPriceGetter","tcProductID");

?>

This pulls the value of [*tcProductID*] (same as row ID) and uses this to pull the relevant price value from the table modx_treasure_chest.

However on trying this it errors with:

Error:	call_user_func(tcProductID) [function.call-user-func]: First argument is expected to be a valid callback	 
Line 259 source:	 $placeholders[$name] = call_user_func($value[1],$resource);

Where am I going wrong?

3,250 Posts

MARKSVIRTUALDESK Reply #2, 18 years, 4 months ago

You have the source and callback swapped. Use this instead:

$placeholders['tcPrice'] = array(array("tcProductID","*"),"tcPriceGetter");

45 Posts

ram Reply #3, 18 years, 4 months ago

It doesn’t seem to like that!

I just get a blank screen returned when I add that to the extender.

There’s no error output in the system event log either.

Ditto call:

[!Ditto? &parents=`21,23,26` &total=`3` &tpl=`tcTplShopItem` &tplLast=`tcTplShopItemLast` &extenders=`tcPriceGetter`!]

Template:

<li>
	<a class="imgPreviewLink" href="[~[+id+]~]" title="[+longtitle+]">
		<img src="/assets/snippets/treasure_chest/images/phpthumb/phpThumb.php?src=../products/[+alias+].jpg&w=125&f=png" alt="[+pagetitle+]">
	</a>
	<h3>
		<a href="[~[+id+]~]" title="[+longtitle+]">[+pagetitle+]</a>
	</h3>
	<p class="productAdd"><a href="#" onclick="return false;" class="addToCart" title="Add this piece to your cart" name="[+tcProductID+]" rel="id"><span>Add To Cart</span></a></p>
	<p>[+tcPrice+]</p>
</li>

tcPriceGetter.extender.inc.php

<?php
if (!function_exists("tcPriceGetter")) {
	function tcPriceGetter($resource) {
		$productID = $resource["tcProductID"];
		$query = "SELECT amount FROM modx_treasure_chest WHERE id=$productID";
		$tcPrice = $modx->db->query($query);
		return $tcPrice;
	}
}

$placeholders['tcPrice'] = array(array("tcProductID","*"),"tcPriceGetter");
?>

3,250 Posts

MARKSVIRTUALDESK Reply #4, 18 years, 4 months ago

Usually a completely blank screen output from MODx is indicative of a error in your PHP syntax. Check to make sure that you have PHP set to display errors so you can locate the typo.

45 Posts

ram Reply #5, 18 years, 4 months ago

Here’s what I got in server error Iog:

[error] PHP Fatal error:  Call to a member function query() on a non-object in /path/assets/snippets/ditto/extenders/tcPriceGetter.extender.inc.php on line 9

Line 9 is the closing bracket of the tcPriceGetter function.

I’m quite lost here!

45 Posts

ram Reply #6, 18 years, 4 months ago

Here we go -

Have got it! Works wonderfully! Thanks for the help.

<?php

if (!function_exists("tcPriceGetter")) {
	function tcPriceGetter($resource) {
		global $modx;
		$productID = $resource["tcProductID"];
		$table = $modx->getFullTableName('treasure_chest');
		
		$query = "SELECT amount FROM $table WHERE id=$productID";
		$result = $modx->db->query($query);
		$tcPrice = $modx->db->getValue($result);
		
		return ($tcPrice < 1) ? 'No price found' : $tcPrice;
	}
}

$placeholders['tcPrice'] = array(array("tcProductID","*"),"tcPriceGetter");

?>

Used $modx->db->getValue to get the value (only want one), all other ways were returning an array, and I wasn’t catering for that at all before. Also did not register $modx as global. Really should make more time for PHP learning!