can I add an object to an array?

Toadums

I hope I can do this or I am hooped 😛

So what I have is a stack...here is the push function:

public function push($item) { // Shove an element on the stack
		if (array_push($this->stack, $item)) {
			return TRUE;
		} else {
			return FALSE;
		}
	}

i am pushing something on in this line:

 else if($pointerKey != $parentKey){
	 			$stack->push($pointer);
	 			if($pointer->getNext() != null){
				 	$pointer = $pointer->getNext();
				 }else{
				 	$lastInColumn = true;

			 }
 		}

pointer is of the nodeClass() class which I created...

I get an error here (on the line that says: if($peek->getChild() != null) ):

the error says: "Fatal error: Call to a member function getData() on a non-object in /home/toadums/pdem.info/Standards/testTreeview.php on line 159"

if($lastInColumn == true){
	 			$childCheck = false;
	 			while($childCheck == false){

	 			$peek = $stack->peek();

	 			if($peek->getChild() != null){ //<<ERROR HERE
	 				$pointer = $peek->getChild();
	 				$lastInColumn = false;
	 				$childCheck = true;
			 	}else{
			 		$stack->pop();
			 	}
	 		}
 		}

Any ideas? when it is pushed onto the stack does it turn it from a nodeClass object to something else? do I need to say somewhere that I want to add the object as an object?

Thanks!

Shrike

The error refers to getData but the line you mention refers to getChild. That doesn't sound right. What code do you have in getChild?

Objects can be stored in arrays without issue. I suspect the problem is elsewhere.

Toadums

Shrike;10920607 wrote:
The error refers to getData but the line you mention refers to getChild.

errr..sorry, when I copied the code, i had something like echo $peek->getData();...for testing purposes.

the strange part is..when I had that written down, it ECHOED what $peek->getData() was..and then gave the error after..

Get child is simply:

function getChild()
    {
    	return $this->child;
    }

here is the entire while loop with everything that may effect it (i will add a comment where the stack/peek business starts)

Thanks for looking at this!! hopfully its not too big of a problem >.<

$head = new nodeClass("head",null,null);



while($i < $num){

if(mysql_result($result,$i,"Part")!=null){

	$newNode = new nodeClass("pa".$a,null,mysql_result($result,$i,"Part"));
	$a++;

}elseif(mysql_result($result,$i,"Tier1")!=null){

	$newNode = new nodeClass("t1".$b,"pa".$a,mysql_result($result,$i,"Tier1"));
	$b++;

}elseif(mysql_result($result,$i,"Tier2") !=null){

	$newNode = new nodeClass("t2".$c,"t1".$b,mysql_result($result,$i,"Tier2"));
	$c++;

}elseif(mysql_result($result,$i,"Tier3") !=null){

	$newNode = new nodeClass("t3".$d,"t2".$c,mysql_result($result,$i,"Tier3"));
	$d++;

}elseif(mysql_result($result,$i,"Tier4") !=null){

	$newNode = new nodeClass("t4".$e,"t3".$d,mysql_result($result,$i,"Tier4"));
	$e++;

}

if($head->getNext() == null){
	$head->setNext($newNode);
	echo "1<br />";
}



elseif(($head != null)&&($newNode->getParent()==null)){

	$probe = $head;

	$check1=false;
	while($check1 == false){


		if($probe->getNext() == null){
			$check1 = true;
		}else{
		$probe = $probe->getNext();
		}
	}

	$probe->setNext($newNode);

 /*Everything up to this elseif works fine (i commented just this else if, and it 
worked 100% like it should) and then i fixed a few other problems...now the only 
issue seems to be with my stack...granted there is probably another way to do 
this if I cant figure it out, but This would be easiest...*/

}elseif($newNode->getParent() !=null){

	$parent = $newNode->getParent();
	$parentKey = $newNode->getKey();

	$pointer = $head;


	$parentFound = false;
	$lastInColumn = false;
	$stack = new Stack();


 	while($parentFound != true){
 		$pointerKey = $pointer->getKey();

		 if($pointerKey == $parentKey){//stopping condition
 			$parentFound = true;
 			$lastInColumn = false;

 		}else if($pointerKey != $parentKey){

 			if($pointer->getData() != null){
			 $stack->push($pointer);
			}

			 if($pointer->getNext()->getData() != null){
			 	$pointer = $pointer->getNext();
			 }else{
			 	$lastInColumn = true;

			 }
 		}

 		if($lastInColumn == true){
 			$childCheck = false;
 			while($childCheck == false){

	 			$peek = $stack->peek();

	 			if($peek->getChild() != null){
	 				$pointer = $peek->getChild();
	 				$lastInColumn = false;
	 				$childCheck = true;
			 	}else{
			 		$stack->pop();
			 	}
	 		}
 		}



 	}//end while

}



$i++;
}

Shrike

It's hard to say without seeing what the Stack class does. Maybe you are not handling reaching the end of the stack when you call peek?

Toadums

Shrike;10920613 wrote:
Maybe you are not handling reaching the end of the stack when you call peek?

what does that mean?

stack class prety much just makes an array and has a last in first out order to it. so I can only access/see the last element of the array...

here is the whole class..(i pretty much copied it straight from google, so it may be a bit off, but I looked it over and it seemed right..)

<?php
/*********************************************
*    Stack Class    					     *
*  Coded by Moonbat modified by Paul Demchuk *
*  October 5, 2008                           *
*********************************************/
class Stack {

var $stack;

public function __construct() {
	$this->stack = array();
}

public function is_empty() {
	if (empty($this->stack)) {
		return TRUE;
	} else {
		return FALSE;
	}
}

public function size() {
	return count($this->stack);
}

public function push($item) { // Shove an element on the stack
	if (array_push($this->stack, $item)) {
		return TRUE;
	} else {
		return FALSE;
	}
}

public function pad_to($amount, $item = 0) { // Pad the stack with $item until stack size = $amount
	if ($amount < 0 || $amount < $this->size()) {
		return FALSE;
	} else {
		while ($this->size() != $amount) {
			$this->push($item);
		}
		return TRUE;
	}
}

public function pad_extra($amount, $item = 0) { // Pad the stack with $item for $amount times
	if ($amount < 0) {
		return FALSE;
	} else {
		for ($i=0; $i<$amount; $i++) {
			$this->push($item);
		}
		unset($i);
		return TRUE;
	}
}

public function pop() { // Shoot off last item on the stack
	if (!$this->is_empty()) {
		array_pop($this->stack);
		return TRUE;
	} else {
		return FALSE;
	}
}

public function peek() { // Get certain element on the stack
	$elements = count($this->stack);	
	return  $this->stack[$elements-1];
	unset($elements);
	}


public function __destruct() {
	unset($this->stack);
}

}
?>

Shrike

I mean that your peek method is not bounds checked. Is it possible that the stack is empty when you call peek? Have you set error_reporting to include notices?