Nested List with RecursiveArrayIterator

[ablock]

Using standard recursion I would do something like this

function print_list($data $depth = 1) {
    echo str_repeat("\t", $depth - 1), "<ul>", PHP_EOL;
    foreach ($array as $key => $val) {
        if (is_array($val)) {
            echo str_repeat("\t", $depth),"<li>", $key, PHP_EOL, print_list($val, $depth + 1), "</li>", PHP_EOL;     
        }
        else {
            echo str_repeat("\t", $depth), "<li>",$val,"</li>", PHP_EOL;
        }
    }
    echo str_repeat("\t", $depth - 1),"</ul>", PHP_EOL;
} 

For an array like

$array = array(
    "Level 1" => array (
        "Level 2" => array(
            "Item 1", "Item 2"
        ),
        "Level 2" => array(
            "Item 1", "Item 2"
        )
    )
); 

And this produces a nice XHTML compliant list

<ul>
        <li>Level 1
        <ul>
                <li>Level 2
                <ul>
                        <li>Item 1</li>
                        <li>Item 2</li>
                </ul>
				</li>
                <li>Level 2
                <ul>
                        <li>Item 1</li>
                        <li>Item 2</li>
                </ul>
				</li>
        </ul>
		</li>
</ul>

I would like to do this with the SPL's RecursiveIteratorIterator...
My failed attempt looks like this:

class RecursiveListIterator extends RecursiveIteratorIterator {
    function beginChildren() {
        echo str_repeat("\t", $this->getDepth() );
        echo "<ul>\n";
        
    }
    
    function endChildren() {
        echo str_repeat("\t", $this->getDepth());
        echo "</ul>\n";
    }
}

$it = new RecursiveListIterator(new RecursiveArrayIterator($array), RecursiveIteratorIterator::SELF_FIRST ); 
foreach($it as $key => $item) {
    echo "<li>";
    if ($it->getInnerIterator()->hasChildren()) {
            echo $key;
    }
    else {
            echo $item;
    }
    echo "</li>";
} 

This creates an "</li>" after every item as opposed to my recursive function which recursively prints the child lists before enclosing the "<li>"

I feel like the solution is there, and I just need to modify one small thing, but I can't find it.

[Salathe]

I've not really done a lot with the recursive iterators, so this may not be the best or ideal approach, but here's something which seems to work as you want it to or at least will provide a little step forward (I hope).

<?php header('Content-Type: text/html; charset=utf-8'); error_reporting(E_ALL | E_STRICT);

$array = array(
    "Level 1" => array (
        "Level 2.1" => array(
            "Item 3.1", "Item 3.2"
        ),
        "Level 2.2" => array(
            "Item 3.3", "Item 3.4"
        ),
        "Level 2.3" // => array()
    )
);

class RecursiveListIterator extends RecursiveIteratorIterator {
    
    public $tab = "\t";
    
    public function beginChildren() {
        if (count($this->getInnerIterator()) == 0) { return; }
        echo str_repeat($this->tab, $this->getDepth()), "<ul>\n";
    }
    
    public function endChildren() {
        if (count($this->getInnerIterator()) == 0) { return; }
        echo str_repeat($this->tab, $this->getDepth()), "</ul>\n";
        echo str_repeat($this->tab, $this->getDepth()), "</li>\n";
    }
    
    public function nextElement() {
        // Display leaf node 
        if ( ! $this->callHasChildren()) {
            echo str_repeat($this->tab, $this->getDepth()+1), '<li>', $this->current(), "</li>\n";
            return;
        }
        
        // Display branch with label
        echo str_repeat($this->tab, $this->getDepth()+1), '<li>', $this->key();
        echo (count($this->callGetChildren()) == 0) ? "</li>\n" : "\n";
    }
}

$it = new RecursiveListIterator(new RecursiveArrayIterator($array), RecursiveIteratorIterator::SELF_FIRST); 
echo "<ul>\n";
foreach($it as $key => $item); 
echo "</ul>\n";