From php multidimensional array trying to create nested ul li menu (unlimited nested levels)

Question

Here is what i have got http://codepad.org/iDoXXsLX

Have array like this

Array
(
[0] => Array
    (
        [NumberRenamed] => 17
        [TopicName] => Products
        [UpperLevelNumberRenamed] => 0
    )

[17] => Array
    (
        [0] => Array
            (
                [1] => Array
                    (
                        [NumberRenamed] => 18
                        [TopicName] => Computers
                        [UpperLevelNumberRenamed] => 17
                    )
            )
    )

[18] => Array
    (
        [0] => Array
            (
                [2] => Array
                    (
                        [NumberRenamed] => 16
                        [TopicName] => Laptops
                        [UpperLevelNumberRenamed] => 18
                    )
            )
    )

[16] => Array
    (
        [0] => Array
            (
                [4] => Array
                    (
                        [NumberRenamed] => 8
                        [TopicName] => Dell
                        [UpperLevelNumberRenamed] => 16
                    )
            )
    )
)

Top level item is Products, first sub-level item is Computers, next sub-level is Laptops, then again next sub-level Dell

For each sub-level item UpperLevelNumberRenamed == to closest upper level NumberRenamed.

Want to get result like this

Products
  Computers
    Laptops
      Dell
      Acer
    Desktops
Home

Tried this

foreach( $main_topics as $k_main_topics => $v_main_topics ){

if( isset($v_main_topics['UpperLevelNumberRenamed']) and $v_main_topics['UpperLevelNumberRenamed'] == 0 ){
//print only top level topics
echo $v_main_topics['TopicName']. '<br/>';
}

else{//if not top level topic

foreach( $v_main_topics[0] as $k_v_main_topics_0 => $v_v_main_topics_0 ){
echo $v_v_main_topics_0['TopicName']. '<br/>';
}//foreach( $v_main_topics[0] as $k_v_main_topics_0 => $v_v_main_topics_0 )

}//else{

}//foreach( $main_topics as $k_main_topics => $v_main_topics )

But get this

Products
Home
Computers
Laptops
Desktops
Dell
Acer

Something incorrect, but can not understand what. Please, advice what need to correct/change in the code

Trying another way

Initial array is one dimensional array. Trying to get ul li navigation from one dimensional.

Here is what i did http://codepad.org/OLtxyL4X

Answer 1

Here's a summary of what it does:

• flatten the array recursively
• build a multi-dimensional relation map
• create 1D relationships that link UpperLevelNumberRenamed to NumberRenamed
• print out the multi-dimensional as an ul-li list.

Here it is:

$flat = array();
foreach (new RecursiveIteratorIterator(new RecursiveArrayIterator($main_topics)) as $i)
  $flat[] = $i;
$final = array();
$defs = array();
for ($i = 0; $i < count($flat); $i += 3)
    if ($flat[$i + 2] == 0) {
        $final[$flat[$i + 1]] = array();
        $defs[$flat[$i]] = &$final[$flat[$i + 1]];
    } else {
        $defs[$flat[$i + 2]][$flat[$i + 1]] = array();
        $defs[$flat[$i]] = &$defs[$flat[$i + 2]][$flat[$i + 1]];
    }

function array2ul($array) {
    $out = "<ul>";
    foreach($array as $key => $elem)
        $out = is_array($elem) ?
        $out . "<li><span>$key</span>" . array2ul($elem) . "</li>" : 
        $out = $out."<li><span>$key:[$elem]</span></li>";
    $out = $out . "</ul>";
    return $out; 
}

echo array2ul($final);

Output:

<ul><li><span>Products</span><ul><li><span>Computers</span><ul><li><span>Laptops</span><ul><li><span>Dell</span><ul></ul></li><li><span>Acer</span><ul></ul></li></ul></li><li><span>Desktops</span><ul></ul></li></ul></li></ul></li><li><span>Home</span><ul></ul></li></ul>