Recursive function - tree view - <ul> <li> ... (stuck) - php

Question

It seems that I'm stuck with my recursive function.
I have a problem with closing the unnamed list (</ul>) and the list-items (</li>)
The thing what i get is
-aaa
-bbb
-b11
-b22
-b33
-ccc
-c11
-c22
-c33
-ddd
-d11
-d22
-d33
-eee
-fff
And the thing what i want is:
-aaa
-bbb
-b11
-b22
-b2a
-b2c
-b2b
-b33
-ccc
-c11
-c22
-c33
-c2a
-c2c
-c2c1
-c2c2
-c2b
-ddd
-d11
-d22
-d33
-eee
-fff
This is the code that i'm using
$html .= '<ul>';
$i = 0;
foreach ($result as $item)
{
$html .= "<li>$item->id";
$html .= getSubjects($item->id, NULL, "",$i); <--- start
$html .= "</li>";
}
$html .= '</ul>';
And the function
function getSubjects($chapter_id = NULL, $subject_id = NULL, $string = '', $i = 0 ) {
$i++;
// getting the information out of the database
// Depending of his parent was a chapter or a subject
$query = db_select('course_subject', 'su');
//JOIN node with users
$query->join('course_general_info', 'g', 'su.general_info_id = g.id');
// If his parent was a chapter - get all the values where chapter id = ...
if ($chapter_id != NULL) {
$query
->fields('g', array('short_title', 'general_id'))
->fields('su', array('id'))
->condition('su.chapter_id', $chapter_id, '=');
$result = $query->execute();
}
// if the parent is a subject -
// get value all the values where subject id = ...
else {
$query
->fields('g', array('short_title', 'general_id'))
->fields('su', array('id'))
->condition('su.subject_id', $subject_id, '=');
$result = $query->execute();
}
// Because count doesn't work (drupal)
$int = 0;
foreach ($result as $t) {
$int++;
}
// if there no values in result - than return the string
if ($int == 0) {
return $string;
}
else {
// Creating a new <ul>
$string .= "<ul>";
foreach ($result as $item) {
// change the id's
$subject_id = $item->id;
$chapter_id = NULL;
// and set the string --> with the function to his own function
$string .= "<li>$item->short_title - id - $item->id ";
getSubjects(NULL, $subject_id, $string, $i);
$string .="</li>";
}
$string .= "</ul>";
}
// I thougt that this return wasn't necessary
return $string;
}
Does someone have more experience with this kind of things?
All help is welcome.

Answer 1

I am not sure what you are trying to do but here is some code you can test and see if it helps to solve your problem:
This part is just for testing, it makes three dimensional array for testing:
for ($x = 0; $x < 2; $x++) {
$result["c$x"] = "ROOT-{$x}";
for ($y = 0; $y < 3; $y++) {
$result[$x]["c$y"] = "SECOND-{$x}-{$y}";
$rnd_count1 = rand(0,3);
for ($z = 0; $z < $rnd_count1; $z++) {
$result[$x][$y]["c$z"] = "RND-{$x}-{$y}-{$z}";
$rnd_count2 = rand(0,4);
for ($c = 0; $c < $rnd_count2; $c++) {
$result[$x][$y][$z][$c] = "LAST-{$x}-{$y}-{$z}-{$c}";
}
}
}
}
// $result is now four dimensional array with some values
// Last two levels gets random count starting from 0 items.
UPDATE:
Added some randomness and fourth level to test array.
And here is function which sorts array to unordered list:
function recursive(array $array, $list_open = false){
foreach ($array as $item) {
if (is_array($item)) {
$html .= "<ul>\n";
$html .= recursive($item, true);
$html .= "</ul>\n";
$list_open = false;
} else {
if (!$list_open) {
$html .= "<ul>\n";
$list_open = true;
}
$html .= "\t<li>$item</li>\n";
}
}
if ($list_open) $html .= "</ul>\n";
return $html;
}
// Then test run, output results to page:
echo recursive($result);
UPDATE:
Now it should open and close <ul> tags properly.