Simple Category Tree

[yellow1912]

1. Loosely based on the Flyout Category Tree mod, use one single sql to query categories, hence reduce the load on server (especially those with large number of categories)
2. Allow users to specify the parent, child tag instead of having to use ul, li
3. Allow the use of session to further reduce the load on server
4. Can build any branch of the category tree.
5. A number of users wanted to list all products in all sub-categories of a specific category, they can take advantage of this mod as well, since it stores all sub-cats of a specific cat in $tree['cat_id']['sub_cats'] array, however, it currently stores the first sub-level, so you have to write a small function to go thru the tree and gather the deepest cats (assuming you understand what I mean ^^)

I wrote this class for my own use, and have no intention to write a detailed instruction, nor provide a downloadable package, nor provide any support at all. Just think that some of you may need it, so I post the code here:

includes/classes/simple_categories_tree_generator.php

<?php
/**
 * Simple Category Tree
 * @Version: Beta 1
 * @Authour: yellow1912
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 */ 

define ('SCT_REBUILD_TREE','false');
class simple_categories_generator{
    var $category_tree = array();

    function simple_categories_generator() {
        if(SCT_REBUILD_TREE != 'false' || count($this->category_tree) == 0){
            global $languages_id, $db;
            $categories_query = "select c.categories_id, cd.categories_name, c.parent_id
                          from " . TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd
                          where c.categories_id = cd.categories_id
                          and c.categories_status=1
                          and cd.language_id = '" . (int)$_SESSION['languages_id'] . "'
                          order by c.parent_id, c.sort_order, cd.categories_name";
            $categories = $db->Execute($categories_query);
    
            while (!$categories->EOF) {
                $this->category_tree[$categories->fields['categories_id']] = array('name' => $categories->fields['categories_name'],
                'parent_id' => $categories->fields['parent_id']);
                $this->category_tree[$categories->fields['categories_id']]['path'][] = $categories->fields['categories_id'];
                $this->category_tree[$categories->fields['parent_id']]['sub_cats'][] = $categories->fields['categories_id'];
                if($categories->fields['parent_id'] > 0){
                    $this->category_tree[$categories->fields['categories_id']]['path'] = array_merge($this->category_tree[$categories->fields['parent_id']]['path'],$this->category_tree[$categories->fields['categories_id']]['path']);
                }
                $this->category_tree[$categories->fields['categories_id']]['cPath'] = implode('_',$this->category_tree[$categories->fields['categories_id']]['path']);        
                $categories->MoveNext();
            }
            // add sub 'class' for print-out purpose
            foreach($this->category_tree as $key => $value){
                $this->category_tree[$key]['sub'] = isset($this->category_tree[$key]['sub_cats']) ? 'has_sub' : 'no_sub';            
            }    
        }
    }

    function build_category_string($parent_tag = 'div', $child_tag = 'span', $categories_id = 0, $include_root = false){
        if(!is_int($categories_id)){
            $temp = explode('_',$categories_id);
            $categories_id = $temp(count($temp)-1);
        }
        $result = '';
        $level = 0;
        $sub = $this->category_tree[$categories_id]['sub'];
        if(isset($this->category_tree[$categories_id])){
            if($include_root && $categories_id > 0){
                $result .= "<$parent_tag class='level_$level $sub'><$child_tag class='level_$level $sub'>".$this->_build_category_string($categories_id,$parent_tag,$child_tag)."</$child_tag></$parent_tag>";
            }
            else{
                if(isset($this->category_tree[$categories_id]['sub_cats'])){
                    $result .= "<$parent_tag class='level_$level $sub'>";
                    foreach($this->category_tree[$categories_id]['sub_cats'] as $key => $value){
                        $sub = $this->category_tree[$value]['sub'];
                        $result .= "<$child_tag class='level_$level $sub'>".$this->_build_category_string($value,$parent_tag,$child_tag)."</$child_tag>";
                    }
                    $result .= "</$parent_tag>";
                }
            }

        }
        $result = str_replace(array('<>','</>'), '', $result);
        return $result;
    }

    function _build_category_string($categories_id = 0, $parent_tag = 'div', $child_tag = 'span', $level = 0){
        $result = $this->build_category_link($this->category_tree[$categories_id]['name'],$this->category_tree[$categories_id]['cPath']);
        $level++;
        $sub = $this->category_tree[$categories_id]['sub'];
        if(isset($this->category_tree[$categories_id]['sub_cats'])){
            $result .= "<$parent_tag class='level_$level $sub'>";
            foreach($this->category_tree[$categories_id]['sub_cats'] as $key => $value){
                $sub = $this->category_tree[$value]['sub'];
                $result .= "<$child_tag class='level_$level $sub'>".$this->_build_category_string($value,$parent_tag,$child_tag, $level)."</$child_tag>";
            }
            $result .= "</$parent_tag>";
        }
        return $result;
    }

    function build_category_link($categories_name, $cPath){
        return '<a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . $cPath) . '">'.$categories_name.'</a>';
    }
}

[yellow1912]

includes/auto_loaders/config.simple_categories_tree_generator.php

<?php
/**
 * ch_categories_tree_generator
 * @Version: 
 * @Authour: 
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 */ 
if (!defined('IS_ADMIN_FLAG')) {
    die('Illegal Access');
}
    $autoLoadConfig[0][] = array('autoType'=>'class', 'loadFile'=> 'simple_categories_tree_generator.php'); 
    $autoLoadConfig[180][] = array('autoType'=>'classInstantiate', 
                                  'className'=>'simple_categories_generator', 
                                  'objectName'=>'category_tree',
                                  'checkInstantiated'=>true,
                                  'classSession'=>true);
    
?>

[yellow1912]

A version that let you specify the depth level of the tree:

i.e: To print out just all the top categories:

<?php   
// 0 is the TOP node of the tree, and 1 is the max_level, so print only categories below 0, and go only 1 level deep.
echo $_SESSION['category_tree']->build_category_string('ul','li',0, 1);
 ?>

NOTE: Level should be greater than 0, I did not put a check there since I assume you should know what you are doing.

<?php
/**
 * Simple Category Tree
 * @Version: Beta 1
 * @Authour: yellow1912
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 */ 

define ('SCT_REBUILD_TREE','false');
class simple_categories_generator{
    var $category_tree = array();

    function simple_categories_generator() {
        if(SCT_REBUILD_TREE != 'false' || count($this->category_tree) == 0){
            global $languages_id, $db;
            $categories_query = "select c.categories_id, cd.categories_name, c.parent_id
                          from " . TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd
                          where c.categories_id = cd.categories_id
                          and c.categories_status=1
                          and cd.language_id = '" . (int)$_SESSION['languages_id'] . "'
                          order by c.parent_id, c.sort_order, cd.categories_name";
            $categories = $db->Execute($categories_query);
    
            while (!$categories->EOF) {
                $this->category_tree[$categories->fields['categories_id']] = array('name' => $categories->fields['categories_name'],
                'parent_id' => $categories->fields['parent_id']);
                $this->category_tree[$categories->fields['categories_id']]['path'][] = $categories->fields['categories_id'];
                $this->category_tree[$categories->fields['parent_id']]['sub_cats'][] = $categories->fields['categories_id'];
                if($categories->fields['parent_id'] > 0){
                    $this->category_tree[$categories->fields['categories_id']]['path'] = array_merge($this->category_tree[$categories->fields['parent_id']]['path'],$this->category_tree[$categories->fields['categories_id']]['path']);
                }
                $this->category_tree[$categories->fields['categories_id']]['cPath'] = implode('_',$this->category_tree[$categories->fields['categories_id']]['path']);        
                $categories->MoveNext();
            }
            // add sub 'class' for print-out purpose
            foreach($this->category_tree as $key => $value){
                $this->category_tree[$key]['sub'] = isset($this->category_tree[$key]['sub_cats']) ? 'has_sub' : 'no_sub';            
            }    
        }
    }

    // 9 is a ridiculous level already. If you go deeper than that, you have some problem with performance + structure
    // Max level should be around 3
    function build_category_string($parent_tag = 'div', $child_tag = 'span', $categories_id = 0, $max_level = 9, $include_root = false){
        if(!is_int($categories_id)){
            $temp = explode('_',$categories_id);
            $categories_id = $temp(count($temp)-1);
        }
        $result = '';
        $level = 0;
        $sub = $this->category_tree[$categories_id]['sub'];
        // don't check if max_level = 0, since we assume store owners are not crazy enough to do that
        // --> less check = faster
        if(isset($this->category_tree[$categories_id])){
            if($include_root && $categories_id > 0){
                $result .= "<$parent_tag class='level_$level $sub'><$child_tag class='level_$level $sub'>".$this->_build_category_string($categories_id,$parent_tag,$child_tag,$level,$max_level)."</$child_tag></$parent_tag>";
            }
            else{
                if(isset($this->category_tree[$categories_id]['sub_cats'])){
                    $result .= "<$parent_tag class='level_$level $sub'>";
                    foreach($this->category_tree[$categories_id]['sub_cats'] as $key => $value){
                        $sub = $this->category_tree[$value]['sub'];
                        $result .= "<$child_tag class='level_$level $sub'>".$this->_build_category_string($value,$parent_tag,$child_tag,$level,$max_level)."</$child_tag>";
                    }
                    $result .= "</$parent_tag>";
                }
            }
            $result = str_replace(array('<>','</>'), '', $result);
        }
        return $result;
    }

    function _build_category_string($categories_id = 0, $parent_tag = 'div', $child_tag = 'span', $level = 0, $max_level = 9){
        $result = $this->build_category_link($this->category_tree[$categories_id]['name'],$this->category_tree[$categories_id]['cPath']);
        $level++;
        if($level < $max_level){        
            $sub = $this->category_tree[$categories_id]['sub'];
            if(isset($this->category_tree[$categories_id]['sub_cats'])){
                $result .= "<$parent_tag class='level_$level $sub'>";
                foreach($this->category_tree[$categories_id]['sub_cats'] as $key => $value){
                    $sub = $this->category_tree[$value]['sub'];
                    $result .= "<$child_tag class='level_$level $sub'>".$this->_build_category_string($value,$parent_tag,$child_tag, $level,$max_level)."</$child_tag>";
                }
                $result .= "</$parent_tag>";
            }
        }
        return $result;
    }

    function build_category_link($categories_name, $cPath){
        return '<a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . $cPath) . '">'.$categories_name.'</a>';
    }
}

[yellow1912]

A new version with code improvement, and the ability to insert a delimiter between the children.

<?php
/**
 * Simple Category Tree
 * @Version: Beta 1
 * @Authour: yellow1912
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 */ 

define ('SCT_REBUILD_TREE','false');
class simple_categories_generator{
    var $category_tree = array();
    var $parent_open_tag = '';
    var $parent_close_tag = '';
    var $child_open_tag = '';
    var $child_close_tag = '';
    function simple_categories_generator() {
        if(SCT_REBUILD_TREE != 'false' || count($this->category_tree) == 0){
            global $languages_id, $db;
            $categories_query = "select c.categories_id, cd.categories_name, c.parent_id
                          from " . TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd
                          where c.categories_id = cd.categories_id
                          and c.categories_status=1
                          and cd.language_id = '" . (int)$_SESSION['languages_id'] . "'
                          order by c.parent_id, c.sort_order, cd.categories_name";
            $categories = $db->Execute($categories_query);
    
            while (!$categories->EOF) {
                $this->category_tree[$categories->fields['categories_id']] = array('name' => $categories->fields['categories_name'],
                'parent_id' => $categories->fields['parent_id']);
                $this->category_tree[$categories->fields['categories_id']]['path'][] = $categories->fields['categories_id'];
                $this->category_tree[$categories->fields['parent_id']]['sub_cats'][] = $categories->fields['categories_id'];
                if($categories->fields['parent_id'] > 0){
                    $this->category_tree[$categories->fields['categories_id']]['path'] = array_merge($this->category_tree[$categories->fields['parent_id']]['path'],$this->category_tree[$categories->fields['categories_id']]['path']);
                }
                $this->category_tree[$categories->fields['categories_id']]['cPath'] = implode('_',$this->category_tree[$categories->fields['categories_id']]['path']);        
                $categories->MoveNext();
            }
            // add sub 'class' for print-out purpose
            foreach($this->category_tree as $key => $value){
                $this->category_tree[$key]['sub'] = isset($this->category_tree[$key]['sub_cats']) ? 'has_sub' : 'no_sub';            
            }    
        }
    }

    // 9 is a ridiculous level already. If you go deeper than that, you have some problem with performance + structure
    // Max level should be around 3
    function build_category_string($parent_tag = 'div', $child_tag = 'span', $divider = '', $categories_id = 0, $max_level = 9, $include_root = false){
        if(!is_int($categories_id)){
            $temp = explode('_',$categories_id);
            $categories_id = $temp(count($temp)-1);
        }
        
        $result = '';
        // don't check if max_level = 0, since we assume store owners are not crazy enough to do that
        // --> less check = faster
        if(isset($this->category_tree[$categories_id])){
            // 
            $sub = $this->category_tree[$categories_id]['sub'];
            $level = 0;
            $class = "level_$level $sub";
            $this->_build_tags($parent_tag, $child_tag);
            // check if we should include the root or only its branches
            if($include_root && $categories_id > 0){
                $result = sprintf($this->parent_open_tag, $class).sprintf($this->child_open_tag, $class);
                $result .= $this->_build_category_string($categories_id, $level, $max_level, $divider);
                $result .= $this->child_close_tag.$this->parent_close_tag;
            }
            else{
                $result .= $this->__build_category_string($categories_id, $level, $max_level, $divider);
            }
            
        }
        return $result;
    }

    function _build_category_string($categories_id, $level, $max_level, $divider){        
        $result = $this->build_category_link($this->category_tree[$categories_id]['name'],$this->category_tree[$categories_id]['cPath']);
        $level++;
        $result .= $this->__build_category_string($categories_id, $level, $max_level, $divider);
        return $result;
    }

    function __build_category_string($categories_id, $level, $max_level, $divider){
        $result = '';
        if($level < $max_level){        
            $sub = $this->category_tree[$categories_id]['sub'];
            $class = "level_$level $sub";
            if(isset($this->category_tree[$categories_id]['sub_cats'])){
                    $result .= sprintf($this->parent_open_tag, $class);
                    $count = count($this->category_tree[$categories_id]['sub_cats']);
                    for($i=0; $i < $count; $i++){
                        $sub = $this->category_tree[$value]['sub'];
                        $class = "level_$level $sub";
                        $result .= sprintf($this->child_open_tag, $class).$this->_build_category_string($this->category_tree[$categories_id]['sub_cats'][$i],$level,$max_level, $divider).$this->child_close_tag;
                        $result .= ($i < ($count-1)) ? $divider : '';
                    }
                    $result .= $this->parent_close_tag;
                }
        }
        return $result;
    }
    
    function _build_tags($parent_tag, $child_tag){
        if(!empty($parent_tag)){
            $this->parent_open_tag = "<$parent_tag class='%s'>";
            $this->parent_close_tag = "</$parent_tag>";        
        }
        else{
            $this->parent_open_tag = $this->parent_close_tag = '';        
        }
        if(!empty($child_tag)){
            $this->child_open_tag = "<$child_tag class='%s'>";
            $this->child_close_tag = "</$child_tag>";        
        }
        else{
            $this->child_open_tag = $this->child_close_tag = '';
        }
    }
    
    function build_category_link($categories_name, $cPath){
        return '<a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . $cPath) . '">'.$categories_name.'</a>';
    }
}

[quentinjs]

This looks very cool, and might solve my problem. One question is you showed a line to show how it works, but where would someone put this within the zc files?

and I want to show the first 2 levels all the time, but still allow the user to dig in deeper in the sub cat they are interested in, will tis still allow that?

[yellow1912]

1. but where would someone put this within the zc files?
--> Put it any place you want to show the navigation bar

2. and I want to show the first 2 levels all the time, but still allow the user to dig in deeper in the sub cat they are interested in, will tis still allow that?

You can, just do something like this for instance:

<?php   echo $_SESSION['category_tree']->build_category_string('ul','li','',isset($_GET['cPath'])?$_GET['cPath']:0, 2);?>

The sample code above does something like this:
If cPath (categories_id) is on the link, then use that as a root, otherwise use 0 (the root of the tree).

[quentinjs]

Both classes/simple_categories_tree_generator.php examples are missing the end PHP tag.

As well I've dropped both files in place, fixed the end tag, but zencart dies. Remove the auto load and all is fine again.

I should also mention I've not put in any code to actually execute the display, only added the 2 files.

[yellow1912]

The forum dropped the end tags for some reason, anyway, you need to turn on strict error report to see what went wrong.

https://www.zen-cart.com/tutorials/index.php?article=82

[quentinjs]

Here is what I get with the debug tool.

[11-Feb-2008 02:22:00] PHP Warning: array_merge() [<a href='function.array-merge'>function.array-merge</a>]: Argument #1 is not an array in

includes\classes\simple_categories_tree_generator.php on line 35

[11-Feb-2008 02:22:00] PHP Warning: implode() [<a href='function.implode'>function.implode</a>]: Invalid arguments passed in includes\classes\simple_categories_tree_generator.php on line 37

hope this helps.

[yellow1912]

Do you see any fatal error? Warning should not be a problem

The updated code below should fix the first warning, the second warning should never happen though, weird.

<?php
/**
 * Simple Category Tree
 * @Version: Beta 1
 * @Authour: yellow1912
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 */ 

define ('SCT_REBUILD_TREE','false');
class simple_categories_generator{
    var $category_tree = array();
    var $parent_open_tag = '';
    var $parent_close_tag = '';
    var $child_open_tag = '';
    var $child_close_tag = '';
    function simple_categories_generator() {
        if(SCT_REBUILD_TREE != 'false' || count($this->category_tree) == 0){
            global $languages_id, $db;
            $categories_query = "select c.categories_id, cd.categories_name, c.parent_id
                          from " . TABLE_CATEGORIES . " c, " . TABLE_CATEGORIES_DESCRIPTION . " cd
                          where c.categories_id = cd.categories_id
                          and c.categories_status=1
                          and cd.language_id = '" . (int)$_SESSION['languages_id'] . "'
                          order by c.parent_id, c.sort_order, cd.categories_name";
            $categories = $db->Execute($categories_query);
    
            while (!$categories->EOF) {
                $this->category_tree[$categories->fields['categories_id']] = array('name' => $categories->fields['categories_name'],
                'parent_id' => $categories->fields['parent_id']);
                $this->category_tree[$categories->fields['categories_id']]['path'][] = $categories->fields['categories_id'];
                $this->category_tree[$categories->fields['parent_id']]['sub_cats'][] = $categories->fields['categories_id'];
                if($categories->fields['parent_id'] > 0){
                    if(!isset($this->category_tree[$categories->fields['parent_id']]['path']))
                        $this->category_tree[$categories->fields['parent_id']]['path'] = array();
                    elseif(count($this->category_tree[$categories->fields['parent_id']]['path'])> 0)
                        $this->category_tree[$categories->fields['categories_id']]['path'] = array_merge($this->category_tree[$categories->fields['parent_id']]['path'],$this->category_tree[$categories->fields['categories_id']]['path']);
                }
                $this->category_tree[$categories->fields['categories_id']]['cPath'] = implode('_',$this->category_tree[$categories->fields['categories_id']]['path']);        
                $categories->MoveNext();
            }
            // add sub 'class' for print-out purpose
            foreach($this->category_tree as $key => $value){
                $this->category_tree[$key]['sub'] = isset($this->category_tree[$key]['sub_cats']) ? 'has_sub' : 'no_sub';            
            }    
        }
    }

    // 9 is a ridiculous level already. If you go deeper than that, you have some problem with performance + structure
    // Max level should be around 3
    function build_category_string($parent_tag = 'div', $child_tag = 'span', $divider = '', $categories_id = 0, $max_level = 9, $include_root = false){
        if(!is_int($categories_id)){
            $temp = explode('_',$categories_id);
            $categories_id = $temp(count($temp)-1);
        }
        
        $result = '';
        // don't check if max_level = 0, since we assume store owners are not crazy enough to do that
        // --> less check = faster
        if(isset($this->category_tree[$categories_id])){
            // 
            $sub = $this->category_tree[$categories_id]['sub'];
            $level = 0;
            $class = "level_$level $sub";
            $this->_build_tags($parent_tag, $child_tag);
            // check if we should include the root or only its branches
            if($include_root && $categories_id > 0){
                $result = sprintf($this->parent_open_tag, $class).sprintf($this->child_open_tag, $class);
                $result .= $this->_build_category_string($categories_id, $level, $max_level, $divider);
                $result .= $this->child_close_tag.$this->parent_close_tag;
            }
            else{
                $result .= $this->__build_category_string($categories_id, $level, $max_level, $divider);
            }
            
        }
        return $result;
    }

    function _build_category_string($categories_id, $level, $max_level, $divider){        
        $result = $this->build_category_link($this->category_tree[$categories_id]['name'],$this->category_tree[$categories_id]['cPath']);
        $level++;
        $result .= $this->__build_category_string($categories_id, $level, $max_level, $divider);
        return $result;
    }

    function __build_category_string($categories_id, $level, $max_level, $divider){
        $result = '';
        if($level < $max_level){        
            $sub = $this->category_tree[$categories_id]['sub'];
            $class = "level_$level $sub";
            if(isset($this->category_tree[$categories_id]['sub_cats'])){
                    $result .= sprintf($this->parent_open_tag, $class);
                    $count = count($this->category_tree[$categories_id]['sub_cats']);
                    for($i=0; $i < $count; $i++){
                        $sub = $this->category_tree[$value]['sub'];
                        $class = "level_$level $sub";
                        $result .= sprintf($this->child_open_tag, $class).$this->_build_category_string($this->category_tree[$categories_id]['sub_cats'][$i],$level,$max_level, $divider).$this->child_close_tag;
                        $result .= ($i < ($count-1)) ? $divider : '';
                    }
                    $result .= $this->parent_close_tag;
                }
        }
        return $result;
    }
    
    function _build_tags($parent_tag, $child_tag){
        if(!empty($parent_tag)){
            $this->parent_open_tag = "<$parent_tag class='%s'>";
            $this->parent_close_tag = "</$parent_tag>";        
        }
        else{
            $this->parent_open_tag = $this->parent_close_tag = '';        
        }
        if(!empty($child_tag)){
            $this->child_open_tag = "<$child_tag class='%s'>";
            $this->child_close_tag = "</$child_tag>";        
        }
        else{
            $this->child_open_tag = $this->child_close_tag = '';
        }
    }
    
    function build_category_link($categories_name, $cPath){
        return '<a href="' . zen_href_link(FILENAME_DEFAULT, 'cPath=' . $cPath) . '">'.$categories_name.'</a>';
    }
?>
}