I am trying to create a multidimensional array of my navigation. All my pages are created in a CMS and then stored in my DB. Each page will have the usual fields like title, url etc but also they will have a field which tells me if it has any children 'p_has_children' as well as a field which will tell me its parent page 'p_parent' (if it is a child of a page).
I thought I could write a function which I could call and send it an array of all the top level navigation items. Then as I loop through each item I would check if it had any children, get the children (and assign them to an array) and then send them through the same function like so....
function sideNavArray()
{
//Get the side navigation
$getSidenav = $this->crud_model->fetch_rows_where('pages', array('p_side_nav' => 'y', 'p_active' => 'y'));
//Call the navbuilder function
$sidenav = $this->sidenavBuilder($getSidenav, 'navitem', 'nav');
//return the generated nav
return $sidenav;
}
function sidenavBuilder($navItems, $itemClass, $navLevel, $i = 0, $sidenav = array())
{
//Loop over each nav item
foreach($navItems as $navItem){
//For each item I want to add th nav_title, slug, url and page type
$sidenav[$i]['p_nav_title'] = $navItem->p_nav_title;
$sidenav[$i]['p_slug'] = $navItem->p_slug;
$sidenav[$i]['p_url'] = $navItem->p_title;
$sidenav[$i]['p_type'] = $navItem->p_type;
//See if this page has any children
if($navItem->p_has_children == 'y'){
//If the page has children then I want to fetch them from the DB
$subnav = $this->crud_model->fetch_rows_where('pages', array('p_parent' => $navItem->id, 'p_active' => 'y', 'p_protected !=' => 'y'));
if(!empty($subnav)){
//Change the item class and level to subnavitem and subnav
$itemClass = 'sub' . $itemClass;
$navLevel = 'sub' . $navLevel;
//Assign the children to the same array as its parent in the "subnav" level and send it through the sitenavBuilder function
$sidenav[$i][$navLevel] = $this->sitenavBuilder($subnav, $itemClass, $navLevel);
}
}
$i++;
//End foreach loop
}
return $sidenav;
}
I am sure some of you are looking at this right now and saying well of course that won't work!
I currently have a navigation being generated but it is on the front end and every time I want to add an additional level I have to go into the code and add it manually. I want to avoid having to write each level of the navigation as I want it to be able to grow to as many levels as it can without me having to go in and code that extra level if it is needed every time.
I hope this all makes sense. Basically I want to know if there is a way to get this nav array to be built by running through the same loop over and over until it doesn't need to anymore.
This one is a little tough,
I have imported a list of products from ACTINIC to a mysql database. I need to be able to collect all products from a top level menu item and put all of the child menu items in an array so i can look up which products belong to said top level item.
All the menu items have id's that are sequential starting from 1.
i need a way of looping through an undetermined amount of child items based on their parent id's and to collect all of there id's into an array to be used to loop up the products.
I think i have explained that well enough, any help or ideas would be great. Just need a starting point then i can go from here.
// EDIT
Thanks johan for pointing me in the right direction
// $all is a mysql query
loopit($all);
function loopit($array){
while($forone = mysql_fetch_array($array)){
echo "id=" . $forone['nSectionID'] . " name=" . $forone['Section text'] . "<br />";
$seltwo = mysql_query("SELECT * FROM [table] WHERE nParentSectionID='" . $forone['nSectionID'] . "'");
loopit($seltwo);
}
}
You will need a recursive function for that. Something like this:
function import ( $items ) {
foreach ( $items as $item ) {
// handle item import
// .....
if ( $item->children ) {
import( $item->children ); // Notice the function calling itself here.
}
}
}
Im looking for a way to extract the data from the mysql database to create an unlimited subcategry menu.
The menu has about 1500 categories in it and they are stored into the database table (menu) in the following format :
category_id , category title , parent_id
i want to do 1 mysql query to put all the data into an array.
$menu_list =array();
$query = mysql_query("SELECT * FROM menu ORDER BY category_id ASC");
if(mysql_num_rows($query) != 0) {
while($row = mysql_fetch_array($query)){
$category_id = $row['category_id'];
$title = $row['category_title'];
$parent_id = $row[parent_id'];
$menu_list[] = array($category_id,$title,$parent_id);
}
}
That is the code that i am currently using to turn the data into the array.
I then need to loop through the array to build a menu up.
I will then hide all subcategories and expand with jquery ( I can do this bit no problem )
The problem i have is going through the array and displaying the data in the right order.
The menu has unlimited subcategories so it will probably need to be a recursive function to retrieve the data.
I have folllowed alot of the examples on here but then i get lost how to display the data..
i now need to end up with :
main item
sub cat
sub cat
sub cat
sub cat
main item
sub cat
main item
main item
sub cat
sub cat
sub cat
sub cat
sub cat
etc...
with each category in its own div
I will then need to be able to edit each category (ie title name and position if need be)
then if i change where a sub category is based a quick page refresh will reload the menu in the new order..
eventually i would like to make this into a drag and drop but that will be at a later date.
I hope this has explained it enough..
Thanks in advance..
So the problem has come back to haunt me again...
My method of ajax calling another mysql select was ok for the CMS section as it was only used from time to time.
But now we have got to the front end.
Each time the page is viewed the first 3 levels of the menu are pulled using numerous mysql requests.
As the categories are getting bigger this is now resulting in 1600+ categories being pulled numerous times each, and even at 1000 visits a day will result in more than a 1000000 sql requests a day.
So i think i will definately need to pull the categories into an array, and then recursively go through the array.
I have looked at the solutions above and they seem to work on paper but not in practise.
If anyone can attempt to give me another solution it would be appreciated..
just to recap in my db i have : id , category_name , parent_id
I am now using PDO with mysql and prepared statements for added security..
Thanks in advance..
Here is the code what you need
category_id AS id , category title AS kategori and parent_id AS kid
function countsubcat($pid)
{
$r=mysql_query("select count(kid) AS say from meskat where kid='$pid' limit 1");
$rw=mysql_fetch_array($r);
return $rw['say'];
}
function listmenu($pid = 0)
{
$res = mysql_query("select id,kategori,kid from meskat where kid='$pid'");
while($cat=mysql_fetch_array($res))
{
echo '<li>';
print''.$cat['kategori'].'';
if(countsubcat($cat['id'])>0)
{
print'<ul>';
listmenu($cat['id']);
print'</ul>';
}
echo '</li>';
}
}
echo '<ul>';
listmenu(0); //starting from base category
echo '</ul>';`
In MySQL, this will require many queries, one for each level plus one at a minimum.
you grab all the top-level categories, use them as root nodes for a forest (a group of trees).
You grab all of the categories that are children of any of them.
Add each of these categories as children to the parent node
If there are still children, go to step two, otherwise stop.
What you end up with a tree that you do a depth-first walk through to convert to some (presumably) html representation (e.g. nested lists).
There are some optimisations you can perform. If you sort the child levels by parent ID, then you can assume continuous blocks of children, meaning you don't have to do as many lookups to find the correct parent, just check for a parent id change.
If you maintain a list of the current lowest level of categories, indexed by ID, you can speed up forest creation.
If you overlap steps 2 and 4, then you only do n+1 queries (where n is the number of levels), so checking for more children is also grabbing the next level of children.
In terms of memory, this will use the memory required for the tree, plus lowest level lookup table and a current parent id.
The building algorithm it fairly fast, scaling linearly with the number of categories.
This method also successfully avoids corrupted sections of data, because it won't grab data that have cycles (no root node).
I also suggest using a prepared statement for the children query, since MySQL will compile and cache the query, it will speed up the operation by only sending new data across the wire.
If you don't understand some of the concepts, I suggest hitting up Wikipedia as I have tried to use standard terms for these.
Can you alter the table structure? In that case you could take a look at the Nested Set Model (link includes description and implementation details, scroll down to The Nested Set Model). Node insertion and removal becomes more complex, but allows you to retrieve the whole tree in just one query.
If you can assume that for any category category_id > parent_id is true, the following recursive functions to represent the menu as a multi-level array and render it as a nested HTML list would work:
$menu = array();
$query = mysql_query("SELECT category_id, category_title, parent_id FROM menu ORDER BY category_id ASC");
if(mysql_num_rows($query) != 0) {
while($row = mysql_fetch_assoc($query)) {
if(is_null($row['parent_id']))
$menu['children'][] = $row;
else
add_to_menu(&$menu,$row);
}
}
function add_to_menu($menu,$item) {
if(isset($menu['children'])) {
foreach($menu['children'] as &$child) {
if($item['parent_id'] == $child['category_id']) {
$child['children'][] = $item;
} else {
add_to_menu(&$child,$item);
}
}
}
}
function render_menu($menu) {
if(isset($menu['children'])) {
echo '<ul>';
foreach($menu['children'] as &$child) {
echo "<li>";
echo $child['category_id']." : ".$child['category_title'];
if(isset($child['children'])) {
render_menu(&$child);
}
echo "</li>";
}
echo '</ul>';
}
}
render_menu($menu);
So after various attempts at different solutions i actually have used jquery and a ajax load to retreive the next level.
With mine main categories all have a parent of 1 - shop i do a mysql scan for all categories with 1 as the parent id.
This will then display the main categories. Attached to each main category i have added a folder icon if they have any sub categories.
I have also inserted a blank div with an id of that category.
When the folder is clicked it does an ajax call to a php script to find all categories with that parent. These are appended to the parents_id div.
This inturn adds the category (with a css padding to indicate a sub category) and again a folder sign if it has sub categories as well as another blank div with the category_id.
You can continue this for as many categories and sub categories as the client requires.
I took it a stage further and added an edit icon to category/subcategory so categories can be moved or changed.
If you would like some sample code for this let me know...
Actually, you need very little code to build a tree.
You also only need one query.
Here is what I came up with (I use Drupal's database but it is explicit enough to understand):
$items = db_select('menu_items', 'mi')
->fields('mi')
->orderBy('position')
->execute()
->fetchAllAssoc('id', PDO::FETCH_ASSOC);
// Example of result. The ID as key is important for this to work.
$items = array(
3 => array('id' => 3, 'parent' => NULL, 'title' => 'Root', 'position' => 0),
4 => array('id' => 4, 'parent' => 3, 'title' => 'Sub', 'position' => 0),
5 => array('id' => 5, 'parent' => 4, 'title' => 'Sub sub', 'position' => 0),
6 => array('id' => 6, 'parent' => 4, 'title' => 'Sub sub', 'position' => 1),
);
// Create the nested structure. Note the & in front of $item.
foreach($items as &$item)
if($item['parent'])
$items[$item['parent']]['sub items'][$item['mid']] =& $item;
// Now remove the children from the root
foreach($items as $id => $item)
if($item['parent']) // This is a child
unset($items[$id])
At this point, all you need is a recursive function to display the menu:
function print_menu($items) {
echo '<ul>';
foreach($items as $item) {
echo '<li>';
echo '' . $item['title'] . '';
if(!empty($item['sub items']))
print_menu($item['sub items']);
echo '</li>';
}
echo '</ul>';
}
I have list of items that need to be processed and printed to the user.
Each item on the list needs to have a unique set of calculations to it.
The only thing is, the user also supplies me with the order of how items will be printed & handled first - for example: item4,item2,item1,item3
How can one approach this in PHP?
I thought of running a for loop against the user submitted ordered list and tackle each calculation and print it to the user, the problem is that this will be hard to maintain because the user will have to edit the for loop each time he will want to add a new item or calculation.
Given a list of 1-n items:
$items['item1'] = $item1;
With a co-related list of 1-n functions:
$functions['item1'] = function($item) {return ...;};
You can sort items according to the user-input:
$subset = orderAndFilterItems($items, $userInput);
and then iterate:
foreach($subset as $key => $item)
{
$function = $functions[$key];
$value = $function($item);
}
Naturally you can encapsulate this further on, but it should give you the idea.
I want to get all of the SiteTree pages of a Silverstripe website and then sort them by depth descending. By depth I mean the number of parents they have.
This is already done to some extent by the Google Sitemaps Module. Except it doesn't go past a depth of 10 and doesn't calculate for pages hidden from search: https://github.com/silverstripe-labs/silverstripe-googlesitemaps
Looking at the Google Sitemaps Module module it appears easy enough to count the number of parents of a page: ( /code/GoogleSitemapDecorator.php - line 78)
$parentStack = $this->owner->parentStack();
$numParents = is_array($parentStack) ? count($parentStack) - 1: 0;
But what is the best way to sort the SiteTree using this calculation?
I'm hoping there's an easier way than getting all of the SiteTree, appending the depth, and then resorting.
The function below will get all published pages from the database, checks they are viewable and not an error page, finds out how many ancestors they have and then returns a DataObjectSet of the pages ordered by depth (number of ancestors).
public function CustomPages() {
$filter = '';
$pages = Versioned::get_by_stage('SiteTree', 'Live', $filter);
$custom_pages = new DataObjectSet();
if($pages) {
foreach($pages as $page) {
if( $page->canView() && !($page instanceof ErrorPage) ) {
$parentStack = $page->parentStack();
$numParents = is_array($parentStack) ? count($parentStack) - 1 : 0;
$page->Depth = $numParents;
$custom_pages->push($page);
}
}
}
$custom_pages->sort('Depth', 'DESC');
return $custom_pages;
}
If you're using PostgreSQL you can also use a single database query. In our effort to speed up SilverStripe (2.4), we've replaced the getSiteTreeFor() with a single database query, see:
http://fvue.nl/wiki/SilverStripe:_Replace_getSiteTreeFor_with_single_query
The breadcrumb field contains an array of ID's on which you can sort.