How do I loop through a sliced array?

[phil_s]

I am finishing up my first processwire site (yay), and this last bit is giving me a bit of a headache:
For a news slider, I want to output x number of posts, with three posts per slide. (for a theoretically unlimited number of slides)

I figure in theory this should work something like the code below, however the looping logic, among other things is still somewhat beyond me:

<?php
    $items_per_page = 3;
    $start = ($pages->get("/news/")->find("sort=sort")->pageNum - 1) * $items_per_page;
    $total = count($pages->get("/news/")->find("sort=sort"));
    $slicedarticles = $pages->get("/news/")->find("sort=sort")->slice($start, $items_per_page);
    
    foreach ($slicedarticles as $slicedarticle => $total) {
        echo "<div class='slide'>";
        
        foreach ($slicedarticle as $article) {
            echo "<h3>{$article->title}</h3><p>{$article->body}</p>";
        }
        
    echo "</div>";
    }
?>

Can someone point me in the right direction with this?

Much appreciated!

Cheers,

Phil

[apeisa]

Not sure what kind of markup you are after, but getting and looping three posts is simple as this:

$articles = $pages->find("parent=/news/, limit=3");

foreach($articles as $article) {
  echo "<div class='slide'>$article->title</div>";
}

[phil_s]

@apeisa, sorry, edited the initial post to make this more clear:

I want to output x number of posts, and "package" them into slides (each slide containing three posts).

Makes more sense?

[diogo]

Hm, there are several things to correct in your code. First one, and most important, is that slice() will give you only one array

$a->slice($n, $limit) -> Returns a new WireArray containing a slice of items starting from the $n'th item and including up to $limit number of items.

and I don't think this is what you are looking after.

Second one, is the way you are using the => sign in your foreach. When you do "$slicedarticle => $total", what will happen is that $slicedarticle will be populated the key of this element, and $total will be the value of the element. So, the content that you had on these variables will simply be lost. Read here http://php.net/manual/en/control-structures.foreach.php

What I interpret that you want, is to create the amount of slides needed so you have only three elements on each slide. Is that right? If so, try this:

$items_per_page = 3;

$myPages = $pages->get(1)->find('sort=sort');

$nrSlides = count($myPages)/$items_per_page;

while($nrSlides > 0) {

    echo "<div class='slide'>";

        for($i=$items_per_page; $i>0; $i--) {
            
            if(count($myPages)) {
         
                $article = $myPages->shift();

                echo "<h3>{$article->title}</h3><p>{$article->id}</p>";

            }

        }

    echo "</div>";

    $nrSlides--;
}
 

Edit: By your new explanation, I think this is what you want

Also, look for shift() on the cheatsheet http://cheatsheet.processwire.com/ to understand what's happening in my code:

Remove (shift) the first $item from the WireArray and return it.

Edit2: changed the if statement in the code for something better

[apeisa]

@apeisa, sorry, edited the initial post to make this more clear:

I want to output x number of posts, and "package" them into slides (each slide containing three posts).

Makes more sense?

$articles = $pages->find("parent=/news/, limit=18");

$out = '';
foreach ($articles as $key => $article) {
  if ($key == 0) $out .= "<div class='slide first'>"; // Open the first .slide
  else if ($key % 3 == 0) $out .= "</div><div class='slide'>"; // Close the previous slide and open next
  $out .= "<div class='post'><h2>$article->title</h2></div>"; // render the actual markup
}
$out .= "</div>"; // Close the final .slide

echo $out;

not tested and written in browser. You can omit the limit if you want to.

[phil_s]

@Apeisa, just went through my old posts and noticed I never replied back! Sorry, and  thank you very much, this worked perfectly!

$articles = $pages->find("parent=/news/, limit=18");

$out = '';
foreach ($articles as $key => $article) {
  if ($key == 0) $out .= "<div class='slide first'>"; // Open the first .slide
  else if ($key % 3 == 0) $out .= "</div><div class='slide'>"; // Close the previous slide and open next
  $out .= "<div class='post'><h2>$article->title</h2></div>"; // render the actual markup
}
$out .= "</div>"; // Close the final .slide

echo $out;

not tested and written in browser. You can omit the limit if you want to.

[Ivan Gretsky]

Actually there is a solution for working with slice_array. The thing is that $pages->get("/news/")... returns a PageArray thing, which is not a php array, but probably an object (not sure).

But there is a way to get this data as a php array like this:

$array=$pages->get("/news/")->getArray();

This one you can slice.

And there is a native way to slice PageArray (diogo wrote about it):

$pages->get("/news/")->slice($n, $limit). Read about it here.