solved Simple categories filtering

[onjegolders]

I've been reading up on a few posts on categories but I'm struggling to get them working.

I saw a video from PW1

and the example seems nice and simple:

Output the categories, click one and the list of entries gets filtered.

I tried to replicate that but no joy. I can't seem to understand how Ryan can output $page->categories from his page when really the categories are surely part of children()?

Is it really possible to filter categories of events or news this simply? I've seen other examples in the forums which look much more complex (urlSegments and the like).

I currently have my category page set up as a child of home, and categories as its children.

Before seeing that video, I had managed to output the categories like this:

<div id="events_index_side">

<?php if ($pages->find("template=category")) { ?>

<div class="events_index_side_box">

<h5 class="page_header">By category</h5>

<ul>
<?php $categories = $pages->find("template=category");
foreach ($categories as $category) { ?>

<li><a href="<?php echo $page->url . $category->name; ?>"><?php echo $category->title; ?></a></li>

<?php }
?>
</ul>

</div><!-- /.events_index_side_box -->

<?php } ?>

but using this method, I'm not quite sure how I can get the page to reload with just those categorised entries?

Would appreciate if anyone could give me a shove in the right direction. Thanks.

[ryan]

if ($pages->find("template=category"))

The above will never resolve to false, so doesn't do anything. That's because find() returns a PageArray(). Think of it like a bottle that might have beer in it. An empty beer bottle is still a beer bottle. So you have to check if there's anything in it:

$categories = $pages->find("template=category"); 
if(count($categories)) {
   // there are categories
   foreach($categories) {
       // output category
   }
}

I suggest using a separate 'category' template to handle the display of a given category (rather than trying to do it all in your 'categories' template). Here's the code you might do it with in your category template. This assumes the categorized entries have a field called "categories"

$entries = $pages->find("categories=$page"); 
if(count($entries)) {
   echo "<ul>";
   foreach($entries as $entry) {
       echo "<li><a href='{$entry->url}'>{$entry->title}</a></li>";
   } 
   echo "</ul>";
} else {
   echo "<p>No entries in this category.</p>";
}

[onjegolders]

The above will never resolve to false, so doesn't do anything. That's because find() returns a PageArray(). Think of it like a bottle that might have beer in it. An empty beer bottle is still a beer bottle. So you have to check if there's anything in it:

$categories = $pages->find("template=category");
if(count($categories)) {
// there are categories
foreach($categories) {
	// output category
}
}

I suggest using a separate 'category' template to handle the display of a given category (rather than trying to do it all in your 'categories' template). Here's the code you might do it with in your category template. This assumes the categorized entries have a field called "categories"

$entries = $pages->find("categories=$page");
if(count($entries)) {
echo "<ul>";
foreach($entries as $entry) {
	echo "<li><a href='{$entry->url}'>{$entry->title}</a></li>";
}
echo "</ul>";
} else {
echo "<p>No entries in this category.</p>";
}

Thanks Ryan, that makes it clearer, though I'm still unsure what I should be doing on my events "index" page.

On the left I display all the events and in the sidebar I ideally wanted to list the categories and then on click, filter the entries (I suppose at events/category_name).

Sorry for being slow, just not quite sure how to link this up.

On your video example, you only seemed to have a small bit of code in one template which did all the magic!

[ryan]

On the left I display all the events and in the sidebar I ideally wanted to list the categories and then on click, filter the entries (I suppose at events/category_name).

If you want your events index to list all the categories, you could just do thi:

$categories = $pages->find("template=category, sort=name");

foreach($categories as $c) echo "<p><a href='{$c->url}'>{$c->title}</a></p>";

If you want to use URL segments to filter the listing of events by category, you could use URL segments with a URL structure like /events/category/cheese/. Then your events index could look for it like this:

if($input->urlSegment1 == 'category' && $input->urlSegment2) {
   $name = $sanitizer->pageName($input->urlSegment2);
   $category = $pages->get("template=category, name=$name"); 
   if($category->id) {
       $events = $pages->find("template=event, categories=$category"); 
       foreach($events as $event) echo "<p><a href='{$event->url}'>{$event->title}</a></p>"; 
   }
}

[onjegolders]

Thanks, have spent this morning trying to get this to work but I'm just not managing it unfortunately.

I've gone down the include route so that now, my event index page looks like this:

<?php include("./header.inc"); ?>

<?php if ($input->urlSegment1 != "") {
include ("./categories.inc");
} else { ?>

<div id="events_index_wrap" class="bg_gradient">

<div id="events_index_main">

<h3 class="page_header">Upcoming Events</h3>

<?php
$entries = $pages->find("template=event, sort=date");
$count = 0;

foreach ($entries as $event) {
$count++;
$class = "event_box";
if (0 == $count % 2) { $class .= " event_box_second"; }
?>

<div class="<?php echo $class; ?>">

<div class="event_box_text">
<h2><a href="<?php echo $event->url; ?>"><?php echo $event->title; ?></a></h2>
<h5><?php echo $event->date; ?></h5>
</div><!-- /.event_box_text -->
<div class="clear"></div>

<?php if ($event->images) {
$img = $event->images->first()->size(220,165);
?>
<a href="<?php echo $event->url; ?>"><img src="<?php echo $img->url; ?>" width="<?php echo $img->width; ?>" height="<?php echo $img->height; ?>" alt="<?php echo $entry->title; ?>" class="med_frame" /></a>
<?php } ?>

</div><!-- /.event_box -->

<?php }
?>

</div><!-- /#events_index_main -->

<div id="events_index_side">


<div class="events_index_side_box">

<?php if (count($pages->find("template=category"))) {
$category = $pages->find("template=category");
?>
<ul>
<?php foreach ($category as $cat) { ?>
<li><a href="<?php echo $page->url . $cat->name; ?>"><?php echo $cat->name; ?></a></li>
<?php } ?>
<?php } ?>

</div><!-- /.events_index_side_box -->

</div><!-- /#events_index_side -->

<div class="clear"></div>

</div><!-- /#events_index_wrap -->

<?php } ?>

<?php include("./footer.inc"); ?>

So on the category list, I tack on the category name to the url and if there's a URL segment it includes the categories include, which looks like:

<div id="events_index_wrap" class="bg_gradient">

<div id="events_index_main">

<h3 class="page_header">Upcoming Events - <?php echo $input->urlSegment1; ?></h3>

<?php
$name = $sanitizer->pageName($input->urlSegment1);
echo "<h1>$name</h1>";

$entries = $pages->find("template=event, categories=$name, sort=date");
$count = 0;

foreach ($entries as $event) {
$count++;
$class = "event_box";
if (0 == $count % 2) { $class .= " event_box_second"; }
?>

<div class="<?php echo $class; ?>">

<div class="event_box_text">
<h2><a href="<?php echo $event->url; ?>"><?php echo $event->title; ?></a></h2>
<h5><?php echo $event->date; ?></h5>

</div><!-- /.event_box_text -->
<div class="clear"></div>

<?php if ($event->images) {
$img = $event->images->first()->size(220,165);
?>
<a href="<?php echo $event->url; ?>"><img src="<?php echo $img->url; ?>" width="<?php echo $img->width; ?>" height="<?php echo $img->height; ?>" alt="<?php echo $entry->title; ?>" class="med_frame" /></a>
<?php } ?>

<?php $categories = $event->categories; foreach ($categories as $cg) { ?>
<h6><?php echo $cg->name; ?></h6>
<?php } ?>

</div><!-- /.event_box -->

<?php }
?>

</div><!-- /#events_index_main -->

<div id="events_index_side">


<div class="events_index_side_box">

<?php if (count($pages->find("template=category"))) {
$category = $pages->find("template=category");
?>
<ul>
<?php foreach ($category as $cat) { ?>
<li><a href="<?php echo $page->url . $cat->name; ?>"><?php echo $cat->name; ?></a></li>
<?php } ?>
<?php } ?>

</div><!-- /.events_index_side_box -->

</div><!-- /#events_index_side -->

<div class="clear"></div>

</div><!-- /#events_index_wrap -->

My issue is that I'm pretty sure that the category name is matching the urlSegment but when I choose a category the list comes up empty. I've thought of possible reasons (lower/upper case categories?), I've also tried to pass a variable to the current category but not to sure how to get that working before looping through the entries...

If anyone has any idea, that would be much appreciated, thanks.

[onjegolders]

This is one of those moments when I question what I'm doing with my life! Spend 7 hours today trying to figure out this one problem (sometimes I really think I would pay for commercial support )

Seems I should have been setting a $category variable and checking for name=$name (so essentially was missing a step) I must have spent about a million hours trying to figure that out...

One thing I can't seem to figure out though is how to only show links to categories that have been used once or more. Currently it is showing all categories, even if they're empty. The tiny logical part of my brain is saying that I should be referencing events and not categories

Something like:

$cats = $pages->find("template=event")->categories;

But can't seem to figure it out

[ryan]

If you are displaying categories and want to exclude any that don't have any events attached, then you could do this:

$categories = $pages->find("template=category"); 
foreach($categories as $category) {
   $numEvents = $pages->count("template=event, categories=$category"); 
   if($numEvents > 0) {
       // display category
   } else {
       // don't display category
   }
}

[onjegolders]

Thanks Ryan that works perfectly, have a nice evening!