Pagination fix after dropdown filter on Custom Taxonomy Archive WordPress

Rempty comments:

<form id="sale_selector" method="post" action="' . get_term_link($sale) . '">
to
<form id="sale_selector" method="get" action="' . get_term_link($sale) . '">

And change $_POST['section_name'] AND $_POST['sale_submit'] to $_GET['section_name'] $_GET['sale_submit']

theflyingant comments:

Thanks. Unfortunately doing it this way results in undefined variables ($first_lot & $last_lot) within the meta_query.

Rempty comments:

I modified your code take a look
Dropdown setup

function sale_selector() {
global $wp_query;

if(isset($_GET['sale_submit'])) {
$dropdown_value = $_GET['section_name'];
}
// Query for current sale name

$sale = $wp_query->get_queried_object();
$sale_id = $sale->term_id;
$acf_lookup = 'sale_'.$sale_id;

echo '<form id="sale_selector" method="get" action="' . get_term_link($sale) . '">
<select name="section_name">
<option value="">All Lots</option>';
if( have_rows('sections', $acf_lookup ) ){
while( have_rows('sections', $acf_lookup ) ): the_row();
$section_title = get_sub_field('sectionname');
if($section_title == $dropdown_value){
$selected = ' selected';
} else {
$selected = '';
}

echo '<option value="' . $section_title . '" ' . $selected . '>' . $section_title . '</option>'; // not sure selected is working properly here
endwhile;
}

echo '</select>
<input type="submit" name="sale_submit" id="filter_button" value="OK">
</form>';
}


The relevant part of pre_get_posts in your functions.php

if(is_tax('sale')&& $query->is_main_query()){
if(isset($_GET['sale_submit'])) {
$dropdown_selection = $_GET['section_name'];
// get all rows from the postmeta table where the sub_field (section_title) equals the dropdown selection
global $wpdb;

$section_rows = $wpdb->get_results( "
SELECT *
FROM {$wpdb->prefix}postmeta
WHERE meta_key LIKE 'sections_%_sectionname'
AND meta_value = '{$dropdown_selection}'
"
);



// loop through the results

if( $section_rows ){
foreach( $section_rows as $section_row ){
// for each result, find the 'repeater row number' and use it to load the sub fields
preg_match('_([0-9]+)_', $section_row->meta_key, $matches);
$meta_key1 = 'sections_' . $matches[0] . '_firstlot'; // $matches[0] contains the row number
$meta_key2 = 'sections_' . $matches[0] . '_lastlot';

// use get_post_meta to load the image sub field
$first_lot = get_post_meta( $section_row->post_id, $meta_key1, true );
$last_lot = get_post_meta( $section_row->post_id, $meta_key2, true );

}

}



$query->set( 'meta_query', array(
'relation' => 'AND',
array(
'key' => 'online_lot_number',
'compare' => '>=',
'type' => 'NUMERIC',
'value' => $first_lot // first number in the section from ACF repeater field.

),
array(
'key' => 'online_lot_number',
'compare' => '<=',
'type' => 'NUMERIC',
'value' => $last_lot // last number in the section from ACF repeater field.
),
));

}
}


theflyingant comments:

Thanks, unfortunately still getting the undefined variables for the 'value' part of the meta_query.

Rempty comments:

Check you url parameters after send the form

must be like myurl.com/term_slug/?sale_submit=ok&section_name=valuexyz

theflyingant comments:

?section_name=Perfumes&sale_submit=OK is correctly appended to end of url.

Rempty comments:

check the querys
inside if(is_tax('sale')&& $query->is_main_query()){

First echo $_GET['section_name'] and check the value
echo $dropdown_selection = $_GET['section_name'];

check the results of $section_rows

theflyingant comments:

$_GET['section_name'] returns undefined index error.

since switching from $_POST to $_GET, section rows now returns empty array. It worked with $_POST.

Rempty comments:

Plz test echo $_GET['sale_submit'] ;
If don't show error "undefined....";

Try changing the name of the select to other maybe like section_namex, don't forget to replace the name new in all $_GET['section_name'];

If show the error undefined
add this to your functions.php

add_filter( 'query_vars', 'addnew_query_vars', 10, 1 );
function addnew_query_vars($vars)
{
$vars[] = 'section_name';
$vars[] = 'sale_submit';
return $vars;
}


theflyingant comments:

The undefined index was my fault - now sorted and GET method appears to be working perfectly. Thanks for your help.

Rempty comments:

Don't forget "vote to award prize"

theflyingant comments:

Thanks, but this gives Undefined index: section_name error when I make a selection from the dropdown.

theflyingant comments:

Thanks, but this gives Undefined index: section_name error when I make a selection from the dropdown.

Andrea P comments:

oh I'm sorry, I haven't spotted another place where you should change POST to GET.

I've edited my first answer, let me know you it goes now

Andrea P comments:

ah!

and probably it's safer if the paginate_links will conditionally add the string only if a value has been set for the section_name


$big = 999999999; // need an unlikely integer
$paginate_links = paginate_links( array(
'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
'format' => '?paged=%#%',
'current' => $current_page,
'total' => $total_pages
) );

if ( $_GET['section_name'] ){
$paginate_links['add_args'] = array( 'section_name' => $_GET['section_name'] );
}
echo $paginate_links;


Andrea P comments:

no sorry, forget my previous comment! it's been a long day..

here is the correct one:


$big = 999999999; // need an unlikely integer
$paginate_links_args = array(
'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
'format' => '?paged=%#%',
'current' => $current_page,
'total' => $total_pages
);

if ( $_GET['section_name'] ){
$paginate_links_args[]['add_args'] = array( 'section_name'=>$_GET['section_name'] );
}

echo paginate_links($paginate_links_args);


Andrea P comments:

you have to keep the rest of your navigation functions, so at the end it'll look like this:


function catalogue_nav() {

$total_pages = $GLOBALS['wp_query']->max_num_pages;

if ($total_pages > 1){

$current_page = max(1, get_query_var('paged'));
echo '<nav class="pagination">';

$big = 999999999; // need an unlikely integer
$paginate_links_args = array(
'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
'format' => '?paged=%#%',
'current' => $current_page,
'total' => $total_pages
);

if ( $_GET['section_name'] ){
$paginate_links_args[]['add_args'] = array( 'section_name'=>$_GET['section_name'] );
}

echo paginate_links($paginate_links_args);

echo '</nav>';
}

}


Andrea P comments:

sorry.. typo:
this

$paginate_links_args[]['add_args'] = array( 'section_name'=>$_GET['section_name'] );


should be this:

$paginate_links_args['add_args'] = array( 'section_name'=>$_GET['section_name'] );


I hate the fact that you cannot edit a reply in this website.. -_-

theflyingant comments:

Andrea,

Thanks for your suggestions - problem is since switching from $_POST to $_GET the $wpdb->get_results query is returning empty. The variable $dropdown_selection still contains the selected value though.

theflyingant comments:

Andrea, now sorted the issue. Your answers were helpful in solving it thanks a lot.

Andrea P comments:

Hi there!

that's weird.. especially if $dropdown_selection is actually populated correctly..

I fear I might have confused you with my suggestions (mixed with other people suggestions too..) and maybe you have missed to edit something, or you are mixmatching our suggestions?

edit: I just had a quick look at your replies to others, is all working fine now?