Pagination issue with WP_List_table in WordPress - php

Question

I'm developing a plugin for WordPress. I use WP_List_Table which output rows from database nicely.
The issue I have is the pagination. If I have let's say 200 rows in the database and I set it to only display 50 rows per page, this works and I do get 1 of 4 pages.
On page 1 It displays ID 1 to ID 50. But when I click on page 2 it displays ID 2 to ID 51. So it only jumps 1 row and not 50. Where's the issue?
This will handle the data:
function prepare_items() {
global $wpdb;
/* Select project for user */
$table_name2 = $wpdb->prefix . 'project_name';
$current_user = wp_get_current_user();
$sql2 = "SELECT * FROM " . $wpdb->prefix . "project_name WHERE alloweduser = " . $current_user->ID;
$results2 = $wpdb->get_results($sql2) or die(mysql_error());
foreach( $results2 as $result2 ) {
$table_name = $wpdb->prefix . "project_name_" . $result2->projectname;
/* Define how many rows to show per page */
$per_page = 50;
$columns = $this->get_columns();
$hidden = array();
$sortable = $this->get_sortable_columns();
// here we configure table headers, defined in our methods
$this->_column_headers = array($columns, $hidden, $sortable);
// [OPTIONAL] process bulk action if any
$this->process_bulk_action();
// will be used in pagination settings
$total_items = $wpdb->get_var("SELECT COUNT(cid) FROM $table_name");
// prepare query params, as usual current page, order by and order direction
$paged = isset($_REQUEST['paged']) ? max(0, intval($_REQUEST['paged']) - 0) : 0;
$orderby = (isset($_REQUEST['orderby']) && in_array($_REQUEST['orderby'], array_keys($this->get_sortable_columns()))) ? $_REQUEST['orderby'] : 'cid';
$order = (isset($_REQUEST['order']) && in_array($_REQUEST['order'], array('ASC', 'DESC'))) ? $_REQUEST['order'] : 'ASC';
// Define $items array
// notice that last argument is ARRAY_A, so we will retrieve array
$this->items = $wpdb->get_results($wpdb->prepare("SELECT * FROM $table_name ORDER BY $orderby $order LIMIT %d OFFSET %d", $per_page, $paged), ARRAY_A);
// configure pagination
$this->set_pagination_args(array(
'total_items' => $total_items, // total items defined above
'per_page' => $per_page, // per page constant defined at top of method
'total_pages' => ceil($total_items / $per_page) // calculate pages count
));
}
}
}
This will output the data:
function custom_table_example_submissions_page_handler() {
global $wpdb;
$table = new Custom_Table_Example_List_Table();
$table->prepare_items();
$message = '';
if ('delete' === $table->current_action()) {
$message = '<div class="updated below-h2" id="message"><p>' . sprintf(__('Deleted %d submission(s).', 'custom_table_example'), count($_REQUEST['id'])) . '</p></div>';
}
?>
<div class="wrap">
<div class="icon32 icon32-posts-post" id="icon-edit">
<br></div>
<h2><?php _e('Submissions', 'custom_table_example')?>
</h2>
<?php echo $message; ?>
<form id="submissions-table" method="GET">
<input type="hidden" name="page" value="<?php echo $_REQUEST['page']; ?>"/>
<?php //$table->display(array('contributorname', 'email')); ?>
<?php $table->display(); ?>
</form>
</div>
<?php
}
Update:
get_columns:
function get_columns() {
$columns = array(
'cb' => '<input type="checkbox" />', //Render a checkbox instead of text
'name' => __('Name', 'custom_table_example'),
'upload' => __('Upload', 'custom_table_example'),
'upload2' => __('Upload', 'custom_table_example'),
'upload3' => __('Upload', 'custom_table_example'),
'upload4' => __('Upload', 'custom_table_example'),
'rate' => __('Rate', 'custom_table_example'),
);
return $columns;
}
$this->items is retrieved from:
https://core.trac.wordpress.org/browser/tags/4.0.1/src//wp-admin/includes/class-wp-list-table.php#L0
It's called with:
if (!class_exists('WP_List_Table')) {
require_once(ABSPATH . 'wp-admin/includes/class-wp-list-table.php');
}

Answer 1

I managed to solve it and answer my own question.
The issue was here:
$paged = isset($_REQUEST['paged']) ? max(0, intval($_REQUEST['paged']) - 0) : 0;
Since I want to output 50 rows per page I simply added -1 to $_REQUEST['paged'] and added * 50 which means that on page 1 row 1-50 is displayed and on page 2 rows 51-100 is displayed since 2*50 is 100 and so on.
Correct solutions is this:
$paged = isset($_REQUEST['paged']) ? max(0, intval($_REQUEST['paged'] -1) * 50) : 0;

Answer 2

I have same issue in my project so solution is here
$per_page = 5;
$columns = $this->get_columns();
$hidden = array();
$sortable = $this->get_sortable_columns();
$this->_column_headers = array($columns, $hidden, $sortable);
$this->process_bulk_action();
$paged = isset($_REQUEST['paged']) ? max(0, intval($_REQUEST['paged'] -1) * $per_page) : 0;
I hope Now your problem will be solve

Answer 3

$found_data = array_slice($this->table_data(),(($current_page-1)*$per_page),$per_page);
$this->items = $found_data;
Use above mention code in your prepare_items(). It devides your list of data into the chunks.