Always show Previous & Next links using CodeIgniter Pagination Class

Question

Problem Description
When I'm at the first page, the previous link is not showing up and so do the next link when I'm at the last page. I set $config['prev_link']='previous' and $config['next_link']='next'.

Question
How to always present, using the CodeIgniter pagination class, the Previous and Next links as <p> tags when they are not in used?

Update
End up Solving it myself. See solution below. Working on v2.1.3

Answer 1

Here is the Solution:

1. Extend Codeigniter pagination class by creating a new file: MY_Pagination.php and placing it in the application/library folder.

2. Change all variables and classes prefix declarations from protected to public.

3. Define two public variable in MY_Pagination.php: $display_prev_link and $display_next_link and set it to FALSE.

4. In the create_links() function, add to the end of the if ($this->prev_link !== FALSE && $this->cur_page !== 1) statement an elseif statement:

   elseif ($this->display_prev_link && $this->cur_page === 1)
       $output .= $this->prev_tag_open.'<span>'.$this->prev_link.'</span>'.$this->next_tag_close;
   

   and another elseif statement to the end of the if ($this->next_link !== FALSE && $this->cur_page < $num_pages) statement:

   elseif ($this->display_next_link && $this->cur_page >= $num_pages)
       $output .= $this->next_tag_open.'<span>'.$this->next_link.'</span>'.$this->next_tag_close;
   

So Now,

By defining $config['display_prev_link'] and $config['display_prev_link'] equal to TRUE or FALSE, you can control the presentation of the Previous and Next links.

Here is the complete application/library/MY_Pagination.php file:

<?php  

// Extends the Pagination Class
// Add an option of presenting the PREVIOUS and NEXT links when they're not needed.
// by setting $display_prev_link - and - $display_next_link to true

// !!! EDITIONS => LINES 263 AND 316 !!!

defined('BASEPATH') OR exit('No direct script access allowed');

class MY_Pagination extends CI_Pagination {

    public $display_prev_link = false;
    public $display_next_link = false;

    public $base_url        = '';
    public $prefix      = '';
    public $suffix      = '';
    public $total_rows      = 0;
    public $per_page        = 10;
    public $num_links       = 2;
    public $cur_page        = 0;
    public $use_page_numbers    = FALSE;
    public $first_link      = '&lsaquo; First';
    public $next_link       = '&gt;';
    public $prev_link       = '&lt;';
    public $last_link       = 'Last &rsaquo;';
    public $uri_segment     = 3;
    public $full_tag_open   = '';
    public $full_tag_close  = '';
    public $first_tag_open  = '';
    public $first_tag_close = '';
    public $last_tag_open   = '';
    public $last_tag_close  = '';
    public $first_url       = '';
    public $cur_tag_open        = '<strong>';
    public $cur_tag_close   = '</strong>';
    public $next_tag_open   = '';
    public $next_tag_close  = '';
    public $prev_tag_open   = '';
    public $prev_tag_close  = '';
    public $num_tag_open        = '';
    public $num_tag_close   = '';
    public $page_query_string   = FALSE;
    public $query_string_segment = 'per_page';
    public $display_pages   = TRUE;
    public $_attributes     = '';
    public $_link_types     = array();
    public $reuse_query_string   = FALSE;
    public $data_page_attr  = 'data-ci-pagination-page';

    // --------------------------------------------------------------------

    /**
     * Constructor
     *
     * @param   array   $params Initialization parameters
     * @return  void
     */
    public function __construct($params = array())
    {
        $this->initialize($params);
        log_message('debug', 'Pagination Class Initialized');
    }

    // --------------------------------------------------------------------

    /**
     * Initialize Preferences
     *
     * @param   array   $params Initialization parameters
     * @return  void
     */
    public function initialize($params = array())
    {
        $attributes = array();

        if (isset($params['attributes']) && is_array($params['attributes']))
        {
            $attributes = $params['attributes'];
            unset($params['attributes']);
        }

        // Deprecated legacy support for the anchor_class option
        // Should be removed in CI 3.1+
        if (isset($params['anchor_class']))
        {
            empty($params['anchor_class']) OR $attributes['class'] = $params['anchor_class'];
            unset($params['anchor_class']);
        }

        $this->_parse_attributes($attributes);

        if (count($params) > 0)
        {
            foreach ($params as $key => $val)
            {
                if (isset($this->$key))
                {
                    $this->$key = $val;
                }
            }
        }
    }

    // --------------------------------------------------------------------

    /**
     * Generate the pagination links
     *
     * @return  string
     */
    public function create_links()
    {
        // If our item count or per-page total is zero there is no need to continue.
        if ($this->total_rows === 0 OR $this->per_page === 0)
        {
            return '';
        }

        // Calculate the total number of pages
        $num_pages = (int) ceil($this->total_rows / $this->per_page);

        // Is there only one page? Hm... nothing more to do here then.
        if ($num_pages === 1)
        {
            //$uri_page_number = 1;
            //return '';
        }

        // Set the base page index for starting page number
        $base_page = ($this->use_page_numbers) ? 1 : 0;

        // Determine the current page number.
        $CI =& get_instance();

        // See if we are using a prefix or suffix on links
        if ($this->prefix !== '' OR $this->suffix !== '')
        {
            $this->cur_page = (int) str_replace(array($this->prefix, $this->suffix), '', $CI->uri->rsegment($this->uri_segment));
        }

        if ($CI->config->item('enable_query_strings') === TRUE OR $this->page_query_string === TRUE)
        {
            if ($CI->input->get($this->query_string_segment) != $base_page)
            {
                $this->cur_page = (int) $CI->input->get($this->query_string_segment);
            }
        }
        elseif ( ! $this->cur_page && $CI->uri->segment($this->uri_segment) !== $base_page)
        {
            $this->cur_page = (int) $CI->uri->rsegment($this->uri_segment);
        }

        // Set current page to 1 if it's not valid or if using page numbers instead of offset
        if ( ! is_numeric($this->cur_page) OR ($this->use_page_numbers && $this->cur_page === 0))
        {
            $this->cur_page = $base_page;
        }

        $this->num_links = (int) $this->num_links;

        if ($this->num_links < 1)
        {
            show_error('Your number of links must be a positive number.');
        }

        // Is the page number beyond the result range?
        // If so we show the last page
        if ($this->use_page_numbers)
        {
            if ($this->cur_page > $num_pages)
            {
                $this->cur_page = $num_pages;
            }
        }
        elseif ($this->cur_page > $this->total_rows)
        {
            $this->cur_page = ($num_pages - 1) * $this->per_page;
        }

        $uri_page_number = $this->cur_page;

        if ( ! $this->use_page_numbers)
        {
            $this->cur_page = (int) floor(($this->cur_page/$this->per_page) + 1);
        }

        // Calculate the start and end numbers. These determine
        // which number to start and end the digit links with
        $start  = (($this->cur_page - $this->num_links) > 0) ? $this->cur_page - ($this->num_links - 1) : 1;
        $end    = (($this->cur_page + $this->num_links) < $num_pages) ? $this->cur_page + $this->num_links : $num_pages;

        // Is pagination being used over GET or POST? If get, add a per_page query
        // string. If post, add a trailing slash to the base URL if needed
        if ($CI->config->item('enable_query_strings') === TRUE OR $this->page_query_string === TRUE)
        {
            $segment = (strpos($this->base_url, '?')) ? '&amp;' : '?';
            $this->base_url = rtrim($this->base_url).$segment.$this->query_string_segment.'=';
        }
        else
        {
            $this->base_url = rtrim($this->base_url, '/') .'/';
        }

        // And here we go...
        $output = '';
        $query_string = '';

        // Add anything in the query string back to the links
        // Note: Nothing to do with query_string_segment or any other query string options
        if ($this->reuse_query_string === TRUE)
        {
            $get = $CI->input->get();

            // Unset the controll, method, old-school routing options
            unset($get['c'], $get['m'], $get[$this->query_string_segment]);

            if ( ! empty($get))
            {
                // Put everything else onto the end
                $query_string = (strpos($this->base_url, '?') !== FALSE ? '&amp;' : '?')
                        .http_build_query($get, '', '&amp;');

                // Add this after the suffix to put it into more links easily
                $this->suffix .= $query_string;
            }
        }

        // Render the "First" link
        if ($this->first_link !== FALSE && $this->cur_page > ($this->num_links + 1))
        {
            $first_url = ($this->first_url === '') ? $this->base_url : $this->first_url;

            // Take the general parameters, and squeeze this pagination-page attr in there for JS fw's
            $attributes = sprintf('%s %s="%d"', $this->_attributes, $this->data_page_attr, 1);

            $output .= $this->first_tag_open.'<a href="'.$first_url.'"'.$attributes.$this->_attr_rel('start').'>'
                .$this->first_link.'</a>'.$this->first_tag_close;
        }

        // Render the "previous" link
        if ($this->prev_link !== FALSE && $this->cur_page !== 1)
        {
            $i = ($this->use_page_numbers) ? $uri_page_number - 1 : $uri_page_number - $this->per_page;

            // Take the general parameters, and squeeze this pagination-page attr in there for JS fw's
            $attributes = sprintf('%s %s="%d"', $this->_attributes, $this->data_page_attr, (int) $i);

            if ($i === $base_page && $this->first_url !== '')
            {
                $output .= $this->prev_tag_open.'<a href="'.$this->first_url.$query_string.'"'.$attributes.$this->_attr_rel('prev').'>'
                    .$this->prev_link.'</a>'.$this->prev_tag_close;
            }
            else
            {
                $append = ($i === $base_page) ? $query_string : $this->prefix.$i.$this->suffix;
                $output .= $this->prev_tag_open.'<a href="'.$this->base_url.$append.'"'.$attributes.$this->_attr_rel('prev').'>'
                    .$this->prev_link.'</a>'.$this->prev_tag_close;
            }

        } 
// !!!!!!!! START EDITION !!!!!!!!!!
        elseif ($this->display_prev_link && $this->cur_page === 1) {
                $output .= $this->prev_tag_open.'<span>'.$this->prev_link.'</span>'.$this->next_tag_close;
            }
// !!!!!!!! END EDITION !!!!!!!!!!

        // Render the pages
        if ($this->display_pages !== FALSE)
        {
            // Write the digit links
            for ($loop = $start -1; $loop <= $end; $loop++)
            {
                $i = ($this->use_page_numbers) ? $loop : ($loop * $this->per_page) - $this->per_page;

                // Take the general parameters, and squeeze this pagination-page attr in there for JS fw's
                $attributes = sprintf('%s %s="%d"', $this->_attributes, $this->data_page_attr, (int) $i);

                if ($i >= $base_page)
                {
                    if ($this->cur_page === $loop)
                    {
                        $output .= $this->cur_tag_open.$loop.$this->cur_tag_close; // Current page
                    }
                    else
                    {
                        $n = ($i === $base_page) ? '' : $i;
                        if ($n === '' && ! empty($this->first_url))
                        {
                            //$output .= $this->num_tag_open.'<a href="'.$this->first_url.$query_string.'"'.$attributes.$this->_attr_rel('start').'>'
                            //  .$loop.'</a>'.$this->num_tag_close;
                        }
                        else
                        {
                            $append = ($n === '') ? $query_string : $this->prefix.$n.$this->suffix;
                            $output .= $this->num_tag_open.'<a href="'.$this->base_url.$append.'"'.$attributes.$this->_attr_rel('start').'>'
                                .$loop.'</a>'.$this->num_tag_close;
                        }
                    }
                }
            }
        }

        // Render the "next" link
        if ($this->next_link !== FALSE && $this->cur_page < $num_pages)
        {
            $i = ($this->use_page_numbers) ? $this->cur_page + 1 : $this->cur_page * $this->per_page;

            // Take the general parameters, and squeeze this pagination-page attr in there for JS fw's
            $attributes = sprintf('%s %s="%d"', $this->_attributes, $this->data_page_attr, (int) $i);

            $output .= $this->next_tag_open.'<a href="'.$this->base_url.$this->prefix.$i.$this->suffix.'"'.$attributes
                .$this->_attr_rel('next').'>'.$this->next_link.'</a>'.$this->next_tag_close;
        } 
// !!!!!!!! START EDITION !!!!!!!!!!
        elseif ($this->display_next_link && $this->cur_page >= $num_pages) {
            $output .= $this->next_tag_open.'<span>'.$this->next_link.'</span>'.$this->next_tag_close;
        }
// !!!!!!!! END EDITION !!!!!!!!!!

        // Render the "Last" link
        if ($this->last_link !== FALSE && ($this->cur_page + $this->num_links) < $num_pages)
        {
            $i = ($this->use_page_numbers) ? $num_pages : ($num_pages * $this->per_page) - $this->per_page;

            // Take the general parameters, and squeeze this pagination-page attr in there for JS fw's
            $attributes = sprintf('%s %s="%d"', $this->_attributes, $this->data_page_attr, (int) $i);

            $output .= $this->last_tag_open.'<a href="'.$this->base_url.$this->prefix.$i.$this->suffix.'"'.$attributes.'>'
                .$this->last_link.'</a>'.$this->last_tag_close;
        }

        // Kill double slashes. Note: Sometimes we can end up with a double slash
        // in the penultimate link so we'll kill all double slashes.
        $output = preg_replace('#([^:])//+#', '\\1/', $output);

        // Add the wrapper HTML if exists
        return $this->full_tag_open.$output.$this->full_tag_close;
    }

    // --------------------------------------------------------------------

    /**
     * Parse attributes
     *
     * @param   array   $attributes
     * @return  void
     */
    public function _parse_attributes($attributes)
    {
        isset($attributes['rel']) OR $attributes['rel'] = TRUE;
        $this->_link_types = ($attributes['rel'])
                    ? array('start' => 'start', 'prev' => 'prev', 'next' => 'next')
                    : array();
        unset($attributes['rel']);

        $this->_attributes = '';
        foreach ($attributes as $key => $value)
        {
            $this->_attributes .= ' '.$key.'="'.$value.'"';
        }
    }

    // --------------------------------------------------------------------

    /**
     * Add "rel" attribute
     *
     * @link    http://www.w3.org/TR/html5/links.html#linkTypes
     * @param   string  $type
     * @return  string
     */
    public function _attr_rel($type)
    {
        if (isset($this->_link_types[$type]))
        {
            unset($this->_link_types[$type]);
            return ' rel="'.$type.'"';
        }

        return '';
    }

}

/* End of file Pagination.php */
/* Location: ./system/libraries/Pagination.php */

And don't forget to set $config['$display_prev_link'] and $config['$display_next_link'] set to true or false according to your needs.

Good Luck!