Php Pagination class and display issue - php

Question

I have a php pagination class with code as follows:
<?php
class Pagination {
private $num_pages = 1;
private $start = 0;
private $display;
private $start_display;
function __construct ($query, $display=10) {
if (!empty($query)) {
$this->display = $display;
if (isset($_GET['display']) && is_numeric($_GET['display'])) $this->display = (int) $_GET['display'];
if (isset($_GET['np']) && is_numeric($_GET['np']) && $_GET['np'] > 0) {
$this->num_pages = (int) $_GET['np'];
} else {
if (is_numeric($query)) {
$num_records = $query;
} else {
$result = db_query ($query);
if ($result->num_rows > 1 || strstr($query, 'COUNT') === false) {
$num_records = $result->num_rows;
} else {
$row = $result->fetch_row();
$num_records = $row[0];
}
}
if ($num_records > $this->display) $this->num_pages = ceil ($num_records/$this->display);
}
if (isset($_GET['s']) && is_numeric($_GET['s']) && $_GET['s'] > 0) $this->start = (int) $_GET['s'];
$this->start_display = " LIMIT {$this->start}, {$this->display}";
}
}
public function display ($split=5) {
global $page;
$html = '';
if ($this->num_pages <= 1) return $html;
//$page->link('pagination.css');
$url = $page->url ('add', '', 'np', $this->num_pages);
$current_page = ($this->start/$this->display) + 1;
$begin = $current_page - $split;
$end = $current_page + $split;
if ($begin < 1) {
$begin = 1;
$end = $split * 2;
}
if ($end > $this->num_pages) {
$end = $this->num_pages;
$begin = $end - ($split * 2);
$begin++; // add one so that we get double the split at the end
if ($begin < 1) $begin = 1;
}
if ($current_page != 1) {
$html .= '<a class="first" title="First" href="' . $page->url('add', $url, 's', 0) . '">«</a>';
$html .= '<a class="prev" title="Previous" href="' . $page->url('add', $url, 's', $this->start - $this->display) . '">Previous</a>';
} else {
$html .= '<span class="disabled first" title="First">«</span>';
$html .= '<span class="disabled prev" title="Previous">Previous</span>';
}
for ($i=$begin; $i<=$end; $i++) {
if ($i != $current_page) {
$html .= '<a title="' . $i . '" href="' . $page->url('add', $url, 's', ($this->display * ($i - 1))) . '">' . $i . '</a>';
} else {
$html .= '<span class="current">' . $i . '</span>';
}
}
if ($current_page != $this->num_pages) {
$html .= '<a class="next" title="Next" href="' . $page->url('add', $url, 's', $this->start + $this->display) . '">Next</a>';
$last = ($this->num_pages * $this->display) - $this->display;
$html .= '<a class="last" title="Last" href="' . $page->url('add', $url, 's', $last) . '">»</a>';
} else {
$html .= '<span class="disabled next" title="Next">Next</span>';
$html .= '<span class="disabled last" title="Last">»</span>';
}
return '<div class="pagination">' . $html . '</div>';
}
public function limit () {
return $this->start_display;
}
}
?>
I am calling the class as follows:
$page->link('pagination.css');
$links = new Pagination ($numrows);
I have a mysql query with LIMIT as $links->limit() and it is displaying 10 records correctly.
I am calling pagination display as:
$html .= $links->display();
But no pagination is displayed and I am getting the following error:
PHP Notice: Undefined variable: page in ......
and
Call to a member function link() on a non-object on line
$page->link('pagination.css');
I have the pagination.css file uploaded in the same folder too....
What is wrong with my code ?? Why am i getting the Notice that php is undefined variable though having a global scope in the class method? And Call to a member function link() on a non-object ??
Thanks in advance.
Note: Got the pagination Class from the following link:
Pagination Class Source

Answer 1

You have created an Class Definition, but never created an Instance of this Class Definition.
you have to instantiate class ?$page? in PHP to get an Instance in form of an object of it. For your example code you have to hold (save) this object instance in an variable with name "page" which was previously defined with global keyword.
$html = "";
global $page;
$page->link('pagination.css');
$links = new Pagination ($numrows);
$html .= $page->display();
var_dump($html);
HTH
Tobias