获取类以了解变量

I'm facing a problem, I want the class Page to know the Variable '$format'.

// class1.php
<?php

  include('./class2.php');
  echo $format->getTest(); // returns :-) (declared in class2.php)

  class Page {

    PUBLIC function getText() {
      return $format->getTest(); // returns Call to a member function getTest() on null
    }

  }

  $page = new Page;

?>
 // class2.php
<?php

  class Format {

    PUBLIC function getTest() {
      return ":-)";
    }

 }

 $format = new Format;

?>

Any suggestions/ideas?

EDIT:

I found a way: return $GLOBALS['format']->getTest(); But I dont like it, its so much to type. Any other way(s)?

Philip

Proper objective solution is to pass variable to constructor, setter or as argument to getText() method. Choose one you find most appropriate for your case.

Constructor

class Page
{
    private $format;

    public function __construct(Format $format)
    {
        $this->format = $format;
    }

    public function getText()
    {
        return $this->format->getTest();
    }

}

$page = new Page($format);
echo $page->getText();

Setter

class Page
{
    private $format;

    public function setFormat(Format $format)
    {
        $this->format = $format;
    }

    public function getText()
    {
        return $this->format->getTest();
    }

}

$page = new Page;
$page->setFormat($format);
echo $page->getText();

Argument

class Page
{

    public function getText(Format $format)
    {
        return $format->getTest();
    }

}

$page = new Page;
echo $page->getText($format);