OOP, Shortcode Function and Property Types

Hi,

I’m struggling the PHP OOP concepts, trying to make a shortcode plugin.
Here’s my very simple shortcode class, so far:

class ell_jt_shortcode {
	static $defs = NULL;
	static $addscripts = false;

	function __construct() {
		///////////////////
		// Add shortcode //
		///////////////////
		add_shortcode( 'ell-jtweets', array( __CLASS__, 'handle_shortcode' ) );
	}
	function handle_shortcode( $atts ) {
		return var_dump(self::$addscripts);
	}
}
$jtshortcode = new ell_jt_shortcode();

This seems to work OK, but I’m wondering why I only seem to be able to access static variables inside the shortcode functions. From reading OOP tutorials, I was assuming that I could use a private or protected variable for $addscript, like so:

class ell_jt_shortcode {
	static $defs = NULL;
	private $addscripts = false;

	function __construct() {
		///////////////////
		// Add shortcode //
		///////////////////
		add_shortcode( 'ell-jtweets', array( __CLASS__, 'handle_shortcode' ) );
	}
	function handle_shortcode( $atts ) {
		return var_dump($this->addscripts);
	}
}
$jtshortcode = new ell_jt_shortcode();

But this produces a fatal “Using $this when not in object context in PHP” error. Is this as expected? Is there some other way I should go about creating a PHP class for my shortcode. Is using a static variable in this context OK? I’m using a static for the default settings, but I think this is OK, as they’re always going to be the same.

I’m still struggling with basic OOP concepts, I must admit. I’ve been writing procedural PHP for quite a long time, but am trying update myself, finally. It’s quite hard though, as a completely self-taught code-tinkerer.

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