register dependency css and js inside a plugin class

You’re using the incorrect hook. The only hook is wp_enqueue_scripts (plural). You use wp_enqueue_style() and wp_register_script() etc. on that hook, but the hook is always the same.

So this:

add_action('wp_enqueue_script' , array( $this, 'initBootstrap' ));
add_action('wp_enqueue_style' , array( $this, 'initBootstrap' ));
add_action('wp_register_script' , array( $this, 'initParallax' ));
add_action('wp_register_style' , array( $this, 'initParallax' ));
add_action('wp_register_script' , array( $this, 'initSwiper' ));
add_action('wp_register_style' , array( $this, 'initSwiper' ));

Needs to be:

add_action('wp_enqueue_scripts' , array( $this, 'initBootstrap' ));
add_action('wp_enqueue_scripts' , array( $this, 'initBootstrap' ));
add_action('wp_enqueue_scripts' , array( $this, 'initParallax' ));
add_action('wp_enqueue_scripts' , array( $this, 'initParallax' ));
add_action('wp_enqueue_scripts' , array( $this, 'initSwiper' ));
add_action('wp_enqueue_scripts' , array( $this, 'initSwiper' ));

That’s the reason it wasn’t working, but you’re also misusing wp_script_is(). It won’t affect your code, since the result will always be false, but you need to pass the handle of the script, not the filename.

So this:

if( !wp_style_is( 'universal-parallax.min.css' , 'enqueued' ) ){
  wp_register_style( 'parallax' , plugin_dir_url(__FILE__).'/css/universal-parallax.min.css' );
}

Should be:

if( !wp_style_is( 'parallax', 'enqueued' ) ){
  wp_register_style( 'parallax' , plugin_dir_url(__FILE__).'/css/universal-parallax.min.css' );
}

However, you really don’t need that condition at all. If the script is already enqueued, then nothing’s going to happen, so there’s no reason to check for it.

Related Posts: