/**
  * Gets instance of class.
  *
  * @return WP_Google_DFP_Ads_Settings_Fields Instance of the class.
  */
 public static function get_instance()
 {
     if (null == self::$instance) {
         self::$instance = new self();
     }
     return self::$instance;
 }
 /**
  * Renders view.
  */
 public function __render()
 {
     $title = __('Google DFP Ads Settings', WP_Google_DFP_Ads::get_instance()->get_slug());
     echo '<h2>' . $title . '</h2>';
     echo '<form class="' . $this->id . '" method="post" action="options.php">';
     do_settings_sections($this->id);
     settings_fields(WP_Google_DFP_Ads_Settings_Fields::get_instance()->get_id());
     submit_button();
     echo '</form>';
 }
 /**
  * Initializes settings.
  */
 public function __initialize()
 {
     add_settings_field($this->id, __('Script Block', WP_Google_DFP_Ads::get_instance()->get_slug()), array($this, '__render'), WP_Google_DFP_Ads_Settings::get_instance()->get_id(), WP_Google_DFP_Ads_Settings_Head_Section::get_instance()->get_id());
     register_setting(WP_Google_DFP_Ads_Settings_Fields::get_instance()->get_id(), $this->id);
 }