$_POST[ 'widget-' . $this->id_base ] ) && is_array( $_POST[ 'widget-' . $this->id_base ] ) ) {
				$settings = $_POST[ 'widget-' . $this->id_base ];
			} elseif ( isset( $_POST['id_base'] ) && $_POST['id_base'] === $this->id_base ) {
				$num      = $_POST['multi_number'] ? (int) $_POST['multi_number'] : (int) $_POST['widget_number'];
				$settings = array( $num => array() );
			} else {
				return;
			}

			foreach ( $settings as $number => $new_instance ) {
				$new_instance = stripslashes_deep( $new_instance );
				$this->_set( $number );

				$old_instance = isset( $all_instances[ $number ] ) ? $all_instances[ $number ] : array();

				$was_cache_addition_suspended = wp_suspend_cache_addition();
				if ( $this->is_preview() && ! $was_cache_addition_suspended ) {
					wp_suspend_cache_addition( true );
				}

				$instance = $this->update( $new_instance, $old_instance );

				if ( $this->is_preview() ) {
					wp_suspend_cache_addition( $was_cache_addition_suspended );
				}

				/**
				 * Filters a widget's settings before saving.
				 *
				 * Returning false will effectively short-circuit the widget's ability
				 * to update settings.
				 *
				 * @since 2.8.0
				 *
				 * @param array     $instance     The current widget instance's settings.
				 * @param array     $new_instance Array of new widget settings.
				 * @param array     $old_instance Array of old widget settings.
				 * @param WP_Widget $widget       The current widget instance.
				 */
				$instance = apply_filters( 'widget_update_callback', $instance, $new_instance, $old_instance, $this );

				if ( false !== $instance ) {
					$all_instances[ $number ] = $instance;
				}

				break; // Run only once.
			}
		}

		$this->save_settings( $all_instances );
		$this->updated = true;
	}

	/**
	 * Generates the widget control form (Do NOT override).
	 *
	 * @since 2.8.0
	 *
	 * @param int|array $widget_args {
	 *     Optional. Internal order number of the widget instance, or array of multi-widget arguments.
	 *     Default 1.
	 *
	 *     @type int $number Number increment used for multiples of the same widget.
	 * }
	 * @return string|null
	 */
	public function form_callback( $widget_args = 1 ) {
		if ( is_numeric( $widget_args ) ) {
			$widget_args = array( 'number' => $widget_args );
		}

		$widget_args   = wp_parse_args( $widget_args, array( 'number' => -1 ) );
		$all_instances = $this->get_settings();

		if ( -1 === $widget_args['number'] ) {
			// We echo out a form where 'number' can be set later.
			$this->_set( '__i__' );
			$instance = array();
		} else {
			$this->_set( $widget_args['number'] );
			$instance = $all_instances[ $widget_args['number'] ];
		}

		/**
		 * Filters the widget instance's settings before displaying the control form.
		 *
		 * Returning false effectively short-circuits display of the control form.
		 *
		 * @since 2.8.0
		 *
		 * @param array     $instance The current widget instance's settings.
		 * @param WP_Widget $widget   The current widget instance.
		 */
		$instance = apply_filters( 'widget_form_callback', $instance, $this );

		$return = null;

		if ( false !== $instance ) {
			$return = $this->form( $instance );

			/**
			 * Fires at the end of the widget control form.
			 *
			 * Use this hook to add extra fields to the widget form. The hook
			 * is only fired if the value passed to the 'widget_form_callback'
			 * hook is not false.
			 *
			 * Note: If the widget has no form, the text echoed from the default
			 * form method can be hidden using CSS.
			 *
			 * @since 2.8.0
			 *
			 * @param WP_Widget $widget   The widget instance (passed by reference).
			 * @param null      $return   Return null if new fields are added.
			 * @param array     $instance An array of the widget's settings.
			 */
			do_action_ref_array( 'in_widget_form', array( &$this, &$return, $instance ) );
		}

		return $return;
	}

	/**
	 * Registers an instance of the widget class.
	 *
	 * @since 2.8.0
	 *
	 * @param int $number Optional. The unique order number of this widget instance
	 *                    compared to other instances of the same class. Default -1.
	 */
	public function _register_one( $number = -1 ) {
		wp_register_sidebar_widget(
			$this->id,
			$this->name,
			$this->_get_display_callback(),
			$this->widget_options,
			array( 'number' => $number )
		);

		_register_widget_update_callback(
			$this->id_base,
			$this->_get_update_callback(),
			$this->control_options,
			array( 'number' => -1 )
		);

		_register_widget_form_callback(
			$this->id,
			$this->name,
			$this->_get_form_callback(),
			$this->control_options,
			array( 'number' => $number )
		);
	}

	/**
	 * Saves the settings for all instances of the widget class.
	 *
	 * @since 2.8.0
	 *
	 * @param array $settings Multi-dimensional array of widget instance settings.
	 */
	public function save_settings( $settings ) {
		$settings['_multiwidget'] = 1;
		update_option( $this->option_name, $settings );
	}

	/**
	 * Retrieves the settings for all instances of the widget class.
	 *
	 * @since 2.8.0
	 *
	 * @return array Multi-dimensional array of widget instance settings.
	 */
	public function get_settings() {

		$settings = get_option( $this->option_name );

		if ( false === $settings ) {
			$settings = array();
			if ( isset( $this->alt_option_name ) ) {
				// Get settings from alternative (legacy) option.
				$settings = get_option( $this->alt_option_name, array() );

				// Delete the alternative (legacy) option as the new option will be created using `$this->option_name`.
				delete_option( $this->alt_option_name );
			}
			// Save an option so it can be autoloaded next time.
			$this->save_settings( $settings );
		}

		if ( ! is_array( $settings ) && ! ( $settings instanceof ArrayObject || $settings instanceof ArrayIterator ) ) {
			$settings = array();
		}

		if ( ! empty( $settings ) && ! isset( $settings['_multiwidget'] ) ) {
			// Old format, convert if single widget.
			$settings = wp_convert_widget_settings( $this->id_base, $this->option_name, $settings );
		}

		unset( $settings['_multiwidget'], $settings['__i__'] );

		return $settings;
	}
}