WP_Widget::update_callback( int $deprecated = 1 )

411	public function update_callback( $deprecated = 1 ) {412		global $wp_registered_widgets;413 414		$all_instances = $this->get_settings();415 416		// We need to update the data.417		if ( $this->updated ) {418			return;419		}420 421		if ( isset( $_POST['delete_widget'] ) && $_POST['delete_widget'] ) {422			// Delete the settings for this instance of the widget.423			if ( isset( $_POST['the-widget-id'] ) ) {424				$del_id = $_POST['the-widget-id'];425			} else {426				return;427			}428 429			if ( isset( $wp_registered_widgets[ $del_id ]['params'][0]['number'] ) ) {430				$number = $wp_registered_widgets[ $del_id ]['params'][0]['number'];431 432				if ( $this->id_base . '-' . $number === $del_id ) {433					unset( $all_instances[ $number ] );434				}435			}436		} else {437			if ( isset( $_POST[ 'widget-' . $this->id_base ] ) && is_array( $_POST[ 'widget-' . $this->id_base ] ) ) {438				$settings = $_POST[ 'widget-' . $this->id_base ];439			} elseif ( isset( $_POST['id_base'] ) && $_POST['id_base'] === $this->id_base ) {440				$num      = $_POST['multi_number'] ? (int) $_POST['multi_number'] : (int) $_POST['widget_number'];441				$settings = array( $num => array() );442			} else {443				return;444			}445 446			foreach ( $settings as $number => $new_instance ) {447				$new_instance = stripslashes_deep( $new_instance );448				$this->_set( $number );449 450				$old_instance = $all_instances[ $number ] ?? array();451 452				$was_cache_addition_suspended = wp_suspend_cache_addition();453				if ( $this->is_preview() && ! $was_cache_addition_suspended ) {454					wp_suspend_cache_addition( true );455				}456 457				$instance = $this->update( $new_instance, $old_instance );458 459				if ( $this->is_preview() ) {460					wp_suspend_cache_addition( $was_cache_addition_suspended );461				}462 463				/**464				 * Filters a widget's settings before saving.465				 *466				 * Returning false will effectively short-circuit the widget's ability467				 * to update settings.468				 *469				 * @since 2.8.0470				 *471				 * @param array     $instance     The current widget instance's settings.472				 * @param array     $new_instance Array of new widget settings.473				 * @param array     $old_instance Array of old widget settings.474				 * @param WP_Widget $widget       The current widget instance.475				 */476				$instance = apply_filters( 'widget_update_callback', $instance, $new_instance, $old_instance, $this );477 478				if ( false !== $instance ) {479					$all_instances[ $number ] = $instance;480				}481 482				break; // Run only once.483			}484		}485 486		$this->save_settings( $all_instances );487		$this->updated = true;488	}