Title: WP_Widget
Published: April 25, 2014
Last modified: April 28, 2025

---

# class WP_Widget {}

## In this article

 * [Description](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#description)
 * [Methods](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#methods)
 * [Source](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#source)
 * [Related](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#related)
 * [Changelog](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#changelog)
 * [User Contributed Notes](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#user-contributed-notes)

[ Back to top](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#wp--skip-link--target)

Core base class extended to register widgets.

## 󠀁[Description](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#description)󠁿

This class must be extended for each widget, and [WP_Widget::widget()](https://developer.wordpress.org/reference/classes/wp_widget/widget/)
must be overridden.

If adding widget options, [WP_Widget::update()](https://developer.wordpress.org/reference/classes/wp_widget/update/)
and [WP_Widget::form()](https://developer.wordpress.org/reference/classes/wp_widget/form/)
should also be overridden.

## 󠀁[Methods](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#methods)󠁿

| Name | Description | 
| [WP_Widget::__construct](https://developer.wordpress.org/reference/classes/wp_widget/__construct/) | PHP5 constructor. | 
| [WP_Widget::_get_display_callback](https://developer.wordpress.org/reference/classes/wp_widget/_get_display_callback/) | Retrieves the widget display callback. | 
| [WP_Widget::_get_form_callback](https://developer.wordpress.org/reference/classes/wp_widget/_get_form_callback/) | Retrieves the form callback. | 
| [WP_Widget::_get_update_callback](https://developer.wordpress.org/reference/classes/wp_widget/_get_update_callback/) | Retrieves the widget update callback. | 
| [WP_Widget::_register](https://developer.wordpress.org/reference/classes/wp_widget/_register/) | Register all widget instances of this widget class. | 
| [WP_Widget::_register_one](https://developer.wordpress.org/reference/classes/wp_widget/_register_one/) | Registers an instance of the widget class. | 
| [WP_Widget::_set](https://developer.wordpress.org/reference/classes/wp_widget/_set/) | Sets the internal order number for the widget instance. | 
| [WP_Widget::display_callback](https://developer.wordpress.org/reference/classes/wp_widget/display_callback/) | Generates the actual widget content (Do NOT override). | 
| [WP_Widget::form](https://developer.wordpress.org/reference/classes/wp_widget/form/) | Outputs the settings update form. | 
| [WP_Widget::form_callback](https://developer.wordpress.org/reference/classes/wp_widget/form_callback/) | Generates the widget control form (Do NOT override). | 
| [WP_Widget::get_field_id](https://developer.wordpress.org/reference/classes/wp_widget/get_field_id/) | Constructs id attributes for use in [WP_Widget::form()](https://developer.wordpress.org/reference/classes/wp_widget/form/) fields. | 
| [WP_Widget::get_field_name](https://developer.wordpress.org/reference/classes/wp_widget/get_field_name/) | Constructs name attributes for use in form() fields | 
| [WP_Widget::get_settings](https://developer.wordpress.org/reference/classes/wp_widget/get_settings/) | Retrieves the settings for all instances of the widget class. | 
| [WP_Widget::is_preview](https://developer.wordpress.org/reference/classes/wp_widget/is_preview/) | Determines whether the current request is inside the Customizer preview. | 
| [WP_Widget::save_settings](https://developer.wordpress.org/reference/classes/wp_widget/save_settings/) | Saves the settings for all instances of the widget class. | 
| [WP_Widget::update](https://developer.wordpress.org/reference/classes/wp_widget/update/) | Updates a particular instance of a widget. | 
| [WP_Widget::update_callback](https://developer.wordpress.org/reference/classes/wp_widget/update_callback/) | Handles changed settings (Do NOT override). | 
| [WP_Widget::widget](https://developer.wordpress.org/reference/classes/wp_widget/widget/) | Echoes the widget content. | 
| [WP_Widget::WP_Widget](https://developer.wordpress.org/reference/classes/wp_widget/wp_widget/) | PHP4 constructor. — deprecated |

## 󠀁[Source](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#source)󠁿

    ```php
    class WP_Widget {

    	/**
    	 * Root ID for all widgets of this type.
    	 *
    	 * @since 2.8.0
    	 * @var mixed|string
    	 */
    	public $id_base;

    	/**
    	 * Name for this widget type.
    	 *
    	 * @since 2.8.0
    	 * @var string
    	 */
    	public $name;

    	/**
    	 * Option name for this widget type.
    	 *
    	 * @since 2.8.0
    	 * @var string
    	 */
    	public $option_name;

    	/**
    	 * Alt option name for this widget type.
    	 *
    	 * @since 2.8.0
    	 * @var string
    	 */
    	public $alt_option_name;

    	/**
    	 * Option array passed to wp_register_sidebar_widget().
    	 *
    	 * @since 2.8.0
    	 * @var array
    	 */
    	public $widget_options;

    	/**
    	 * Option array passed to wp_register_widget_control().
    	 *
    	 * @since 2.8.0
    	 * @var array
    	 */
    	public $control_options;

    	/**
    	 * Unique ID number of the current instance.
    	 *
    	 * @since 2.8.0
    	 * @var bool|int
    	 */
    	public $number = false;

    	/**
    	 * Unique ID string of the current instance (id_base-number).
    	 *
    	 * @since 2.8.0
    	 * @var bool|string
    	 */
    	public $id = false;

    	/**
    	 * Whether the widget data has been updated.
    	 *
    	 * Set to true when the data is updated after a POST submit - ensures it does
    	 * not happen twice.
    	 *
    	 * @since 2.8.0
    	 * @var bool
    	 */
    	public $updated = false;

    	//
    	// Member functions that must be overridden by subclasses.
    	//

    	/**
    	 * Echoes the widget content.
    	 *
    	 * Subclasses should override this function to generate their widget code.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param array $args     Display arguments including 'before_title', 'after_title',
    	 *                        'before_widget', and 'after_widget'.
    	 * @param array $instance The settings for the particular instance of the widget.
    	 */
    	public function widget( $args, $instance ) {
    		die( 'function WP_Widget::widget() must be overridden in a subclass.' );
    	}

    	/**
    	 * Updates a particular instance of a widget.
    	 *
    	 * This function should check that `$new_instance` is set correctly. The newly-calculated
    	 * value of `$instance` should be returned. If false is returned, the instance won't be
    	 * saved/updated.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param array $new_instance New settings for this instance as input by the user via
    	 *                            WP_Widget::form().
    	 * @param array $old_instance Old settings for this instance.
    	 * @return array Settings to save or bool false to cancel saving.
    	 */
    	public function update( $new_instance, $old_instance ) {
    		return $new_instance;
    	}

    	/**
    	 * Outputs the settings update form.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param array $instance The settings for the particular instance of the widget.
    	 * @return string|void Default return is 'noform'.
    	 */
    	public function form( $instance ) {
    		echo '<p class="no-options-widget">' . __( 'There are no options for this widget.' ) . '</p>';
    		return 'noform';
    	}

    	// Functions you'll need to call.

    	/**
    	 * PHP5 constructor.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param string $id_base         Base ID for the widget, lowercase and unique. If left empty,
    	 *                                a portion of the widget's PHP class name will be used. Has to be unique.
    	 * @param string $name            Name for the widget displayed on the configuration page.
    	 * @param array  $widget_options  Optional. Widget options. See wp_register_sidebar_widget() for
    	 *                                information on accepted arguments. Default empty array.
    	 * @param array  $control_options Optional. Widget control options. See wp_register_widget_control() for
    	 *                                information on accepted arguments. Default empty array.
    	 */
    	public function __construct( $id_base, $name, $widget_options = array(), $control_options = array() ) {
    		if ( ! empty( $id_base ) ) {
    			$id_base = strtolower( $id_base );
    		} else {
    			$id_base = preg_replace( '/(wp_)?widget_/', '', strtolower( get_class( $this ) ) );
    		}

    		$this->id_base         = $id_base;
    		$this->name            = $name;
    		$this->option_name     = 'widget_' . $this->id_base;
    		$this->widget_options  = wp_parse_args(
    			$widget_options,
    			array(
    				'classname'                   => str_replace( '\\', '_', $this->option_name ),
    				'customize_selective_refresh' => false,
    			)
    		);
    		$this->control_options = wp_parse_args( $control_options, array( 'id_base' => $this->id_base ) );
    	}

    	/**
    	 * PHP4 constructor.
    	 *
    	 * @since 2.8.0
    	 * @deprecated 4.3.0 Use __construct() instead.
    	 *
    	 * @see WP_Widget::__construct()
    	 *
    	 * @param string $id_base         Base ID for the widget, lowercase and unique. If left empty,
    	 *                                a portion of the widget's PHP class name will be used. Has to be unique.
    	 * @param string $name            Name for the widget displayed on the configuration page.
    	 * @param array  $widget_options  Optional. Widget options. See wp_register_sidebar_widget() for
    	 *                                information on accepted arguments. Default empty array.
    	 * @param array  $control_options Optional. Widget control options. See wp_register_widget_control() for
    	 *                                information on accepted arguments. Default empty array.
    	 */
    	public function WP_Widget( $id_base, $name, $widget_options = array(), $control_options = array() ) {
    		_deprecated_constructor( 'WP_Widget', '4.3.0', get_class( $this ) );
    		WP_Widget::__construct( $id_base, $name, $widget_options, $control_options );
    	}

    	/**
    	 * Constructs name attributes for use in form() fields
    	 *
    	 * This function should be used in form() methods to create name attributes for fields
    	 * to be saved by update()
    	 *
    	 * @since 2.8.0
    	 * @since 4.4.0 Array format field names are now accepted.
    	 *
    	 * @param string $field_name Field name.
    	 * @return string Name attribute for `$field_name`.
    	 */
    	public function get_field_name( $field_name ) {
    		$pos = strpos( $field_name, '[' );

    		if ( false !== $pos ) {
    			// Replace the first occurrence of '[' with ']['.
    			$field_name = '[' . substr_replace( $field_name, '][', $pos, strlen( '[' ) );
    		} else {
    			$field_name = '[' . $field_name . ']';
    		}

    		return 'widget-' . $this->id_base . '[' . $this->number . ']' . $field_name;
    	}

    	/**
    	 * Constructs id attributes for use in WP_Widget::form() fields.
    	 *
    	 * This function should be used in form() methods to create id attributes
    	 * for fields to be saved by WP_Widget::update().
    	 *
    	 * @since 2.8.0
    	 * @since 4.4.0 Array format field IDs are now accepted.
    	 *
    	 * @param string $field_name Field name.
    	 * @return string ID attribute for `$field_name`.
    	 */
    	public function get_field_id( $field_name ) {
    		$field_name = str_replace( array( '[]', '[', ']' ), array( '', '-', '' ), $field_name );
    		$field_name = trim( $field_name, '-' );

    		return 'widget-' . $this->id_base . '-' . $this->number . '-' . $field_name;
    	}

    	/**
    	 * Register all widget instances of this widget class.
    	 *
    	 * @since 2.8.0
    	 */
    	public function _register() {
    		$settings = $this->get_settings();
    		$empty    = true;

    		// When $settings is an array-like object, get an intrinsic array for use with array_keys().
    		if ( $settings instanceof ArrayObject || $settings instanceof ArrayIterator ) {
    			$settings = $settings->getArrayCopy();
    		}

    		if ( is_array( $settings ) ) {
    			foreach ( array_keys( $settings ) as $number ) {
    				if ( is_numeric( $number ) ) {
    					$this->_set( $number );
    					$this->_register_one( $number );
    					$empty = false;
    				}
    			}
    		}

    		if ( $empty ) {
    			// If there are none, we register the widget's existence with a generic template.
    			$this->_set( 1 );
    			$this->_register_one();
    		}
    	}

    	/**
    	 * Sets the internal order number for the widget instance.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param int $number The unique order number of this widget instance compared to other
    	 *                    instances of the same class.
    	 */
    	public function _set( $number ) {
    		$this->number = $number;
    		$this->id     = $this->id_base . '-' . $number;
    	}

    	/**
    	 * Retrieves the widget display callback.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @return callable Display callback.
    	 */
    	public function _get_display_callback() {
    		return array( $this, 'display_callback' );
    	}

    	/**
    	 * Retrieves the widget update callback.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @return callable Update callback.
    	 */
    	public function _get_update_callback() {
    		return array( $this, 'update_callback' );
    	}

    	/**
    	 * Retrieves the form callback.
    	 *
    	 * @since 2.8.0
    	 *
    	 * @return callable Form callback.
    	 */
    	public function _get_form_callback() {
    		return array( $this, 'form_callback' );
    	}

    	/**
    	 * Determines whether the current request is inside the Customizer preview.
    	 *
    	 * If true -- the current request is inside the Customizer preview, then
    	 * the object cache gets suspended and widgets should check this to decide
    	 * whether they should store anything persistently to the object cache,
    	 * to transients, or anywhere else.
    	 *
    	 * @since 3.9.0
    	 *
    	 * @global WP_Customize_Manager $wp_customize
    	 *
    	 * @return bool True if within the Customizer preview, false if not.
    	 */
    	public function is_preview() {
    		global $wp_customize;
    		return ( isset( $wp_customize ) && $wp_customize->is_preview() );
    	}

    	/**
    	 * Generates the actual widget content (Do NOT override).
    	 *
    	 * Finds the instance and calls WP_Widget::widget().
    	 *
    	 * @since 2.8.0
    	 *
    	 * @param array     $args        Display arguments. See WP_Widget::widget() for information
    	 *                               on accepted arguments.
    	 * @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.
    	 * }
    	 */
    	public function display_callback( $args, $widget_args = 1 ) {
    		if ( is_numeric( $widget_args ) ) {
    			$widget_args = array( 'number' => $widget_args );
    		}

    		$widget_args = wp_parse_args( $widget_args, array( 'number' => -1 ) );
    		$this->_set( $widget_args['number'] );
    		$instances = $this->get_settings();

    		if ( isset( $instances[ $this->number ] ) ) {
    			$instance = $instances[ $this->number ];

    			/**
    			 * Filters the settings for a particular widget instance.
    			 *
    			 * Returning false will effectively short-circuit display of the widget.
    			 *
    			 * @since 2.8.0
    			 *
    			 * @param array     $instance The current widget instance's settings.
    			 * @param WP_Widget $widget   The current widget instance.
    			 * @param array     $args     An array of default widget arguments.
    			 */
    			$instance = apply_filters( 'widget_display_callback', $instance, $this, $args );

    			if ( false === $instance ) {
    				return;
    			}

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

    			$this->widget( $args, $instance );

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

    	/**
    	 * Handles changed settings (Do NOT override).
    	 *
    	 * @since 2.8.0
    	 *
    	 * @global array $wp_registered_widgets
    	 *
    	 * @param int $deprecated Not used.
    	 */
    	public function update_callback( $deprecated = 1 ) {
    		global $wp_registered_widgets;

    		$all_instances = $this->get_settings();

    		// We need to update the data.
    		if ( $this->updated ) {
    			return;
    		}

    		if ( isset( $_POST['delete_widget'] ) && $_POST['delete_widget'] ) {
    			// Delete the settings for this instance of the widget.
    			if ( isset( $_POST['the-widget-id'] ) ) {
    				$del_id = $_POST['the-widget-id'];
    			} else {
    				return;
    			}

    			if ( isset( $wp_registered_widgets[ $del_id ]['params'][0]['number'] ) ) {
    				$number = $wp_registered_widgets[ $del_id ]['params'][0]['number'];

    				if ( $this->id_base . '-' . $number === $del_id ) {
    					unset( $all_instances[ $number ] );
    				}
    			}
    		} else {
    			if ( isset( $_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;
    	}
    }
    ```

[View all references](https://developer.wordpress.org/reference/files/wp-includes/class-wp-widget.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/class-wp-widget.php#L21)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/class-wp-widget.php#L21-L641)

## 󠀁[Related](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#related)󠁿

| Used by | Description | 
| [WP_Widget_Block](https://developer.wordpress.org/reference/classes/wp_widget_block/)`wp-includes/widgets/class-wp-widget-block.php` |

Core class used to implement a Block widget.

  | 
| [WP_Widget_Custom_HTML](https://developer.wordpress.org/reference/classes/wp_widget_custom_html/)`wp-includes/widgets/class-wp-widget-custom-html.php` |

Core class used to implement a Custom HTML widget.

  | 
| [WP_Widget_Media](https://developer.wordpress.org/reference/classes/wp_widget_media/)`wp-includes/widgets/class-wp-widget-media.php` |

Core class that implements a media widget.

  | 
| [WP_Widget_RSS](https://developer.wordpress.org/reference/classes/wp_widget_rss/)`wp-includes/widgets/class-wp-widget-rss.php` |

Core class used to implement a RSS widget.

  | 
| [WP_Widget_Tag_Cloud](https://developer.wordpress.org/reference/classes/wp_widget_tag_cloud/)`wp-includes/widgets/class-wp-widget-tag-cloud.php` |

Core class used to implement a Tag cloud widget.

  | 
| [WP_Nav_Menu_Widget](https://developer.wordpress.org/reference/classes/wp_nav_menu_widget/)`wp-includes/widgets/class-wp-nav-menu-widget.php` |

Core class used to implement the Navigation Menu widget.

  | 
| [WP_Widget_Recent_Posts](https://developer.wordpress.org/reference/classes/wp_widget_recent_posts/)`wp-includes/widgets/class-wp-widget-recent-posts.php` |

Core class used to implement a Recent Posts widget.

  | 
| [WP_Widget_Recent_Comments](https://developer.wordpress.org/reference/classes/wp_widget_recent_comments/)`wp-includes/widgets/class-wp-widget-recent-comments.php` |

Core class used to implement a Recent Comments widget.

  | 
| [WP_Widget_Calendar](https://developer.wordpress.org/reference/classes/wp_widget_calendar/)`wp-includes/widgets/class-wp-widget-calendar.php` |

Core class used to implement the Calendar widget.

  | 
| [WP_Widget_Text](https://developer.wordpress.org/reference/classes/wp_widget_text/)`wp-includes/widgets/class-wp-widget-text.php` |

Core class used to implement a Text widget.

  | 
| [WP_Widget_Categories](https://developer.wordpress.org/reference/classes/wp_widget_categories/)`wp-includes/widgets/class-wp-widget-categories.php` |

Core class used to implement a Categories widget.

  | 
| [WP_Widget_Archives](https://developer.wordpress.org/reference/classes/wp_widget_archives/)`wp-includes/widgets/class-wp-widget-archives.php` |

Core class used to implement the Archives widget.

  | 
| [WP_Widget_Meta](https://developer.wordpress.org/reference/classes/wp_widget_meta/)`wp-includes/widgets/class-wp-widget-meta.php` |

Core class used to implement a Meta widget.

  | 
| [WP_Widget_Pages](https://developer.wordpress.org/reference/classes/wp_widget_pages/)`wp-includes/widgets/class-wp-widget-pages.php` |

Core class used to implement a Pages widget.

  | 
| [WP_Widget_Links](https://developer.wordpress.org/reference/classes/wp_widget_links/)`wp-includes/widgets/class-wp-widget-links.php` |

Core class used to implement a Links widget.

  | 
| [WP_Widget_Search](https://developer.wordpress.org/reference/classes/wp_widget_search/)`wp-includes/widgets/class-wp-widget-search.php` |

Core class used to implement a Search widget.

  |

[Show 11 more](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#)
[Show less](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#)

## 󠀁[Changelog](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#changelog)󠁿

| Version | Description | 
| [4.4.0](https://developer.wordpress.org/reference/since/4.4.0/) | Moved to its own file from wp-includes/widgets.php | 
| [2.8.0](https://developer.wordpress.org/reference/since/2.8.0/) | Introduced. |

## 󠀁[User Contributed Notes](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#user-contributed-notes)󠁿

 1.  [Skip to note 2 content](https://developer.wordpress.org/reference/classes/wp_widget/?output_format=md&src=bl-po#comment-content-2513)
 2.   [Andy Schmidt](https://profiles.wordpress.org/andy-schmidt/)  [  8 years ago  ](https://developer.wordpress.org/reference/classes/wp_widget/#comment-2513)
 3. [You must log in to vote on the helpfulness of this note](https://login.wordpress.org?redirect_to=https%3A%2F%2Fdeveloper.wordpress.org%2Freference%2Fclasses%2Fwp_widget%2F%23comment-2513)
    Vote results for this note: 2[You must log in to vote on the helpfulness of this note](https://login.wordpress.org?redirect_to=https%3A%2F%2Fdeveloper.wordpress.org%2Freference%2Fclasses%2Fwp_widget%2F%23comment-2513)
 4. When a plug-in is deactivated and then deleted, then the wp_options table might
    continue to hold data about this uninstalled widget. Here is a purge() class method
    that can be called during plug-in uninstall to clean-up the database.
 5.     ```php
        const PLUGIN_SLUG			= 'My_Plugin';			// Short display name for this plug-in, not localized.
    
        class My_Widget extends \WP_Widget 
        {
        	private const BASE_ID 			= 'my_widget';		// Unique, lowercase base ID within WordPress.
    
        	/*
        	 * Destroys subclass options (for plug-in uninstall).
        	 */
        	public static function purge()
        	{
        		// Purge all settings for this widget.
        		if ( ! \delete_option( 'widget_' . self::BASE_ID ) )
        			error_log( __FILE__.': "delete_option()" failed for '.self::BASE_ID );
    
        		// Purge any occurrences of this widget from sidebars.
        		$occurrences = get_option( 'sidebars_widgets' );
        		if ( is_array( $occurrences ) )  {
        			foreach ( $occurrences as $sidebar => $instances ) {
        				if ( is_array( $instances ) ) foreach ( $instances as $key => $widget ) {
        					if ( 1 == preg_match( '/^' . self::BASE_ID . '(?:-\\d+)?$/', $widget ) )
        						// This instance matches the widget's naming pattern.
        						unset( $occurrences[ $sidebar ][ $key ] );
        				}
    
        			}
        			// Rewrite sidebars without occurrences of this widget.
        			update_option( 'sidebars_widgets' , $occurrences );
        		}
        	}
    
        // ... rest of widget code 
        }
    
        /**
         * "uninstall" Action Handler.
         * 
         * @see https://codex.wordpress.org/Function_Reference/register_uninstall_hook
         */
        function on_uninstall(): void 
        {
        	if ( ! \current_user_can( 'activate_plugins' ) ) {
        		\wp_die( __( 'You do not have sufficient permissions to access this page.', PLUGIN_SLUG ), PLUGIN_SLUG );
        	}
    
        	if ( ! \delete_option( PLUGIN_SLUG ) )
        		error_log( __FILE__.': "delete_option()" failed' );
    
        	My_Widget::purge();
        }
    
        /**
         * "activate" Action Handler.
         *
         * @see https://codex.wordpress.org/Function_Reference/register_activation_hook
         */
        function on_activate(): void
        {
        	// Register an uninstall hook for clean-up purposes.
        	\register_uninstall_hook( __FILE__,  __NAMESPACE__.'\on_uninstall' );
        }
    
        /*
         * API Registrations
         */
        if ( \is_blog_admin() ) {
        	// Back-End registrations
        	\register_activation_hook( __FILE__,  __NAMESPACE__.'\on_activate' );
        	\register_deactivation_hook( __FILE__,  __NAMESPACE__.'\on_deactivate' );
    
        // ... add other action/filter hooks
        }
        ```
    
 6.  [Log in to add feedback](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fdeveloper.wordpress.org%2Freference%2Fclasses%2Fwp_widget%2F%3Freplytocom%3D2513%23feedback-editor-2513)

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