<?php
/**
* Widget API: WP_Widget base class
*
* @package WordPress
* @subpackage Widgets
* @since 4.4.0
*/
/**
* Core base class extended to register widgets.
*
* This class must be extended for each widget, and WP_Widget::widget() must be overridden.
*
* If adding widget options, WP_Widget::update() and WP_Widget::form() should also be overridden.
*
* @since 2.8.0
* @since 4.4.0 Moved to its own file from wp-includes/widgets.php
*/
#[AllowDynamicProperties]
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 = $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|string $return Default 'noform'. 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;
}
}