WP_Widget::form_callback( int|array $widget_args = 1 ): string|null
- Since
- 2.8.0
- Source
wp-includes/class-wp-widget.php:503
Compatibility
- WordPress
- since 2.8.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$widget_argsint|arrayoptional- Internal order number of the widget instance, or array of multi-widget arguments. Default 1.Default:
1$numberintNumber increment used for multiples of the same widget.
Return value
string|null
Performance profile
How much work a call to WP_Widget::form_callback() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 30–46
- Plugin surface
- 2 hooks
- Called by
- 0
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 51.
Third-party callbacks on 'widget_form_callback', 'in_widget_form' run inside this call, and their cost is not bounded by anything here.
Nothing in core calls this; the cost is only what you spend yourself.
What it touches
- hookthird-party callbacks
apply_filters()called directly
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_Widget::form_callback() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
$instance === false | 30–34 | wp_parse_args(), ->get_settings(), ->_set(), apply_filters() |
$instance !== false | 42–46 | wp_parse_args(), ->get_settings(), ->_set(), apply_filters(), ->form() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 51 | 30–46 | 3 | |
| 8.5 | 51 | 30–46 | 3 | |
| 8.4 | 51 | 30–46 | 3 | 2 fewer instructions than PHP 8.3 |
| 8.3 | 53 | 32–48 | 3 | |
| 8.2 | 53 | 32–48 | 3 | |
| 8.1 | 53 | 32–48 | 3 | |
| 7.4 | 53 | 32–48 | 3 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Hooks and filters fired · 2
2 hooks fire while WP_Widget::form_callback() runs, in this order:
- apply_filters( widget_form_callback )filterline 530 (+27 into the body)
Filters the widget instance's settings before displaying the control form.
- do_action( in_widget_form )actionline 553 (+50 into the body)
Fires at the end of the widget control form.
Uses · 6
- wp_parse_args()Merges user defined arguments into defaults array.
- apply_filters()Calls the callback functions that have been added to a filter hook.
- do_action_ref_array()Calls the callback functions that have been added to an action hook, specifying arguments in an array.
- WP_Widget::get_settings()Retrieves the settings for all instances of the widget class.
- WP_Widget::_set()Sets the internal order number for the widget instance.
- WP_Widget::form()Outputs the settings update form.
Source code
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; }Changelog
Introduced in 2.8.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 6.7.7 tag, from
src/wp-includes/class-wp-widget.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.