class-acf-field-select.php — Advanced Custom Fields (ACF®) 6.8.7

advanced-custom-fields / includes / fields / class-acf-field-select.php

advanced-custom-fields / includes / fields Last commit date

class-acf-field-select.php

844 lines

1	<?php
2	/**
3	* @package ACF
4	* @author WP Engine
5	*
6	* © 2026 Advanced Custom Fields (ACF®). All rights reserved.
7	* "ACF" is a trademark of WP Engine.
8	* Licensed under the GNU General Public License v2 or later.
9	* https://www.gnu.org/licenses/gpl-2.0.html
10	*/
11
12	if ( ! class_exists( 'acf_field_select' ) ) :
13
14	class acf_field_select extends acf_field {
15
16	/**
17	* Sets up the field type data.
18	*
19	* @since 5.0.0
20	*
21	* @return void
22	*/
23	public function initialize() {
24	$this->name = 'select';
25	$this->label = _x( 'Select', 'noun', 'acf' );
26	$this->category = 'choice';
27	$this->description = __( 'A dropdown list with a selection of choices that you specify.', 'acf' );
28	$this->preview_image = acf_get_url() . '/assets/images/field-type-previews/field-preview-select.png';
29	$this->doc_url = acf_add_url_utm_tags( 'https://www.advancedcustomfields.com/resources/select/', 'docs', 'field-type-selection' );
30	$this->defaults = array(
31	'multiple' => 0,
32	'allow_null' => 0,
33	'choices' => array(),
34	'default_value' => '',
35	'ui' => 0,
36	'ajax' => 0,
37	'placeholder' => '',
38	'return_format' => 'value',
39	'create_options' => 0,
40	'save_options' => 0,
41	);
42
43	add_action( 'wp_ajax_acf/fields/select/query', array( $this, 'ajax_query' ) );
44	add_action( 'wp_ajax_nopriv_acf/fields/select/query', array( $this, 'ajax_query' ) );
45	}
46
47	/**
48	* Enqueues admin scripts for the Select field.
49	*
50	* @since 5.3.2
51	*
52	* @return void
53	*/
54	public function input_admin_enqueue_scripts() {
55	// Bail early if not enqueuing select2.
56	if ( ! acf_get_setting( 'enqueue_select2' ) ) {
57	return;
58	}
59
60	global $wp_scripts;
61
62	$min = defined( 'ACF_DEVELOPMENT_MODE' ) && ACF_DEVELOPMENT_MODE ? '' : '.min';
63	$major = acf_get_setting( 'select2_version' );
64
65	// attempt to find 3rd party Select2 version
66	// - avoid including v3 CSS when v4 JS is already enqueued.
67	if ( isset( $wp_scripts->registered['select2'] ) ) {
68	$major = (int) $wp_scripts->registered['select2']->ver;
69	}
70
71	if ( $major === 3 ) {
72	// Use v3 if necessary.
73	$version = '3.5.2';
74	$script = acf_get_url( "assets/inc/select2/3/select2{$min}.js" );
75	$style = acf_get_url( 'assets/inc/select2/3/select2.css' );
76	} else {
77	// Default to v4.
78	$version = '4.0.13';
79	$script = acf_get_url( "assets/inc/select2/4/select2.full{$min}.js" );
80	$style = acf_get_url( "assets/inc/select2/4/select2{$min}.css" );
81	}
82
83	wp_enqueue_script( 'select2', $script, array( 'jquery' ), $version );
84	wp_enqueue_style( 'select2', $style, '', $version );
85
86	acf_localize_data(
87	array(
88	'select2L10n' => array(
89	'matches_1' => _x( 'One result is available, press enter to select it.', 'Select2 JS matches_1', 'acf' ),
90	/* translators: %d - number of results available in select field */
91	'matches_n' => _x( '%d results are available, use up and down arrow keys to navigate.', 'Select2 JS matches_n', 'acf' ),
92	'matches_0' => _x( 'No matches found', 'Select2 JS matches_0', 'acf' ),
93	'input_too_short_1' => _x( 'Please enter 1 or more characters', 'Select2 JS input_too_short_1', 'acf' ),
94	/* translators: %d - number of characters to enter into select field input */
95	'input_too_short_n' => _x( 'Please enter %d or more characters', 'Select2 JS input_too_short_n', 'acf' ),
96	'input_too_long_1' => _x( 'Please delete 1 character', 'Select2 JS input_too_long_1', 'acf' ),
97	/* translators: %d - number of characters that should be removed from select field */
98	'input_too_long_n' => _x( 'Please delete %d characters', 'Select2 JS input_too_long_n', 'acf' ),
99	'selection_too_long_1' => _x( 'You can only select 1 item', 'Select2 JS selection_too_long_1', 'acf' ),
100	/* translators: %d - maximum number of items that can be selected in the select field */
101	'selection_too_long_n' => _x( 'You can only select %d items', 'Select2 JS selection_too_long_n', 'acf' ),
102	'load_more' => _x( 'Loading more results…', 'Select2 JS load_more', 'acf' ),
103	'searching' => _x( 'Searching…', 'Select2 JS searching', 'acf' ),
104	'load_fail' => _x( 'Loading failed', 'Select2 JS load_fail', 'acf' ),
105	),
106	)
107	);
108	}
109
110	/**
111	* AJAX handler for getting Select field choices.
112	*
113	* @since 5.0.0
114	*
115	* @return void
116	*/
117	public function ajax_query() {
118	$nonce = acf_request_arg( 'nonce', '' );
119	$key = acf_request_arg( 'field_key', '' );
120
121	$is_field_key = acf_is_field_key( $key );
122
123	// Back-compat for field settings.
124	if ( ! $is_field_key ) {
125	if ( ! acf_current_user_can_admin() ) {
126	die();
127	}
128
129	$nonce = '';
130	$key = '';
131	}
132
133	if ( ! acf_verify_ajax( $nonce, $key, $is_field_key, 'select' ) ) {
134	die();
135	}
136
137	acf_send_ajax_results( $this->get_ajax_query( $_POST ) );
138	}
139
140	/**
141	* This function will return an array of data formatted for use in a select2 AJAX response
142	*
143	* @since 5.0.9
144	*
145	* @param array $options An array of options.
146	* @return array A select2 compatible array of options.
147	*/
148	public function get_ajax_query( $options = array() ) {
149	$options = acf_parse_args(
150	$options,
151	array(
152	'post_id' => 0,
153	's' => '',
154	'field_key' => '',
155	'paged' => 1,
156	)
157	);
158
159	$shortcut = apply_filters( 'acf/fields/select/query', array(), $options );
160	$shortcut = apply_filters( 'acf/fields/select/query/key=' . $options['field_key'], $shortcut, $options );
161	if ( ! empty( $shortcut ) ) {
162	return $shortcut;
163	}
164
165	// load field.
166	$field = acf_get_field( $options['field_key'] );
167	if ( ! $field ) {
168	return false;
169	}
170
171	// get choices.
172	$choices = acf_get_array( $field['choices'] );
173	if ( empty( $field['choices'] ) ) {
174	return false;
175	}
176
177	$results = array();
178	$s = null;
179
180	// search.
181	if ( $options['s'] !== '' ) {
182
183	// strip slashes (search may be integer)
184	$s = strval( $options['s'] );
185	$s = wp_unslash( $s );
186	}
187
188	foreach ( $field['choices'] as $k => $v ) {
189
190	// ensure $v is a string.
191	$v = strval( $v );
192
193	// if searching, but doesn't exist.
194	if ( is_string( $s ) && stripos( $v, $s ) === false ) {
195	continue;
196	}
197
198	// append results.
199	$results[] = array(
200	'id' => $k,
201	'text' => $v,
202	);
203	}
204
205	$response = array(
206	'results' => $results,
207	);
208
209	return $response;
210	}
211
212
213	/**
214	* Creates the HTML interface for the field.
215	*
216	* @since 3.6
217	*
218	* @param array $field An array holding all the field's data.
219	* @return void
220	*/
221	public function render_field( $field ) {
222	$value = acf_get_array( $field['value'] );
223	$choices = acf_get_array( $field['choices'] );
224
225	if ( empty( $field['placeholder'] ) ) {
226	$field['placeholder'] = _x( 'Select', 'verb', 'acf' );
227	}
228
229	// Add empty value (allows '' to be selected).
230	if ( empty( $value ) ) {
231	$value = array( '' );
232	}
233
234	// prepend empty choice
235	// - only for single selects
236	// - have tried array_merge but this causes keys to re-index if is numeric (post ID's)
237	if ( $field['allow_null'] && ! $field['multiple'] ) {
238	$choices = array( '' => "- {$field['placeholder']} -" ) + $choices;
239	}
240
241	// clean up choices if using ajax
242	if ( $field['ui'] && $field['ajax'] ) {
243	$minimal = array();
244	foreach ( $value as $key ) {
245	if ( isset( $choices[ $key ] ) ) {
246	$minimal[ $key ] = $choices[ $key ];
247	}
248	}
249	$choices = $minimal;
250	}
251
252	$select = array(
253	'id' => $field['id'],
254	'class' => $field['class'],
255	'name' => $field['name'],
256	'data-ui' => $field['ui'],
257	'data-ajax' => $field['ajax'],
258	'data-multiple' => $field['multiple'],
259	'data-placeholder' => $field['placeholder'],
260	'data-allow_null' => $field['allow_null'],
261	);
262
263	if ( ! empty( $field['aria-label'] ) ) {
264	$select['aria-label'] = $field['aria-label'];
265	}
266
267	if ( $field['multiple'] ) {
268	$select['multiple'] = 'multiple';
269	$select['size'] = 5;
270	$select['name'] .= '[]';
271
272	// Reduce size to single line if UI.
273	if ( $field['ui'] ) {
274	$select['size'] = 1;
275	}
276	}
277
278	if ( ! empty( $field['create_options'] ) && $field['ui'] ) {
279	$select['data-create_options'] = true;
280	}
281
282	// special atts
283	if ( ! empty( $field['readonly'] ) ) {
284	$select['readonly'] = 'readonly';
285	}
286	if ( ! empty( $field['disabled'] ) ) {
287	$select['disabled'] = 'disabled';
288	}
289	if ( ! empty( $field['ajax_action'] ) ) {
290	$select['data-ajax_action'] = $field['ajax_action'];
291	}
292	if ( ! empty( $field['nonce'] ) ) {
293	$select['data-nonce'] = $field['nonce'];
294	}
295	if ( $field['ajax'] && empty( $field['nonce'] ) && acf_is_field_key( $field['key'] ) ) {
296	$select['data-nonce'] = wp_create_nonce( 'acf_field_' . $this->name . '_' . $field['key'] );
297	}
298	if ( ! empty( $field['hide_search'] ) ) {
299	$select['data-minimum-results-for-search'] = '-1';
300	}
301
302	// Hidden input is needed to allow validation to see <select> element with no selected value.
303	if ( $field['multiple'] \|\| $field['ui'] ) {
304	acf_hidden_input(
305	array(
306	'id' => $field['id'] . '-input',
307	'name' => $field['name'],
308	)
309	);
310	}
311
312	$select['value'] = $value;
313	$select['choices'] = $choices;
314
315	if ( ! empty( $field['create_options'] ) && $field['ui'] && is_array( $field['value'] ) ) {
316	foreach ( $field['value'] as $value ) {
317	// Already exists in choices.
318	if ( isset( $field['choices'][ $value ] ) ) {
319	continue;
320	}
321
322	$option = esc_attr( $value );
323
324	$select['choices'][ $option ] = $option;
325	}
326	}
327
328	acf_select_input( $select );
329	}
330
331	/**
332	* Renders the field settings used in the "General" tab.
333	*
334	* @since 3.6
335	*
336	* @param array $field An array holding all the field's data.
337	* @return void
338	*/
339	public function render_field_settings( $field ) {
340
341	// encode choices (convert from array)
342	$field['choices'] = acf_encode_choices( $field['choices'] );
343	$field['default_value'] = acf_encode_choices( $field['default_value'], false );
344
345	// choices
346	acf_render_field_setting(
347	$field,
348	array(
349	'label' => __( 'Choices', 'acf' ),
350	'instructions' => __( 'Enter each choice on a new line.', 'acf' ) . '<br />' . __( 'For more control, you may specify both a value and label like this:', 'acf' ) . '<br /><span class="acf-field-setting-example">' . __( 'red : Red', 'acf' ) . '</span>',
351	'name' => 'choices',
352	'type' => 'textarea',
353	)
354	);
355
356	// default_value
357	acf_render_field_setting(
358	$field,
359	array(
360	'label' => __( 'Default Value', 'acf' ),
361	'instructions' => __( 'Enter each default value on a new line', 'acf' ),
362	'name' => 'default_value',
363	'type' => 'textarea',
364	)
365	);
366
367	// return_format
368	acf_render_field_setting(
369	$field,
370	array(
371	'label' => __( 'Return Format', 'acf' ),
372	'instructions' => __( 'Specify the value returned', 'acf' ),
373	'type' => 'radio',
374	'name' => 'return_format',
375	'layout' => 'horizontal',
376	'choices' => array(
377	'value' => __( 'Value', 'acf' ),
378	'label' => __( 'Label', 'acf' ),
379	'array' => __( 'Both (Array)', 'acf' ),
380	),
381	)
382	);
383
384	acf_render_field_setting(
385	$field,
386	array(
387	'label' => __( 'Select Multiple', 'acf' ),
388	'instructions' => 'Allow content editors to select multiple values',
389	'name' => 'multiple',
390	'type' => 'true_false',
391	'ui' => 1,
392	)
393	);
394	}
395
396	/**
397	* Renders the field settings used in the "Validation" tab.
398	*
399	* @since 6.0
400	*
401	* @param array $field The field settings array.
402	* @return void
403	*/
404	public function render_field_validation_settings( $field ) {
405	acf_render_field_setting(
406	$field,
407	array(
408	'label' => __( 'Allow Null', 'acf' ),
409	'instructions' => '',
410	'name' => 'allow_null',
411	'type' => 'true_false',
412	'ui' => 1,
413	)
414	);
415	}
416
417	/**
418	* Renders the field settings used in the "Presentation" tab.
419	*
420	* @since 6.0
421	*
422	* @param array $field The field settings array.
423	* @return void
424	*/
425	public function render_field_presentation_settings( $field ) {
426	acf_render_field_setting(
427	$field,
428	array(
429	'label' => __( 'Stylized UI', 'acf' ),
430	'instructions' => __( 'Use a stylized checkbox using select2', 'acf' ),
431	'name' => 'ui',
432	'type' => 'true_false',
433	'ui' => 1,
434	)
435	);
436
437	acf_render_field_setting(
438	$field,
439	array(
440	'label' => __( 'Use AJAX to lazy load choices?', 'acf' ),
441	'instructions' => '',
442	'name' => 'ajax',
443	'type' => 'true_false',
444	'ui' => 1,
445	'conditions' => array(
446	'field' => 'ui',
447	'operator' => '==',
448	'value' => 1,
449	),
450	)
451	);
452
453	acf_render_field_setting(
454	$field,
455	array(
456	'label' => __( 'Create Options', 'acf' ),
457	'instructions' => __( 'Allow content editors to create new options by typing in the Select input. Multiple options can be created from a comma separated string.', 'acf' ),
458	'name' => 'create_options',
459	'type' => 'true_false',
460	'ui' => 1,
461	'conditions' => array(
462	array(
463	'field' => 'ui',
464	'operator' => '==',
465	'value' => 1,
466	),
467	array(
468	'field' => 'multiple',
469	'operator' => '==',
470	'value' => 1,
471	),
472	),
473	)
474	);
475
476	acf_render_field_setting(
477	$field,
478	array(
479	'label' => __( 'Save Options', 'acf' ),
480	'instructions' => __( 'Save created options back to the "Choices" setting in the field definition.', 'acf' ),
481	'name' => 'save_options',
482	'type' => 'true_false',
483	'ui' => 1,
484	'conditions' => array(
485	array(
486	'field' => 'ui',
487	'operator' => '==',
488	'value' => 1,
489	),
490	array(
491	'field' => 'multiple',
492	'operator' => '==',
493	'value' => 1,
494	),
495	array(
496	'field' => 'create_options',
497	'operator' => '==',
498	'value' => 1,
499	),
500	),
501	)
502	);
503	}
504
505	/**
506	* Filters the $value after it is loaded from the db.
507	*
508	* @since 3.6
509	*
510	* @param mixed $value The value found in the database.
511	* @param integer\|string $post_id The post_id from which the value was loaded.
512	* @param array $field The field array holding all the field options.
513	* @return mixed
514	*/
515	public function load_value( $value, $post_id, $field ) {
516	// Return an array when field is set for multiple.
517	if ( $field['multiple'] ) {
518	if ( acf_is_empty( $value ) ) {
519	return array();
520	}
521	return acf_array( $value );
522	}
523
524	// Otherwise, return a single value.
525	return acf_unarray( $value );
526	}
527
528	/**
529	* Filters the $field before it is saved to the database.
530	*
531	* @since 3.6
532	*
533	* @param array $field The field array holding all the field options.
534	* @return array
535	*/
536	public function update_field( $field ) {
537	// Decode choices (convert to array).
538	$field['choices'] = acf_decode_choices( $field['choices'] );
539	$field['default_value'] = acf_decode_choices( $field['default_value'], true );
540
541	// Convert back to string for single selects.
542	if ( ! $field['multiple'] ) {
543	$field['default_value'] = acf_unarray( $field['default_value'] );
544	}
545
546	return $field;
547	}
548
549	/**
550	* Filters the $value before it is updated in the db.
551	*
552	* @since 3.6
553	*
554	* @param mixed $value The value which will be saved in the database.
555	* @param integer\|string $post_id The post_id of which the value will be saved.
556	* @param array $field The field array holding all the field options.
557	*
558	* @return mixed
559	*/
560	public function update_value( $value, $post_id, $field ) {
561	// Bail early if no value.
562	if ( empty( $value ) ) {
563	return $value;
564	}
565
566	// Format array of values.
567	// - Parse each value as string for SQL LIKE queries.
568	if ( is_array( $value ) ) {
569	$value = array_map( 'strval', $value );
570	}
571
572	// Save custom options back to the field definition if configured.
573	if ( ! empty( $field['save_options'] ) && is_array( $value ) ) {
574	// Get the raw field, using the ID if present or the key otherwise (i.e. when using JSON).
575	$selector = $field['ID'] ? $field['ID'] : $field['key'];
576	$field = acf_get_field( $selector );
577
578	// Bail if we don't have a valid field or field ID (JSON only).
579	if ( empty( $field['ID'] ) ) {
580	return $value;
581	}
582
583	$this->append_user_choices_to_field( $value, $post_id, $field );
584	}
585
586	return $value;
587	}
588
589	/**
590	* Appends submitter-contributed values to a persisted field's `choices`
591	* array, subject to the `acf/fields/max_appended_choices` cap. Used by
592	* checkbox `save_custom` and select `save_options`. Callers must have
593	* already verified that the setting is enabled and that the field has
594	* an ID (i.e. it's not local/JSON-only).
595	*
596	* @internal Helper for ACF's choice field types; not intended for
597	* external callers. Signature may change without notice.
598	*
599	* @since 6.8.5
600	*
601	* @param array $value Submitted values.
602	* @param integer\|string $post_id The post_id of which the value will be saved.
603	* @param array $field The persisted field array. Must have an ID.
604	* @return void
605	*/
606	public function append_user_choices_to_field( $value, $post_id, $field ) {
607	/**
608	* Filters the maximum number of choices that may be stored on a field
609	* via the checkbox `save_custom`, radio `save_other_choice`, and select
610	* `save_options` settings. Once reached, additional submitter-contributed
611	* values are not appended to the field definition. The submitter's own
612	* field value still saves to their post.
613	*
614	* @since 6.8.5
615	*
616	* @param int $max Maximum number of choices. Default 1000.
617	* @param array $field The field array holding all the field options.
618	* @param integer\|string $post_id The post_id of which the value will be saved.
619	*/
620	$max = (int) apply_filters( 'acf/fields/max_appended_choices', 1000, $field, $post_id );
621
622	$appended = false;
623
624	foreach ( $value as $v ) {
625	// Skip if the raw submitted value matches an existing key,
626	// preserving back-compat for fields whose choices contain
627	// un-normalized keys (e.g. developer-registered with HTML).
628	if ( isset( $field['choices'][ $v ] ) ) {
629	continue;
630	}
631
632	// Unslash (fixes serialize single quote issue) and sanitize.
633	$v = wp_unslash( $v );
634	$v = sanitize_text_field( $v );
635
636	// Skip if the normalized value is empty or already exists.
637	if ( $v === '' \|\| isset( $field['choices'][ $v ] ) ) {
638	continue;
639	}
640
641	// Stop appending once the cap is reached.
642	if ( count( $field['choices'] ) >= $max ) {
643	break;
644	}
645
646	// Append to the field choices.
647	$field['choices'][ $v ] = $v;
648	$appended = true;
649	}
650
651	// Save only if we actually appended a new choice.
652	if ( $appended ) {
653	acf_update_field( $field );
654	}
655	}
656
657	/**
658	* Translates the field settings.
659	*
660	* @since 5.3.2
661	*
662	* @param array $field The main field array.
663	* @return array
664	*/
665	public function translate_field( $field ) {
666	$field['choices'] = acf_translate( $field['choices'] );
667	return $field;
668	}
669
670
671	/**
672	* Filters the $value after it is loaded from the db, and before it is returned to the template.
673	*
674	* @since 3.6
675	*
676	* @param mixed $value The value which was loaded from the database.
677	* @param integer\|string $post_id The post_id from which the value was loaded.
678	* @param array $field The field array holding all the field options.
679	*
680	* @return mixed
681	*/
682	public function format_value( $value, $post_id, $field ) {
683	if ( is_array( $value ) ) {
684	foreach ( $value as $i => $val ) {
685	$value[ $i ] = $this->format_value_single( $val, $post_id, $field );
686	}
687	} else {
688	$value = $this->format_value_single( $value, $post_id, $field );
689	}
690
691	return $value;
692	}
693
694	/**
695	* Formats the value when the select is not a multi-select.
696	*
697	* @since 3.6
698	*
699	* @param mixed $value The value to format.
700	* @param integer\|string $post_id The post_id from which the value was loaded.
701	* @param array $field The field array holding all the field options.
702	* @return mixed
703	*/
704	public function format_value_single( $value, $post_id, $field ) {
705	// Bail early if is empty.
706	if ( acf_is_empty( $value ) ) {
707	return $value;
708	}
709
710	$label = acf_maybe_get( $field['choices'], $value, $value );
711
712	if ( $field['return_format'] === 'label' ) {
713	$value = $label;
714	} elseif ( $field['return_format'] === 'array' ) {
715	$value = array(
716	'value' => $value,
717	'label' => $label,
718	);
719	}
720
721	return $value;
722	}
723
724	/**
725	* Validates select fields updated via the REST API.
726	*
727	* @param boolean $valid The current validity booleean
728	* @param integer $value The value of the field
729	* @param array $field The field array
730	* @return boolean\|WP_Error
731	*/
732	public function validate_rest_value( $valid, $value, $field ) {
733	// rest_validate_request_arg() handles the other types, we just worry about strings.
734	if ( is_null( $value ) \|\| is_array( $value ) ) {
735	return $valid;
736	}
737
738	$option_keys = array_diff(
739	array_keys( $field['choices'] ),
740	array_values( $field['choices'] )
741	);
742
743	$allowed = empty( $option_keys ) ? $field['choices'] : $option_keys;
744
745	if ( ! in_array( $value, $allowed ) ) {
746	$param = sprintf( '%s[%s]', $field['prefix'], $field['name'] );
747	$data = array(
748	'param' => $param,
749	'value' => $value,
750	);
751	$error = sprintf(
752	__( '%1$s is not one of %2$s', 'acf' ),
753	$param,
754	implode( ', ', $allowed )
755	);
756
757	return new WP_Error( 'rest_invalid_param', $error, $data );
758	}
759
760	return $valid;
761	}
762
763	/**
764	* Formats the choices available for the REST API.
765	*
766	* @since 6.2
767	*
768	* @param array $choices The choices for the field.
769	* @return array
770	*/
771	public function format_rest_choices( $choices ) {
772	$keys = array_keys( $choices );
773	$values = array_values( $choices );
774	$int_choices = array();
775
776	if ( array_diff( $keys, $values ) ) {
777	// User has specified custom keys.
778	$choices = $keys;
779	} else {
780	// Default keys, same as value.
781	$choices = $values;
782	}
783
784	// Assume everything is a string by default.
785	$choices = array_map( 'strval', $choices );
786
787	// Also allow integers if is_numeric().
788	foreach ( $choices as $choice ) {
789	if ( is_numeric( $choice ) ) {
790	$int_choices[] = (int) $choice;
791	}
792	}
793
794	return array_merge( $choices, $int_choices );
795	}
796
797	/**
798	* Return the schema array for the REST API.
799	*
800	* @param array $field The main field array.
801	* @return array
802	*/
803	public function get_rest_schema( array $field ) {
804	$schema = array(
805	'type' => array( 'string', 'array', 'int', 'null' ),
806	'required' => ! empty( $field['required'] ),
807	'items' => array(
808	'type' => array( 'string', 'int' ),
809	'enum' => $this->format_rest_choices( $field['choices'] ),
810	),
811	);
812
813	if ( empty( $field['allow_null'] ) ) {
814	$schema['minItems'] = 1;
815	}
816
817	if ( empty( $field['multiple'] ) ) {
818	$schema['maxItems'] = 1;
819	}
820
821	if ( isset( $field['default_value'] ) && '' !== $field['default_value'] ) {
822	$schema['default'] = $field['default_value'];
823	}
824
825	return $schema;
826	}
827
828	/**
829	* Returns an array of JSON-LD Property output types that are supported by this field type.
830	*
831	* @since 6.8
832	*
833	* @return string[]
834	*/
835	public function get_jsonld_output_types(): array {
836	return array( 'Text' );
837	}
838	}
839
840
841	// initialize
842	acf_register_field_type( 'acf_field_select' );
843	endif; // class_exists check
844