Description #

Displays a read-only value while still saving the field normally.

The field renders a locked UI but persists its value using a hidden input, ensuring full compatibility with ACF saving logic, REST API output, and frontend forms.

Use Cases #

• Display system-generated values
• Show calculated or derived data
• Expose synchronized API values
• Prevent accidental edits on critical fields
• Display technical identifiers such as IDs, tokens, or hashes

Field Preview #

Locked value rendered as a box, inline text, or code block.
The value is visible but not editable.

How to Use #

1. Add the Read Only (Locked) field to a Field Group
2. Choose the desired Display style
3. Optionally enable the Copy button
4. Optionally select another field as the display source
5. Save the Field Group and edit a post

No custom code is required.

Field Settings #

Setting	Description	Default
Display style	Visual rendering mode (box, inline, code)	box
Placeholder	Text shown when the value is empty	Empty
Show copy button	Enables copy-to-clipboard button	Enabled
Display source	Select which value is displayed	This field value
Other field name/key	Field to mirror (display-only)	Empty

Value & Storage #

• Saved as: Post meta
• Storage type: Hidden input
• Return format: string | null
• Formatting: Display-only formatting does not affect stored value

Arrays and objects are automatically converted to JSON strings.

Output Examples #

PHP (Theme / Plugin) #

$value = get_field('my_read_only_field');
echo esc_html($value);

Twig #

{{ fn('get_field', 'my_read_only_field') }}

Compatibility #

• Repeaters
• Flexible Content
• Options Pages
• Frontend forms (acf_form)
• REST API
• Multisite

Hooks (Developer) #

Hooks Summary #

Hook	Type	Purpose
cfb/field/read_only/defaults	Filter	Modify default settings
cfb/field/read_only/supports	Filter	Modify ACF support flags
cfb/field/read_only/field_type_info	Filter	Override field metadata
cfb/field/read_only/save_value	Filter	Modify value before saving
cfb/field/read_only/display_value_raw	Filter	Modify raw display value
cfb/field/read_only/display_value_string	Filter	Modify final display output
cfb/field/read_only/show_copy	Filter	Control copy button visibility
cfb/field/read_only/effective_post_id	Filter	Control display context
cfb/field/read_only/before_render	Action	Run logic before render
cfb/field/read_only/after_render	Action	Run logic after render

Filters #

Defaults #

Filter: cfb/field/read_only/defaults
Purpose: Override default field configuration globally
When: You want consistent defaults across all instances

add_filter('cfb/field/read_only/defaults', function ($defaults) {
    $defaults['display_style'] = 'inline';
    $defaults['show_copy'] = 0;
    return $defaults;
});

Supports #

Filter: cfb/field/read_only/supports
Purpose: Control ACF support flags such as required
When: Validation or compatibility needs adjustment

add_filter('cfb/field/read_only/supports', function ($supports) {
    $supports['required'] = false;
    return $supports;
});

Field Type Info #

Filter: cfb/field/read_only/field_type_info
Purpose: Override field metadata such as visibility or REST support
When: Customizing how the field appears in the picker

add_filter('cfb/field/read_only/field_type_info', function ($info) {
    $info['public'] = false;
    return $info;
});

Save Value #

Filter: cfb/field/read_only/save_value
Purpose: Modify the value before it is saved
When: Normalizing or sanitizing data

add_filter(
    'cfb/field/read_only/save_value',
    fn ($value) => strtoupper($value)
);

Display Value (Raw) #

Filter: cfb/field/read_only/display_value_raw
Purpose: Modify the value before string conversion
When: Working with numbers, arrays, or objects

add_filter(
    'cfb/field/read_only/display_value_raw',
    fn ($display) => is_numeric($display) ? number_format($display) : $display
);

Display Value (String) #

Filter: cfb/field/read_only/display_value_string
Purpose: Modify the final displayed string
When: Adding prefixes, labels, or formatting

add_filter(
    'cfb/field/read_only/display_value_string',
    fn ($display) => 'ID: ' . $display
);

Copy Button #

Filter: cfb/field/read_only/show_copy
Purpose: Control copy button visibility
When: Restricting copy access by role or context

add_filter(
    'cfb/field/read_only/show_copy',
    fn () => current_user_can('manage_options')
);

Effective Post ID #

Filter: cfb/field/read_only/effective_post_id
Purpose: Define the context used to read mirrored fields
When: Working with options pages, users, or terms

add_filter(
    'cfb/field/read_only/effective_post_id',
    fn () => 'options'
);

Actions #

Before Render #

Action: cfb/field/read_only/before_render
Runs immediately before rendering the field UI

add_action('cfb/field/read_only/before_render', function ($field) {
    // Pre-render logic
});

After Render #

Action: cfb/field/read_only/after_render
Runs after the field UI has been rendered

add_action(
    'cfb/field/read_only/after_render',
    function ($field, $value, $display) {
        // Post-render logic
    },
    10,
    3
);

Assets #

Scripts and styles are automatically enqueued for admin edit screens and frontend forms using acf_form().

Customization #

add_filter(
    'cfb/field/read_only/enqueue_script_args',
    function ($args) {
        $args['deps'][] = 'acf-input';
        return $args;
    }
);

REST API #

• Schema: string | null
• Output: Raw stored value

{
  "my_read_only_field": "ABC-123"
}

Security & Escaping #

• Output is escaped internally
• escaping_html support is enabled
• Template output should still be escaped when applicable

Notes / Limitations #

• Not a disabled input
• Display source does not overwrite stored value
• Formatting affects display only

Changelog #

• 1.0.0 — Initial release