# Filters and hooks - Swatchline 1.x documentation

> Read swatch data in code, change an attribute's type or swatches, add swatch types, and extend the product page script.

Swatchline's hooks are WordPress filters and actions. Put the examples in a small custom plugin or your child theme's `functions.php`. Swatchline Pro is built on these same hooks.

## Where the data is

| Data | Stored in | Read with |
|---|---|---|
| An attribute's swatch type | The `swatchline_attribute_types` option (attribute id => type; no entry is Dropdown) | `Swatches::attribute_type( $id )`, `Swatches::taxonomy_type( 'pa_colour' )` |
| A value's colour | Term meta `swatchline_color` (#rrggbb) | `Swatches::term_color( $term_id )` |
| A value's image | Term meta `swatchline_image` (attachment id) | `Swatches::term_image( $term_id )` |
| The settings | `swatchline_*` options | `Settings::shape()`, `Settings::size()`… |

The classes are in the `Extendiment\Swatchline` namespace. `Swatches::for_attribute( $product, 'pa_colour', $values )` returns what an attribute shows on a product: its `type` and each option's `value`, `label`, `colors` and `image`, or `null` for a dropdown.

## swatchline_attribute_type

The type of an attribute on a product, before its swatches are built: `select` (dropdown), `color`, `image`, `label` or an add-on's type.

```php
// Sizes are always buttons, whatever the attribute says.
add_filter( 'swatchline_attribute_type', function ( $type, $attribute, $product ) {
	return 'pa_size' === $attribute ? 'label' : $type;
}, 10, 3 );
```

## swatchline_attribute_swatches

The swatches an attribute shows, or `null` for a dropdown. Change an option's `label`, its `colors` (one, or two for a split swatch) or its `image` (an attachment id).

```php
add_filter( 'swatchline_attribute_swatches', function ( $swatches, $product, $attribute ) {
	if ( is_array( $swatches ) && 'pa_colour' === $attribute ) {
		foreach ( $swatches['options'] as $n => $option ) {
			if ( 'rainbow' === $option['value'] ) {
				$swatches['options'][ $n ]['colors'] = array( '#e11d48', '#2563eb' );
			}
		}
	}
	return $swatches;
}, 10, 3 );
```

## swatchline_swatch_types

The types offered on the attribute screen. A new type must be turned into `color`, `image` or `label` in `swatchline_attribute_swatches`; any type Swatchline can't draw shows as a dropdown.

## swatchline_variation and swatchline_load_variations

The product page gets a compact list of the product's variations (`id`, `attributes`, `in_stock`) to cross out what can't be bought. `swatchline_variation` filters each row; `swatchline_load_variations` returns false to leave the list out for a product.

```php
add_filter( 'swatchline_load_variations', function ( $load, $product ) {
	return $product->get_id() !== 123 ? $load : false;
}, 10, 2 );
```

## The product page

| Hook | Use |
|---|---|
| `swatchline_frontend_config` (filter) | The script's settings, `window.swatchlineConfig`: `showSelected`, `soldOut` (`cross`), `i18n` |
| `swatchline_swatches_html` (filter) | `$html, $swatches, $selected, $args`: a group's markup |
| `swatchline_enqueue_scripts` (action) | Fires with Swatchline's styles and script |

The script exposes `window.swatchline`: `state( variations, attributes, chosen, name, value )` returns `ok`, `out` or `none`, and `refresh( form )` brings a form's swatches up to date after you change its dropdowns in code (changing a dropdown and firing its `change` event does that too).

## Admin screens

| Hook | Use |
|---|---|
| `swatchline_term_fields` (action) | `$context` (`add` or `edit`), `$taxonomy`, `$term`: fields after Swatchline's on a term form. `Admin\TermFields::row()` and `color_control()` / `image_control()` draw them the same way |
| `swatchline_save_term` (action) | `$term_id, $taxonomy`: after Swatchline saved a term's fields (nonce and capability checked) |
| `swatchline_term_column` (filter) | `$chips, $term_id`: the Swatch column |
| `swatchline_settings` (filter) | The fields of the Swatches settings section (WooCommerce settings API) |

## swatchline_loaded

Fires once Swatchline has loaded, on `plugins_loaded`, only when WooCommerce is active. Add-ons start there. `SWATCHLINE_VERSION`, `SWATCHLINE_FILE`, `SWATCHLINE_URL` and `SWATCHLINE_DIR` are defined.

Source: https://www.extendiment.com/plugins/swatchline/docs/1.x/filters-and-hooks