wp_render_background_support() │ WP 6.4.0

Renders the background styles to the block wrapper. This block support uses the render_block to ensure that it is also applied to non-server-rendered blocks.

No Hooks.

Returns

String. Filtered block content.

Usage

wp_render_background_support( $block_content, $block );

$block_content(string) (required)

Rendered block content.

$block(array) (required)

Block object.

Changelog

wp_render_background_support() wp render background support code ^{WP 6.8.3}

function wp_render_background_support( $block_content, $block ) {
	$block_type                   = WP_Block_Type_Registry::get_instance()->get_registered( $block['blockName'] );
	$block_attributes             = ( isset( $block['attrs'] ) && is_array( $block['attrs'] ) ) ? $block['attrs'] : array();
	$has_background_image_support = block_has_support( $block_type, array( 'background', 'backgroundImage' ), false );

	if (
		! $has_background_image_support ||
		wp_should_skip_block_supports_serialization( $block_type, 'background', 'backgroundImage' ) ||
		! isset( $block_attributes['style']['background'] )
	) {
		return $block_content;
	}

	$background_styles                         = array();
	$background_styles['backgroundImage']      = $block_attributes['style']['background']['backgroundImage'] ?? null;
	$background_styles['backgroundSize']       = $block_attributes['style']['background']['backgroundSize'] ?? null;
	$background_styles['backgroundPosition']   = $block_attributes['style']['background']['backgroundPosition'] ?? null;
	$background_styles['backgroundRepeat']     = $block_attributes['style']['background']['backgroundRepeat'] ?? null;
	$background_styles['backgroundAttachment'] = $block_attributes['style']['background']['backgroundAttachment'] ?? null;

	if ( ! empty( $background_styles['backgroundImage'] ) ) {
		$background_styles['backgroundSize'] = $background_styles['backgroundSize'] ?? 'cover';

		// If the background size is set to `contain` and no position is set, set the position to `center`.
		if ( 'contain' === $background_styles['backgroundSize'] && ! $background_styles['backgroundPosition'] ) {
			$background_styles['backgroundPosition'] = '50% 50%';
		}
	}

	$styles = wp_style_engine_get_styles( array( 'background' => $background_styles ) );

	if ( ! empty( $styles['css'] ) ) {
		// Inject background styles to the first element, presuming it's the wrapper, if it exists.
		$tags = new WP_HTML_Tag_Processor( $block_content );

		if ( $tags->next_tag() ) {
			$existing_style = $tags->get_attribute( 'style' );
			$updated_style  = '';

			if ( ! empty( $existing_style ) ) {
				$updated_style = $existing_style;
				if ( ! str_ends_with( $existing_style, ';' ) ) {
					$updated_style .= ';';
				}
			}

			$updated_style .= $styles['css'];
			$tags->set_attribute( 'style', $updated_style );
			$tags->add_class( 'has-background' );
		}

		return $tags->get_updated_html();
	}

	return $block_content;
}