Advanced Custom Fields Conditional Required Field - itsmereal.com

functions.php

<?php

/**
 * ACF Conditional Required Field
 */

function validate_property_size_field( $valid, $value, $field, $input ){

	// bail early if value is already invalid
	if ( ! $valid ) { return $valid; }

    // We are checking an existing field value
	$property_type = $_POST['acf']['field_5f0aa92348bb6'];

	if ( $property_type == 'Rent' ){
		if ( ! $value ) {
			$valid = __( 'This field is required for Rental Properties' );
		}
    }
	return $valid;

}

add_filter('acf/validate_value/name=property_size',	'validate_property_size_field', 10, 4);

function property_size_required_script_style() { ?>
	<style>
		.af-field-property-size label:after {
			content: '*';
			color: #b9051d !important;
			margin-left: 5px;
		}

		.af-field-property-size label.not-required:after {
			display:none;
		}
	</style>
	<script>
		(function( $ ) {
            $(document).ready(function(){
                $('.af-field-property-available-for .acf-radio-list li').last().click(function(){
                    $('.af-field-property-size label').addClass('not-required');
                });
                $('.af-field-property-available-for .acf-radio-list li').first().click(function(){
                    $('.af-field-property-size label').removeClass('not-required');
                });
            });
        })( jQuery );
	</script>
<?php }

add_action('acf/render_field/name=property_size', 'property_size_required_script_style');