Use this filter cac/acf/format_acf_value to change the ACF value before being displayed as column value.

This filter is used by the ACF add-on.

Usage

/**
 * Filter the ACF value before displaying in the column
 *
 * @param string $value ACF value
 * @param array $field ACF field properties
 * @param int $id Post ID
 * @param string $originalvalue Original ACF value
 * @param object $this Column Object
 */
function my_cac_formatted_acf_value( $value, $acf_field, $id, $originalvalue, $column_object ) {
    // Possibly modify $value
    return $value;
}
add_filter( 'cac/acf/format_acf_value', 'my_cac_formatted_acf_value', 10, 5 );

Example

In this example we will display an actual Google Map, instead of the coordinates, for the google map type.

/**
 * Example: Display an actual Google Map, instead of the coordinates
 *
 */
function my_cac_formatted_acf_value_google_maps( $value, $acf_field, $id, $originalvalue, $column_object ) {
    if ( 'google_map' == $acf_field['type'] ) {
        if ( isset( $originalvalue['lat'] ) && isset( $originalvalue['lng'] ) ) {
            $value = '<iframe width="200" height="170" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="https://maps.google.com/maps?q=' . $originalvalue['lat'] . ',' . $originalvalue['lng'] . '&hl=es;z=14&output=embed"></iframe>';
        }
    }
    return $value;
}
add_filter( 'cac/acf/format_acf_value', 'my_cac_formatted_acf_value_google_maps', 10, 5 );