function form_type_radios_value

Form value callback: Determines the value for a #type radios form element.

Parameters

$element: The form element whose value is being populated.

$input: (optional) The incoming input to populate the form element. If FALSE, the element's default value is returned. Defaults to FALSE.

Return value

The data that will appear in $form_state['values'] for this element, or nothing to use the default.

Related topics

File

includes/form.inc, line 2480

Code

function form_type_radios_value(&$element, $input = FALSE) {
    if ($input !== FALSE) {
        // When there's user input (including NULL), return it as the value.
        // However, if NULL is submitted, _form_builder_handle_input_element() will
        // apply the default value, and we want that validated against #options
        // unless it's empty. (An empty #default_value, such as NULL or FALSE, can
        // be used to indicate that no radio button is selected by default.)
        if (!isset($input) && !empty($element['#default_value'])) {
            $element['#needs_validation'] = TRUE;
        }
        return $input;
    }
    else {
        // For default value handling, simply return #default_value. Additionally,
        // for a NULL default value, set #has_garbage_value to prevent
        // _form_builder_handle_input_element() converting the NULL to an empty
        // string, so that code can distinguish between nothing selected and the
        // selection of a radio button whose value is an empty string.
        $value = isset($element['#default_value']) ? $element['#default_value'] : NULL;
        if (!isset($value)) {
            $element['#has_garbage_value'] = TRUE;
        }
        return $value;
    }
}