Validate handler for exposed filters
function views_exposed_form_validate(&$form, &$form_state) {
foreach (array(
'field',
'filter',
) as $type) {
$handlers =& $form_state['view']->{$type};
foreach ($handlers as $key => $handler) {
$handlers[$key]
->validateExposed($form, $form_state);
}
}
$exposed_form_plugin = $form_state['exposed_form_plugin'];
$exposed_form_plugin
->exposed_form_validate($form, $form_state);
}