Creating Drupal date popup fields using Drupal form api

Note that the date module is required for this form element type. An additional guide to using these elements is available on drupal.org. For a full list of options available, you'll need to check the module code itself at: date/date_api/date_api_elements.inc::_date_api_element_info()

$form['date'] = array(
    '#type' => 'date_popup',
    '#title' => t('Date'),
    '#date_format' => 'd-m-Y',
    '#date_year_range' => '-100:+0',
    '#date_label_position' => 'none',
    '#default_value' => empty($date)? '' : date('Y-m-d H:i:s', $date),
);
$form['date'] = array(
    '#type' => 'date_popup',
    '#title' => t('Date'),
    '#date_format' => 'd-m-Y',
    '#date_year_range' => '-100:+0',
    '#date_label_position' => 'none',
    '#default_value' => empty($date)? '' : date('Y-m-d H:i:s', $date),
);