我设置了一个表单，用户从下拉列表中选择一个项目。选择该项目后，将填充另一个下拉列表。然后根据从第二个下拉列表中选择的值，可能会或可能不会显示字段集。如果显示了字段集，则有一个字段和一个按钮。通过单击按钮，您可以添加同一字段的另一个副本。一旦有多个，也会显示一个删除一个按钮。我从这里得到了代码的基础：http: //api.drupal.org/api/examples/ajax_example%21ajax_example_graceful_degradation.inc/function/ajax_example_add_more/7
问题是当我第一次单击“添加另一个调查问题”时它可以正常工作并添加一个字段。当我第二次单击它或现在有两个单击删除时，我收到此错误：'已检测到非法选择。请联系网站管理员。'
我究竟做错了什么？
这是我的代码：
function touchpoints_addmetric_form($form, &$form_state, $tp_id) {
$selectedType = isset($form_state['values']['type']) ? $form_state['values']['type'] : FALSE;
$types = db_query('SELECT * FROM {touchpoints_metric_types}') -> fetchAllKeyed(0, 1);
$form['#tree'] = TRUE;
$form['type'] = array(
'#type' => 'select',
'#title' => t('Metric Type'),
'#options' => $types,
'#required'=>TRUE,
'#ajax' => array(
'event' => 'change',
'wrapper' => 'method-wrapper',
'callback' => 'touchpoints_method_callback'
)
);
$form['measurementmethod'] = array(
'#type' => 'select',
'#title' => t('Measurement Method'),
'#required'=>TRUE,
'#prefix' => '<div id="method-wrapper">',
'#suffix' => '</div>',
'#options' => _get_methods($selectedType)
);
$form['survey'] = array('
#type' => 'fieldset',
'#collapsible' => FALSE,
'#states' => array(
'visible' => array(
array(
array(':input[name="measurementmethod"]' => array('value' => '5')),
'xor',
array(':input[name="measurementmethod"]' => array('value' => '6')),
'xor',
array(':input[name="measurementmethod"]' => array('value' => '7'))
)
)
)
);
$form['survey']['contents'] = array(
'#type' => 'fieldset',
'#collapsible' => FALSE,
'#prefix' => '<div id="survey-div">',
'#suffix' => '</div>',
);
if (empty($form_state['num_surveys'])) {
$form_state['num_surveys'] = 1;
}
for ($i = 1; $i <= $form_state['num_surveys']; $i++) {
$form['survey']['contents']['survey_question'][$i] = array(
'#type' => 'textfield',
'#title' => t('Survey Question ' . $i),
'#size' => 70, '#maxlength' => 100,
);
}
$form['survey']['contents']['addsurvey'] = array(
'#type' => 'submit',
'#value' => t('Add Another Survey Question'),
'#submit' => array('touchpoints_metrics_survey_add_one'),
'#limit_validation_errors' => array(),
'#ajax' => array(
'callback' => 'touchpoints_metrics_survey_callback',
'wrapper' => 'survey-div',
),
);
if ($form_state['num_surveys'] > 1) {
$form['survey']['contents']['removesurvey'] = array(
'#type' => 'submit',
'#value' => t('Remove A Survey Question'),
'#submit' => array('touchpoints_metrics_survey_remove_one'),
'#limit_validation_errors' => array(),
'#ajax' => array(
'callback' => 'touchpoints_metrics_survey_callback',
'wrapper' => 'survey-div',
),
);
}
return $form;
}
function _get_methods($selected) {
if ($selected) {
$methods = db_query("SELECT * FROM {touchpoints_m_methods} WHERE mt_id=$selected") -> fetchAllKeyed(0, 2);
} else {
$methods = array();
}
return $methods;
}
function touchpoints_method_callback($form, &$form_state) {
return $form['measurementmethod'];
}
function touchpoints_metrics_survey_add_one($form, &$form_state) {
$form_state['num_surveys']++;
$form_state['rebuild'] = TRUE;
}
function touchpoints_metrics_survey_remove_one($form, &$form_state) {
if ($form_state['num_surveys'] > 1) {
$form_state['num_surveys']--;
}
$form_state['rebuild'] = TRUE;
}
function touchpoints_metrics_survey_callback($form, &$form_state) {
return $form['survey']['contents'];
}