EDIT

<?php

/**

 * @file

 * Administrative page callbacks for the External Links module.

 */

/**

 * Page callback: Form constructor for a form to list and reorder external link templates.

 *

 * @ingroup forms

 * @see ext_links_menu()

 * @see ext_links_admin_overview_submit()

 */

function ext_links_admin_overview($form) {

  $link_templates = ext_links_templates();

  $form['#tree'] = TRUE;

  foreach ($link_templates as $id => $link_template) {

    $form['link_templates'][$id]['title'] = array('#markup' => check_plain($link_template->title));

    $form['link_templates'][$id]['link'] = array('#markup' => check_plain($link_template->link));

    $form['link_templates'][$id]['glue'] = array('#markup' => check_plain($link_template->glue));

    $form['link_templates'][$id]['category'] = array('#markup' => check_plain($link_template->category));

      '#title' => $link_template->status == 1 ? t('disable') : t('enable'),

      '#href' => 'admin/config/cdm_dataportal/ext_links/' . $link_template->id . '/status/' . ($link_template->status == 1 ? '0' : '1'));

      '#type' => 'weight',

      '#default_value' => $link_template->weight,

    );

    if($link_template->status != 1){

      $form['link_templates'][$id]['#attributes']['class'][] = 'disabled';

    }

  $form['actions'] = array('#type' => 'actions');

  $form['actions']['submit'] = array('#type' => 'submit', '#value' => t('Save changes'));

  return $form;

}

/**

 * Form submission handler for filter_admin_overview().

 */

function ext_links_admin_overview_submit($form, &$form_state) {

  foreach ($form_state['values']['formats'] as $id => $data) {

    if (is_array($data) && isset($data['weight'])) {

      // Only update if this is a form element with weight.

      db_update('filter_format')

        ->fields(array('weight' => $data['weight']))

        ->condition('format', $id)

        ->execute();

    }

  }

  filter_formats_reset();

  drupal_set_message(t('The text format ordering has been saved.'));

}

 * Page callback: Displays external link template add/edit form.

 *

 * @param object|null $link_template

 *   (optional) An object representing an external link template, with the following properties:

 *   - title: The link title

 *   - link: The link url template.

 *   - glue: The string to concatenate name parts in the URL query string.

 *   - status: (optional) An integer indicating whether the ext link is

 *     enabled (1) or not (0). Defaults to 1.

 *   - weight: (optional) The weight of the external link, which controls its

 *     placement in external link block. If omitted, the weight is set to 0.

 *     Defaults to NULL.

 *

 * @return

 *   A form array.

 *

 * @see filter_menu()

 */

function ext_links_admin_link_template_page($link_template = NULL) {

    $link_template = (object) array(

      'title' => NULL,

      'link' => 'https://',

      'glue' => '',

      'weight' => 0,

      'status' => 1

    );

  }

  return drupal_get_form('ext_links_admin_link_template_form', $link_template);

}

  drupal_set_title(t('Configure the appearance of external links'));

  $form['ext_links_options'] = array(

    '#type' => 'fieldset',

    '#title' => t('External links appearance options'),

    '#collapsible' => FALSE,

    '#collapsed' => FALSE

  );

  $form['ext_links_options']['ext_links_appearance_grouped'] = [

    '#type' => 'checkbox',

    '#title' => t('Show external links grouped by category with headings.'),

    '#default_value' => variable_get('ext_links_appearance_grouped', 1)

  ];

  return system_settings_form($form);

}

/**

 * Form constructor for the External Link add/edit form.

 *

 * @param $link_template

 *   A link template object having the properties:

 *     updated; otherwise, a new external link will be created.

 *   - title: The link title

 *   - link: The link url template.

 *   - glue: The string to concatenate name parts in the URL query string.

 *   - status: (optional) An integer indicating whether the ext link is

 *     enabled (1) or not (0). Defaults to 1.

 *   - weight: (optional) The weight of the external link, which controls its

 *     placement in external link block. If omitted, the weight is set to 0.

 *     Defaults to NULL.

 *

 * @see ext_links_admin_link_template_form_validate()

 * @see ext_links_admin_link_template_form_submit()

 * @ingroup forms

 */

function ext_links_admin_link_template_form($form, &$form_state, $link_template) {

  $form['id'] = array(

    '#type' => 'machine_name',

    '#required' => TRUE,

    '#default_value' => $link_template->id,

    '#maxlength' => 255,

    '#machine_name' => array(

      'exists' => 'ext_link_exists',

    ),

    '#disabled' => !empty($link_template->id),

  );

  $form['title'] = array(

    '#type' => 'textfield',

    '#title' => t('Title'),

    '#default_value' => $link_template->title,

    '#description' => t('The text of the link that will be displayed.'),

    '#required' => TRUE,

  );

  $form['link'] = array(

    '#type' => 'textfield',

    '#title' => t('Link'),

    '#description' => t('The URL of the link to the external resource or service. 

    The species name parts will be appended to this string.<p>E.g. 

    <code>https://external-service.test/images?q=</code> will result in 

    <code>https://external-service.test/images?q=Bellis+perennis</code> when the glue string is set to "+"</p>'),

    '#default_value' => $link_template->link,

    '#required' => TRUE,

  );

  $form['glue'] = array(

    '#type' => 'textfield',

    '#title' => t('Glue'),

    '#description' => t('The string used to concatenate genus and species name parts in the query string.'),

    '#default_value' => $link_template->glue,

    '#required' => false,

  );

  $form['status'] = array(

    '#type' => 'checkbox',

    '#title' => t('Enabled'),

    '#default_value' => $link_template->status

  );

  $form['weight'] = array(

    '#type' => 'weight',

    '#title' => t('Weight'),

    '#default_value' => $link_template->weight,

    '#delta' => 10,

  );

  $form['actions'] = array('#type' => 'actions');

  $form['actions']['submit'] = array('#type' => 'submit', '#value' => t('Save'));

  return $form;

}

/**

 * Form submission handler for ext_links_admin_link_template_form().

 */

function ext_links_admin_link_template_form_submit($form, &$form_state) {

  // Remove unnecessary values.

  form_state_values_clean($form_state);

  // Add the submitted form values to the text link_template, and save it.

  $link_template = $form['#link_template'];

  foreach ($form_state['values'] as $key => $value) {

    $link_template->$key = $value;

  }

  $status = ext_links_save($link_template);

  switch ($status) {

    case SAVED_NEW:

      drupal_set_message(t('Added external link %link_template.', array('%link_template' => $link_template->id)));

      break;

    case SAVED_UPDATED:

      drupal_set_message(t('The text link_template %link_template has been updated.', array('%link_template' => $link_template->id)));

      break;

  }

  drupal_goto('admin/config/cdm_dataportal/ext_links');

 * Sets the status of a link_template.

 *

 * Used as page callback in menu items.

 *

 * @param $link_template

 *    The link template

 * @param $status

 *    The status value to set (values: 1 or 0)

 */

function ext_links_admin_link_template_set_status($link_template, $status){

    $link_template->status = $status === 1 ? 1 : 0;

    ext_links_save($link_template);

    drupal_goto("admin/config/cdm_dataportal/ext_links");

}

 * Returns HTML for the text format administration overview form.

 *

 * @param $variables

 *   An associative array containing:

 *   - form: A render element representing the form.

 *

 * @ingroup themeable

 */

function theme_ext_links_admin_overview($variables) {

  drupal_add_css(drupal_get_path('module', 'ext_links'). '/ext-links.admin.css');

  $rows = array();

  foreach (element_children($form['link_templates']) as $id) {

    $row_class_attributes[] = 'draggable';

    $rows[] = array(

      'data' => array(

        drupal_render($form['link_templates'][$id]['title']),

        drupal_render($form['link_templates'][$id]['link']),

        drupal_render($form['link_templates'][$id]['glue']),

        drupal_render($form['link_templates'][$id]['category']),

        drupal_render($form['link_templates'][$id]['weight']),

        drupal_render($form['link_templates'][$id]['status']),

  }

  $output .= drupal_render_children($form);

  drupal_add_tabledrag('text-format-order', 'order', 'sibling', 'text-format-order-weight');

  return $output;

}