title: Prestashop 1.7 renderform by admincontroller error
body: <p>for my module i need to generate a form with helper. I found nothing with my error on the web so... I post again something... </p>
  
  <p>Here my AdminYoutubeHomeController</p>
  
  <pre><code>&lt;?php
  
  
  class AdminYoutubeHomeController extends ModuleAdminController
  {
      public function __construct()
      {
          $this-&gt;bootstrap = true;
          $this-&gt;display = 'view';
          parent::__construct();
          $this-&gt;meta_title = $this-&gt;l('Youtube');
          if (!$this-&gt;module-&gt;active) {
              Tools::redirectAdmin($this-&gt;context-&gt;link-&gt;getAdminLink('AdminHome'));
          }
      }
  
      public function renderView()
      {
          /**
           * If values have been submitted in the form, process.
           */
          if (((bool)Tools::isSubmit('submitYoutubeHomeModule')) == true) {
              $this-&gt;postProcess();
          }
  
          $this-&gt;context-&gt;smarty-&gt;assign([
              'youtube_dir', _PS_MODULE_DIR_.'youtubehome',
              'youtube_embeded' =&gt; "https://www.youtube.com/embed/",
              'youtubeLink' =&gt; Configuration::get('YOUTUBEHOME_LINK_VIDEO')
  
          ]);
  
          return $this-&gt;context-&gt;smarty-&gt;fetch(_PS_MODULE_DIR_.'youtubehome/views/templates/admin/youtubehome.tpl').$this-&gt;renderForm();
      }
  
      /**
       * Create the form that will be displayed in the configuration of your module.
       */
      public function renderForm()
      {
          $helper = new HelperForm();
  
          $helper-&gt;show_toolbar = false;
          $helper-&gt;table = $this-&gt;table;
          $helper-&gt;module = $this;
          $helper-&gt;name_controller = $this-&gt;module-&gt;name;
          $helper-&gt;default_form_language = $this-&gt;context-&gt;language-&gt;id;
          $helper-&gt;allow_employee_form_lang = Configuration::get('PS_BO_ALLOW_EMPLOYEE_FORM_LANG', 0);
  
          $helper-&gt;identifier = $this-&gt;identifier;
          $helper-&gt;submit_action = 'submitYoutubeHomeModule';
  
          $helper-&gt;currentIndex = $this-&gt;context-&gt;link-&gt;getAdminLink('AdminModules', false)
              .'&amp;configure='.$this-&gt;module-&gt;name.'&amp;tab_module='.$this-&gt;module-&gt;tab.'&amp;module_name='.$this-&gt;module-&gt;name;
          $helper-&gt;token = Tools::getAdminTokenLite('AdminModules');
  
          $helper-&gt;tpl_vars = array(
              'fields_value' =&gt; $this-&gt;getConfigFormValues(), /* Add values for your inputs */
              'languages' =&gt; $this-&gt;context-&gt;controller-&gt;getLanguages(),
              'id_language' =&gt; $this-&gt;context-&gt;language-&gt;id,
          );
  
          return $helper-&gt;generateForm(array($this-&gt;getConfigForm()));
      }
  
      /**
       * Create the structure of your form.
       */
      public function getConfigForm()
      {
          return array(
              'form' =&gt; array(
                  'legend' =&gt; array(
                      'title' =&gt; $this-&gt;l('Settings'),
                      'icon' =&gt; 'icon-cogs',
                  ),
                  'input' =&gt; array(
                      array(
                          'col' =&gt; 3,
                          'type' =&gt; 'text',
                          'prefix' =&gt; '&lt;i class="icon icon-youtube-play"&gt;&lt;/i&gt;',
                          'desc' =&gt; $this-&gt;l('Enter your youtube end link'),
                          'name' =&gt; 'YOUTUBEHOME_LINK_VIDEO',
                          'label' =&gt; $this-&gt;l('Link'),
                      ),
                  ),
                  'submit' =&gt; array(
                      'title' =&gt; $this-&gt;l('Save'),
                  ),
              ),
          );
      }
  
      /**
       * Set values for the inputs.
       */
      public function getConfigFormValues()
      {
          return array(
              'YOUTUBEHOME_LINK_VIDEO' =&gt; Configuration::get('YOUTUBEHOME_LINK_VIDEO'),
          );
      }
  
      /**
       * Save form data.
       */
      public function postProcess()
      {
          $form_values = $this-&gt;getConfigFormValues();
  
          foreach (array_keys($form_values) as $key) {
              Configuration::updateValue($key, Tools::getValue($key));
          }
      }
  
  }
  </code></pre>
  
  <p>And here the error </p>
  
  <p><a href="https://i.stack.imgur.com/yIOKl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/yIOKl.png" alt="enter image description here"></a></p>
  
  <p>My tpl file is in modules/youtubehome/views/templates/admin/youtubehome.tpl</p>
  
  <p>I don't want to override the default form. Do you think i have doing something wrong ? </p>
  
  <p><em>EDIT POST</em></p>
  
  <p>Here it's the error with ps_version</p>
  
  <p><a href="https://i.stack.imgur.com/bc9qq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/bc9qq.png" alt="enter image description here"></a></p>