Add hidden values or insert values to fields that are not exposed to user when Using the HelperForm in PRESTASHOP 1.6.3 - prestashop

Question

How to add hidden values or insert values to fields that are not exposed to user such as date_add and date_upd when Using the HelperForm class in PRESTASHOP 1.6.3
I created a new module and now there are two fields in my table which need to be inserted when a new add happens and when an update is done by the user but how to do this when I am using HelperForm class in PRESTASHOP
Below is my render form script
// This form is populated when add or edit is clicked
public function renderForm()
{
$years = Tools::dateYears();
$months = Tools::dateMonths();
$days = Tools::dateDays();
$ticketSeries = Winners::getTicketSeries();
$prdtCategory = Winners::getProductCategory();
$nationality = Winners::getNationality();
$this->fields_form = array(
'tinymce' => true,
'legend' => array(
'title' => $this->l('Configure your Winner'),
'icon' => 'icon-user'
),
'input' => array(
array(
'type' => 'text',
'label' => $this->l('Name'),
'name' => 'name',
'required' => true,
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;?=+()##"°{}_$%:'
),
array(
'type' => 'text',
'label' => $this->l('Ticket No'),
'name' => 'ticket_no',
'required' => true,
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;?=+()##"°{}_$%:'
),
array(
'type' => 'select',
'label' => $this->l('Ticket Series'),
'name' => 'series',
'required' => true,
'options' => array(
'query' => $ticketSeries,
'id' => 'ticket_series_name',
'name' => 'ticket_series_name'
),
'col' => '4',
'hint' => array(
$this->l('The ticket series of each draw !!.')
)
),
array(
'type' => 'select',
'label' => $this->l('Category'),
'name' => 'category',
'required' => true,
'options' => array(
'query' => $prdtCategory,
'id' => 'name',
'name' => 'name'
),
'col' => '4',
'hint' => array(
$this->l('Product Category.')
)
),
array(
'type' => 'date',
'label' => $this->l('Draw Date:'),
'name' => 'draw_date',
'size' => 10,
'required' => true,
'desc' => $this->l('The draw date of this series'),
),
array(
'type' => 'select',
'label' => $this->l('Nationality'),
'name' => 'nationality',
'required' => true,
'options' => array(
'query' => $nationality,
'id' => 'name',
'name' => 'name'
),
'col' => '4',
'hint' => array(
$this->l('Nationality the winner Belongs .')
)
),
array(
'type' => 'textarea',
'label' => $this->l('Testimonial'),
'name' => 'testimonial',
'required' => true,
'autoload_rte' => true,
'rows' => 7,
'cols' => 40,
'hint' => $this->l('Invalid characters:').' <>;=#{}'
), // add tag 'autoload_rte' => true, 'lang' => true, --> lang i removed
// since the editor value did not submit editor
)
);
//d(Tools::getIsset('update'));
if (Tools::getIsset('add') )
$this->fields_form = array_merge(array(
'input' => array(
array(
'type' => 'text',
'label' => $this->l('Add Date'),
'name' => 'date_add',
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;?=+()##"°{}_$%:'
))
));
if (Tools::getIsset('update'))
$this->fields_form = array_merge(array(
'input' => array(
array(
'type' => 'text',
'label' => $this->l('Update Date'),
'name' => 'date_upd',
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;? =+()##"°{}_$%:'
))
));
$this->fields_form['submit'] = array(
'title' => $this->l('Save'),
);
$this->addJqueryUI('ui.datepicker');
return parent::renderForm();
}
I tried something like below yet no use
if (Tools::getIsset('add') )
$this->fields_form = array_merge(array(
'input' => array(
array(
'type' => 'text',
'label' => $this->l('Add Date'),
'name' => 'date_add',
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;?=+()##"°{}_$%:'
))
));
if (Tools::getIsset('update'))
$this->fields_form = array_merge(array(
'input' => array(
array(
'type' => 'text',
'label' => $this->l('Update Date'),
'name' => 'date_upd',
'col' => '4',
'hint' => $this->l('Invalid characters:').' 0-9!<>,;? =+()##"°{}_$%:'
))
));

Answer 1

use 'type' => 'hidden' and provide the value with, for example, 'value' => date("Y-m-d H:i:s")