kernel/lib/Form/Container.php
public function isSubmitted() : bool
    {
        if (isset($_POST['validform'.$this->_oForm->getFormNumber()]) && $_POST['validform'.$this->_oForm->getFormNumber()] == 1) {

            return true;
        } else {

            return false;
        }
    }
public function isSubmitted() : bool
    {
        if (isset($_POST['validform'.$this->_oForm->getFormNumber()]) && $_POST['validform'.$this->_oForm->getFormNumber()] == 1) {

            return true;
        } else {

            return false;
        }
    }
if this form is validate and save

@access public
@return boolean