public function login_supervisor()
 {
     if (isset($_POST[tpl_supervisor::username() . '_sup']) && isset($_POST[tpl_supervisor::password() . '_sup'])) {
         $username = $_POST[tpl_supervisor::username() . '_sup'];
         $password = $_POST[tpl_supervisor::password() . '_sup'];
         if (!empty($username) && !empty($password)) {
             $db = new data_base(tpl_supervisor::supervisor(), array(tpl_supervisor::id(), tpl_supervisor::name()), array(tpl_supervisor::username() => $username, tpl_supervisor::password() => $this->hash_password($password), tpl_supervisor::active() => 1));
             $data = $db->get_where();
             if (!empty($data)) {
                 $session = new session_supervisor();
                 $session->new_login_supervisors();
                 $session->set_id_user($data[0][tpl_supervisor::id()]);
                 if ($session->get_login_supervisors()) {
                     echo json_encode(array('valid' => true, 'title' => 'Welcome !!', 'massage' => $data[0][tpl_supervisor::name()]));
                 } else {
                     echo json_encode(array('valid' => false, 'title' => 'Oops !!', 'massage' => 'Was not username & password, please try again'));
                 }
             } else {
                 echo json_encode(array('valid' => false, 'title' => 'Oops !!', 'massage' => 'Was not username & password, please try again'));
             }
         } else {
             echo json_encode(array('valid' => false, 'title' => 'Oops !!', 'massage' => 'Was not username & password, please try again'));
         }
     } else {
         echo json_encode(array('valid' => false, 'title' => 'Oops !!', 'massage' => 'Was not username & password, please try again'));
     }
 }
 public function update()
 {
     $id = $_POST[tpl_supervisor::supervisor() . '_' . tpl_supervisor::id() . '_update'];
     $name = $_POST[tpl_supervisor::supervisor() . '_' . tpl_supervisor::name() . '_update'];
     $id_college = $_POST[tpl_supervisor::supervisor() . '_' . tpl_supervisor::id_college() . '_update'];
     $id_university = $_POST[tpl_supervisor::supervisor() . '_' . tpl_supervisor::id_university() . '_update'];
     $username = $_POST[tpl_supervisor::supervisor() . '_' . tpl_supervisor::username() . '_update'];
     $db = new data_base(tpl_supervisor::supervisor(), array(tpl_supervisor::name() => $name, tpl_supervisor::id_college() => $id_college, tpl_supervisor::id_university() => $id_university, tpl_supervisor::username() => $username), array(tpl_supervisor::id() => $id));
     $results = $db->change();
     if ($results) {
         echo json_encode(array('valid' => 1, 'title' => 'Successfully !!', 'massage' => 'I\'ve been Update ' . $name));
     } else {
         echo json_encode(array('valid' => 0, 'title' => 'Oops !!', 'massage' => 'Was not Update ' . $name . ', please try again'));
     }
 }
                    </div>


                    <div class="form-group">
                        <label
                            for="Edit_NameCategory"><?php 
echo tpl_supervisor::username() . ' ' . tpl_supervisor::supervisor();
?>
                            : </label>
                        <input type="text" class="form-control"
                               id="<?php 
echo tpl_supervisor::supervisor() . '_' . tpl_supervisor::username() . '_update';
?>
"
                               name="<?php 
echo tpl_supervisor::supervisor() . '_' . tpl_supervisor::username() . '_update';
?>
"/>
                    </div>

                    <div class="form-group">
                        <label>College <?php 
echo tpl_supervisor::supervisor();
?>
 : </label>
                        <select name="<?php 
echo tpl_supervisor::supervisor() . '_' . tpl_supervisor::id_university() . '_update';
?>
"
                                id="<?php 
echo tpl_supervisor::supervisor() . '_' . tpl_supervisor::id_university() . '_update';