CakePHP title_for_layout

I have this function:

function view ( $id )
{
    $this->layout = 'page';

    $this->User->id = $id;

    $this->set('title_for_layout', $username);

    $this->set('users', $this->User->read());
}

What I want to do is show开发者_运维技巧 the username as the title but the current code I have doesn't do this... how do I do it?

$this->User->id = $id;
$this->set('title_for_layout', $this->User->field('username'));

function view ( $id )
{
$this->layout = 'page';

$this->User->id = $id;

$this->set('title_for_layout',  $this->User->field('username'));

$this->set('users', $this->User->read());
}