Change the Drupal theme according to the day time

I want to write a drupal module which will toggle between 2 themes according to the time of the server.

Please say, w开发者_如何学编程hich hook should I implement.

Should I use

function hook_init(){
    global $custom_theme;
    $custom_theme = (<condition> ? 'theme1' : 'theme2');
}

?

Thanks.

Yes that should work in your module. I have tested it in one of my own and it works fine.