jquery - How can i change the value of a button from external iframe? -

jquery - How can i change the value of a button from external iframe? -

i seek alter value of button within iframe wich loaded site external domain can't access.

i've tried like:

$(document).ready(function(){ $('iframe').contents().find('#button').val('new text'); });

but changes nothing. isn't possible way or not possible because of same origin policy?

jquery button iframe