Update Link component with new URL

I have a link component like this

private Link eMailThis = new Link ("eMail", new ExternalResource("")); which I update while the user interacts with the vaadin page like this

eMailThis = new Link ("eMail", new ExternalResource("mailto:paul@foo.com?subject=greetings&body=greetings")); I see the original link on the page and can click it, but the URL is not updated. I need to refresh the page so that the updated link becomes part of the HTML shown by the browser. How can I do this?