Button ClickEvent fire twice

i’m using vaadin 7 alpha 2, and i’ve created a simple button with a notification when i clicked. But the notification showed twice when i hit the button. Is this a bug?

Showing a notification when a Button is clicked seems to work perfectly for me with Vaadin 7 alpha 2 running on Jetty 6.1 in Firefox 11 (with OS X 10.6 and the bundled 1.6 JDK).

Some things you could do to possible help pinpoint the problem is to test with different browsers or application servers (Jetty and Tomcat usually the simplest to get up and running for testing). You could also see what happens in you enable the disableOnClick feature of the Button.