Ever needed a present a confirmation dialog in a Vaadin application? Here is a way to do that nicely. The ConfirmDialog add-on introduces a configurable way of requesting user confirmation for a button click or just before some important operation. Defaults like size calculation, keyboard bindings and styling are all there, but of course you can provide your own. Take a look at the demo application for sample code and use cases. Supports both two-way (yes,no) and three-way (yes,no,cancel) confirmation. The three-way support was added in version 2.1.x. If you only need a "monolog box", please use the Vaadin's own showNotification method. This is a server-side-only component, so no need to recompile the widgetset.