package com.vaadin.tests.tickets; import com.vaadin.Application; import com.vaadin.ui.Button; import com.vaadin.ui.Button.ClickEvent; import com.vaadin.ui.UI.LegacyWindow; import com.vaadin.ui.Window; public class Ticket2526 extends Application { @Override public void init() { final LegacyWindow main = new LegacyWindow(); setMainWindow(main); Button b = new Button("Add windows"); b.addListener(new Button.ClickListener() { @Override public void buttonClick(ClickEvent event) { main.addWindow(new Window()); } }); main.addComponent(b); } }