--- title: Button order: 14 layout: page --- [[components.button]] = [classname]#Button# ifdef::web[] [.sampler] image:{live-demo-image}[alt="Live Demo", link="http://demo.vaadin.com/sampler/#ui/interaction/button"] endif::web[] The [classname]#Button# component is normally used for initiating some action, such as finalizing input in forms. When the user clicks a button, a [classname]#Button.ClickEvent# is fired, which can be handled with a [interfacename]#Button.ClickListener# in the [methodname]#buttonClick()# method. You can handle button clicks with an anonymous class as follows: [source, java] ---- Button button = new Button("Do not press this button"); button.addClickListener(new Button.ClickListener() { public void buttonClick(ClickEvent event) { Notification.show("Do not press this button again"); } }); // Java 8 button.addClickListener(click -> Notification.show("Do not press this button again")); ---- See the http://demo.vaadin.com/book-examples-vaadin7/book#component.button.basic[on-line example, window="_blank"]. The listener can also be given in the constructor, which is often perhaps simpler. The button component can be styled in many ways, as illustrated in <>. [[figure.component.button.basic]] .Button in Different Styles of Valo Theme image::img/button-example1.png[width=70%, scaledwidth=100%] If you handle several buttons in the same listener, you can differentiate between them either by comparing the [classname]#Button# object reference returned by the [methodname]#getButton()# method of [classname]#Button.ClickEvent# to a kept reference. For a detailed description of these patterns together with some examples, please see <>. == CSS Style Rules [source, css] ---- .v-button { } .v-button-wrap { } .v-button-caption { } ---- A button has an overall [literal]#++v-button++# style. The caption has [literal]#++v-button-caption++# style. There is also an intermediate wrap element, which may help in styling in some cases. Some built-in themes contain a small style, which you can enable by adding [parameter]#Reindeer.BUTTON_SMALL#, etc. The [classname]#BaseTheme# also has a [parameter]#BUTTON_LINK# style, which makes the button look like a hyperlink.