Data-Centric Applications with Vaadin 8

The Vaadin UI

VaadinServlet is configured in the WebConfig class. The UI implementation is realized in the VaadinUI class. For reference, the following is the implementation of the VaadinUI class:

@Title("Call Browser")public class VaadinUI extends UI {    @Override    protected void init(VaadinRequest vaadinRequest) {        VerticalLayout mainLayout = new VerticalLayout();        mainLayout.addComponentsAndExpand(new CallsBrowser());        setContent(mainLayout);    }}

Notice how the UI consists of a VerticalLayout that contains only a CallsBrowser component. We'll start with the following implementation of the CallsBrowser custom component:

public class CallsBrowser extends Composite {    public CallsBrowser() {        TextField filter = new TextField(); filter.setPlaceholder("Client ...