vaadin-framework/documentation/articles/AutoGeneratingAFormBasedOnABeanVaadin6StyleForm.asciidoc

---
title: Auto Generating A Form Based On A Bean Vaadin 6 Style Form
order: 21
layout: page
---

[[auto-generating-a-form-based-on-a-bean-vaadin-6-style-form]]
= Auto-generating a form based on a bean - Vaadin 6 style Form

In Vaadin 6 it is easy to get a completely auto generated form based on
a bean instance by creating a `BeanItem` and passing that to a Form. Using
`FieldGroup` this requires a few extra lines as `FieldGroup` never adds
fields automatically to any layout but instead gives that control to the
developer.

Given a bean such as this `Person`:

[source,java]
....
public class Person {
  private String firstName,lastName;
  private int age;
  // + setters and getters
}
....

You can auto create a form using FieldGroup as follows:

[source,java]
....
public class AutoGeneratedFormUI extends UI {
  @Override
  public void init(VaadinRequest request) {
    VerticalLayout layout = new VerticalLayout();
    setContent(layout);

    FieldGroup fieldGroup = new BeanFieldGroup<Person>(Person.class);

    // We need an item data source before we create the fields to be able to
    // find the properties, otherwise we have to specify them by hand
    fieldGroup.setItemDataSource(new BeanItem<Person>(new Person("John", "Doe", 34)));

    // Loop through the properties, build fields for them and add the fields
    // to this UI
    for (Object propertyId : fieldGroup.getUnboundPropertyIds()) {
      layout.addComponent(fieldGroup.buildAndBind(propertyId));
    }
  }
}
....