Form adding a select backed by a object

General
1

Hi,

I just spent a few hours today banging my head against the wall trying to understand VAADIN selects.

I can get them to behave when they contain a list of enums but when the contain a list of objects I’m having trouble.

  1. If I just pass a list to the select,
    a) everything works fine
    b) but the display is just the classname which is not very user friendly.
    b) Then I try to set a itemCaptionPropertyId but that doesn’t doesn’t work because the default container doesn’t store properties
  2. Next I try to wrap the list with a bean container before I sent it to the select
    a) I get nice labels now
    b) but setValue blows up because it is expecting the Object but sees a BeanId.

What am I missing?

Douglas

2

I can resolve number #1

While adding items to your select, you can set the item caption.
Your code may look like this :


for(Object o : objects) 
{
 select.addItem(o);
 select.setItemCaption(o, "The caption the user see");
}

Hope it’s work.

Éric

3

That makes sense. I guess I was looking for a less brute force method and looked right over the obvious.

Thanks.

4

Hi,

Another choice for the first question could be override toString() method in the bean and return the attribute you want to see in the Select.

For the second question. I use a BeanItemContainer and I do the selection of items in selects in this way.

  2. Create a Container that extends BeanItemContainer
  3. Create the select adding the container created as Container Data Source
  4. Use setValue with the bean you want

The code looks like:

The Container

package org.example.containers;

import java.io.Serializable;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.vaadin.data.util.BeanItemContainer;

import org.example.domain.PersonBean;
import org.example.data.utils.DummyPersonGenerator;

public class PersonContainer extends BeanItemContainer<PersonBean> implements Serializable {
    private static final long serialVersionUID = 1L;

    private static final int PERSON_QUANTITY = 10;
    
    public PersonContainer() {
        super( PersonBean.class );
    }

    public PersonContainer getAllPersons() {
        PersonContainer container = new PersonContainer();
        List<PersonBean> personList = DummyPersonGenerator.createPersonList( PERSON_QUANTITY );
        // Adding items as beans (PersonBean) to container
        for ( PersonBean person : personList ) {
            container.addItem( person );
        }
        // return the container
        return container;
    }

}

The Bean:

package org.example.domain;

public class PersonBean {

    String name;
    
    String surname;
    
    int age;
    
    public PersonBean(String name, String surname, int age) {
        this.name = name;
        this.surname = surname;
        this.age = age;
    }

    // Here the getter and setter methods
    
    @Override
    public String toString() {
        return String.format("%s - %s", name, surname);
    }

}

And finally the Select creation:

Select personSelect = new Select("Person:");
personSelect.setImmediate( true );
personSelect.setContainerDataSource( new PersonContainer().getAllPersons() );

To select an item using the bean you only should do:

PersonBean personToSelect = // the item you want
personSelect.setValue( personToSelect )

Hope it helps.

Javi