How to hook up OptionGroup to a BeanItem?

I am so confused about how to use OptionGroup (radio buttons).

I know how to hook up a String values in a domain object to a BeanItem, and from there set the properties of the BeanItem as the data source for various TextField objects on a layout.

[DomainObject member variables] <--> [JavaBean getter-setter conventions or BeanInfo] <--> [BeanItem properties] <--> [TextFields data sources]

But I can't seem to wrap my head around how to do the same with the Select widgets such as OptionGroup.

What I want is 3 radio buttons that map to an integer value:
( ) Yes
( ) No
( o ) Not yet answered

Those radio buttons should map to an Integer property on my BeanItem, where:
Yes = 1
No = 0
Not yet answered = -1

Can someone give me a clue about the easy way to do this? I've found some hard ways. :(

--Basil Bourque

I think I know how to properly construct the OptionGroup:

// Create the possible values
Collection<Integer> trivalentValues = new ArrayList<Integer>(3);
trivalentValues.add( new Integer(1) );
trivalentValues.add(new Integer(0) );
trivalentValues.add(new Integer(-1));
// Create the widget
this.aliveRadios = new OptionGroup("Are you alive:", trivalentValues  );
this.aliveRadios.setItemCaption(1,"Yes");
this.aliveRadios.setItemCaption(0,"No");
this.aliveRadios.setItemCaption(-1,"Not yet answered");

But I don't understand how to hook this up to the Integer member of a BeanItem.

--Basil Bourque

Hi Basil,

you need two thing to bind an Optiongroup.

First, you need to set a container ( or add manually like you did) to the OptionGroup.
Second, you do the normal binding like any Vaadin component.

from your example :

// Create the possible values
Collection<Integer> trivalentValues = new ArrayList<Integer>(3);
trivalentValues.add( new Integer(1) );
trivalentValues.add(new Integer(0) );
trivalentValues.add(new Integer(-1));
// Create the widget
this.aliveRadios = new OptionGroup("Are you alive:", trivalentValues  );
this.aliveRadios.setItemCaption(1,"Yes");
this.aliveRadios.setItemCaption(0,"No");
this.aliveRadios.setItemCaption(-1,"Not yet answered");
this.aliveRadios.setPropertyDataSource(beanItem.getItemProperty("yourIntegerProperty");

Don't forget to set the immediate mode

setImmediate(true)

.

Did you consider binding the optionGroup with an enumeration instead of an Integer ?

Regards.

Éric

Thanks to Éric for the suggestion to consider using an enum. (I assume he meant an enum rather than Enumeration.) I did indeed learn how to use an enum to back an OptionGroup (radio buttons). Works rather well.

See my answer on StackOverflow for explanation and a couple of complete example apps showing how to populate an OptionGroup with an enum.