Ajax Events as Behaviors

PrimeFaces provides various component callbacks to respond certains events, for example dialog has a server side closeListener and an attribute like onCloseUpdate. Similarly datatable has rowSelectListener with onRowSelectUpdate option. That is how we are implementing the callbacks, well… until now. The problem with current approach is limiting the page author to use partial processing since there is no onCloseProcess or onRowSelectProcess, also various options like global(flag to notify ajaxStatus), async, disabled are not available. I’ve received many feedback from users regarding this limitation and was planning to use JSF 2.0’s behavior APIs to solve this. After doing a proof of concept work, results are just fine.

Consider a tree component’s nodeSelect event, following is how we do it in 2.x;

    <p:tree nodeSelectListener="#{bean.handleSelect}" onNodeSelectUpdate="sth" ... >

And how it will be in 3.0;

    <p:tree ...>
        <p:ajax event="nodeSelect" listener="#{bean.handleSelect}" update="sth" />
    </p:tree>

Biggest advantage is since you use p:ajax, you can take advantage of handy options like global, async, disabled, oncomplete and we can avoid attribute hell.

Initial implementation of the new approach is at charts item select demo.

There are two important things to note, f:ajax is not supported instead p:ajax and this change breaks backward compatibility but the flexibility it brings justifies it.