Seam + Ajax4JSF

[pdhaigh]

Hi,

I'm using seam with a4j for dynamic validation etc etc. However, all of my a4j enabled parts of the form are actually written to the database on every change.

E.g.

 <h:form id="webpageForm">
 <f:facet name="afterInvalidField">
 <h:panelGroup><s:message/></h:panelGroup>
 </f:facet>
 <f:facet name="aroundInvalidField">
 <s:span styleClass="error"/>
 </f:facet>
 <s:validateAll>
 <h:panelGrid columns="2" columnClasses="object, value">


 <h:outputText value="Banner #1"/>
 <h:panelGroup id="smallimage1">
 <s:decorate>
 <h:selectOneMenu value="#{webpage.banner_image_1}" required="true">
 <a4j:support event="onchange" reRender="smallimage1" ajaxSingle="true"/>
 <s:selectItems value="#{bannerImages.resultList}"
 var="image" noSelectionLabel="Please select"
 label="#{image.filename}: #{image.altText}"/>
 <s:convertEntity/>
 </h:selectOneMenu>
 </s:decorate>
 <br/>
 <h:graphicImage value="../images/#{webpage.banner_image_1.filename}" alt="#{webpage.banner_image_1.altText}"></h:graphicImage>
 </h:panelGroup>

Changing the drop down will result in the database entry being updated instantly. Can someone tell me why this is the case, and what I need to do (or have missed doing) to prevent it? I want the model to be updated, naturally, but the database should only be written to when I tell it to..

phil

[fernando_jmt]

If you are using a conversation you can start it using manual flush mode.

@Begin(flushMode = FlushModeType.MANUAL)
 public String select(User instance) {
 user = em.find....
 return result;
 }


 @End
 public String create() {
 em.merge(user);
 em.flush();
 return result;
 }

HTH.

[pdhaigh]

thanks,

is there a way to set the flush mode globally?

[matt.drees]

An alternative is to set bypassUpdates="true" on your a4j:support tag. You'll still get a flush, but the model won't have changed.

I tend to use both flushMode = manual and bypassUpdates.