Passing component value via aj4:actionparam

[lenyas66]

I need to add a command button to the screen, which will perform DB delete operation without regard to the data entered on the screen. To avoid validation issues I use immediate attribute for it set to true, but then it doesn't update bean value for the single parameter I need to pass to the delete function. Its value does appear on the screen, but I need to assign it to the backing bean variable.

I thought, I could pass it using a4j:actionparam, but it doesn't seem to be working could somebody tell me, what might be wrong?

Code is below. I need to pass the value of comboBox with id "template" to the command button "deleteTemplate".

XHTML:

<

h:panelGrid id="templateParams" columns="8">

<h:outputText value="Templates:" style="font-weight:bold" />

<rich:comboBox id="template" width="160" value="#{qtBeanParam.templateName}" enableManualInput="true" >

<f:selectItems id="templateList" value="#{qtBeanParam.templateList}" />

</rich:comboBox>

<h:outputText value="Owners:" style="font-weight:bold" />

<rich:comboBox id="templateOwner" width="160" value="#{qtBeanParam.templateOwner}" enableManualInput="false" >

<f:selectItems id="templateOwnerList" value="#{qtBeanParam.templateOwnersList}" />

</rich:comboBox>

<a4j:commandButton id="saveTemplate" value="Save"

action="#{qtBeanParam.saveTemplate}" immediate="false" reRender="template,templateList,templateOwner,templateOwnerList"

styleClass="blue-button">

</a4j:commandButton>

<a4j:commandButton id="deleteTemplate" value="Delete"

action="#{qtBeanParam.deleteTemplate}" immediate="true" reRender="template,templateList,templateOwner,templateOwnerList"

styleClass="blue-button">

<a4j:actionparam name="tempname" value="#{template}" assignTo="#{qtBeanParam.templateName}"></a4j:actionparam>

</a4j:commandButton>

</h:panelGrid>

Backing bean method:

public

void deleteTemplate()

{

     final String user = usrSecurityBean.getUserID();

     // templateName is shown on the screen, but is null or empty when at this point

     if ( templateName == null || templateName.equals(""))

     {

          showMessage("piPerformanceReturnsForm:templateParams", "Template name should be selected.");

          return;

     }

...

Thanks a lot in advance,

Leonid

[ilya_shaikovsky]

1) I guess f:setPropertyActionListener will works for you instead of a4j:param. Or you could add converter to your #{template} objects. This caused by the fact that a4j:param encodes params to the client and passes it back on submit. And f:setProp - operates just at server side so it operatees with object.

2) B.t.w. you could use ajaxSingle="true" instead of immediate and use process attribute if will ever need to process single action component and some additional data. But current solution looks better for now.. So this just a note for future

[lenyas66]

Ilya,

I actually, went another way and added valueChangeListener to template combo box to make sure that I always have its value when I attempt to delete it.

Your solution seems to be more simple, but I am not exactly suer how to pass the value of "template" object to "templateName" property using it. Could you provide a small sample?

BTW, I noticed that value of rich:comboBox is not changed after I delete the record from DB and remove it from the list. It still shows on the screen even though I reRender the component. Why would it happen and how could I make sure that it is cleared?

Code is below:

<

h:outputText value="Templates:" style="font-weight:bold" />

<rich:comboBox id="template" width="250" value="#{qtBeanParam.templateName}" enableManualInput="true"

valueChangeListener="#{qtBeanParam.changeTemplate}" >

<a4j:support event="onselect" reRender="template,templateList" ajaxSingle="true" />

<a4j:support event="onchange" reRender="template,templateList" ajaxSingle="true" />

<f:selectItems id="templateList" value="#{qtBeanParam.templateList}" />

</rich:comboBox>

<h:outputText value="Owners:" style="font-weight:bold" />

<rich:comboBox id="templateOwner" width="160" value="#{qtBeanParam.templateOwner}"

immediate="true" enableManualInput="false" >

<f:selectItems id="templateOwnerList" value="#{qtBeanParam.templateOwnersList}" />

</rich:comboBox>

<a4j:commandButton id="saveTemplate" value="Save"

action="#{qtBeanParam.saveTemplate}" immediate="true" reRender="template,templateList,templateOwner,templateOwnerList"

styleClass="blue-button">

</a4j:commandButton>

<a4j:commandButton id="deleteTemplate" value="Delete"

action="#{qtBeanParam.deleteTemplate}" immediate="true" reRender="template,templateList,templateOwner,templateOwnerList"

styleClass="blue-button">

</a4j:commandButton>

[ilya_shaikovsky]

could be caused by immediate=true usage http://ishabalov.blogspot.com/2007/08/sad-story-about-uiinput.html

[lenyas66]

Ilya,

It was exactly what you said and wrapping the button in "a4j:region" eliminated the issue.

Thanks a lot!

Leonid