How to show a popup in primefaces with the requiredMessages, only if these messages exist?
javascript, jsf, popup, primefaces
Solution
Standard JSF and PrimeFaces does not support request based EL evaluation in `on*` attributes. RichFaces is the only who supports that. Besides, the standard JSF `<h:commandButton>` does not have an `oncomplete` attribute at all. You're probably confusing with PrimeFaces `<p:commandButton>`
There are several ways to achieve this:
Check the condition in the `visible` attribute of the `<p:dialog>` instead.
<p:dialog visible="#{not empty facesContext.messageList}">
or if you want to show validation messages only instead of all messages
<p:dialog visible="#{facesContext.validationFailed}">
Use PrimeFaces `<p:commandButton>` instead, the PrimeFaces JS API supports the `#{facesContext.validationFailed}` condition through the `args` object as well:
<p:commandButton ... oncomplete="if (args.validationFailed) dlg1.show()" />
Problem
I want to show a popup with the requiredMessages of some inputText fields when I click on a submit button. But just only in case of there are those messages. I have tried with bean variable and javascript on the oncomplete tag, but I'm not able to make it work properly. If I put visible="true" in p:dialog, the popup is always displayed, although I try to control it from the commandButton. Now, I have this, but the popup is never displayed: ``` <h:inputText id="Scheme" required="true" requiredMessage="Required."> </h:inputText> <h:commandButton id="submitModify" value="#{msg['systemdetail.modify']}" action="#{sistem.modify}" oncomplete="if (#{facesContext.maximumSeverity != null}) {dlg1.show();}"> </h:commandButton> <p:dialog id="popup" style="text-align:center" widgetVar="dlg1" modal="true"> <h:messages layout="table"/> </p:dialog> ``` How can I do this? Thanks in advance.