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ajax - continuation of pressing button twice

Yesterday I posted a question about having to press a button twice to get it to work. I received good help, which is the hallmark of stackoverflow, but the problem still exists. I cut down my code to the bare minimum and the problem still exists. I read closely a BalusC suggestion, hoping that I would find a form inside a form. There is certainly nothing I can see so I will post my code in the hopes that additional pairs of eyes will see something.

I have a template which I call from welcome (the login part). This goes to userInfo which has a command button. This is the command button which I mysteriously have to press twice. On the second push the command button will take me to userPhoto. Everything is trimmed down to the minimum so that I can post it.

master.xthml:

<?xml version="1.0" encoding="UTF-8"?>
<!--
To change this template, choose Tools | Templates
and open the template in the editor.
-->
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui">
<h:head>
<title>Master template</title>
</h:head>
<h:body>
<p:layout fullPage="true" >
    <p:layoutUnit position="north" size="254">
        Top
    </p:layoutUnit>

    <p:layoutUnit position="east" size="50" resizable="true">
        Hello
    </p:layoutUnit>

    <p:layoutUnit position="south" size="30">
        south
    </p:layoutUnit>

    <p:layoutUnit position="center">
        <ui:insert name="AreaOne">Default text</ui:insert>
    </p:layoutUnit>
</p:layout>

</h:body>
</html>

welcome1.xhtml:

<?xml version="1.0" encoding="UTF-8"?>
<!--
To change this template, choose Tools | Templates
and open the template in the editor.
-->
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui">
<ui:composition template="master.xhtml">

    <ui:define name="AreaOne">
        <h:form id="form1">
            <p:commandButton type="submit" value="Login" action="userInfo" />
        </h:form>
        <p:messages />
    </ui:define>
</ui:composition>
</html>

And last but not least userInfo.xhtml with the button which needs to be pressed twice:

<?xml version="1.0" encoding="UTF-8"?>
<!--
To change this template, choose Tools | Templates
and open the template in the editor.
-->
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:p="http://primefaces.org/ui">
<ui:composition template="master.xhtml">

    <ui:define name="AreaOne">
        <h:form id="formP">
            <p:commandButton type="submit" value="photos"  action="userPhoto" />
        </h:form>
        <p:messages />
    </ui:define>
</ui:composition>
</html>

I don't see any form nested inside any other form, but SOMETHING is wrong and I can't figure out what. Maybe BalusC is correct that it has something to do with ajax, but I don't see that either.

Thanks for all the help. Ilan

I added a button on the userPhoto page which goes back to the userInfo page. The Login button is the only one which works one the first press. When I use the command buttons to switch back and forth between userInfo and userPhoto, it always takes 2 pushes. I will show the center of userPhoto

<ui:composition template="master.xhtml">
    <ui:define name="AreaOne">
        <h:form id="form3">
            <p:commandButton type="submit" value="home page" action="userInfo" />
        </h:form>
        <p:messages />
    </ui:define>
</ui:composition>
See Question&Answers more detail:os

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1 Answer

0 votes
by (71.8m points)

You've there a very specific problem. You're fully navigating by ajax instead of by a normal synchronous request and the whole view is replaced with the new view. The forms in the new view does not have the view state anymore which is indeed related to JSF issue 790. It's also not possible to reference the forms in the update of the <p:commandButton> as the forms does not exist in the same view.

After all, it's not recommendable to fully navigate by ajax. It makes your page non-bookmarkable and non-searchbotindexable. I suggest to replace all forms of

<p:commandButton ... action="otherViewId" />

by

<p:button ... outcome="otherViewId" />

This will navigate by normal synchronous requests and will create new views wherein all forms will have their view state. Note that the <p:button> doesn't require a <h:form>, you can omit it if necessary.


Unrelated to the concrete problem, I also suggest to put master.xhtml in the /WEB-INF folder so that the endusers can never request it by entering/guessing its URL in browser address bar. See also Which XHTML files do I need to put in /WEB-INF and which not?


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