带有< f:ajax>的JSF2.0只工作一次 [英] JSF2.0 with <f:ajax> only works once
问题描述
我在JSF2.0中的标签有问题，希望有人指出我做错了什么.这是用户界面中的内容:
I'm having a problem with the tag in JSF2.0 and I hope someone can point out what I'm doing wrong. Here's what I've got in the UI:
<h:panelGroup>
<h:form id="theForm">
<h:selectOneMenu id="theMenu" value="#{viewBean.selectedItem}">
<f:ajax event="change" render="selectedItemText"/>
<f:selectItem itemLabel=""/>
<f:selectItems value="#{viewBean.selectableItems}"/>
</h:selectOneMenu>
<h:outputText id="selectedItemText" value="#{viewBean.selectedItemText}" />
</h:form>
</h:panelGroup>
这很好用-我的对话范围内的后备bean有一个方法setSelectedItem，它被调用，并且它在我第一次从菜单中选择另一个项目时就起作用了.输出文本在前端更新，很高兴.但是，对菜单选择的进一步更改不会触发通过ajax调用设置器.我还尝试过在f:ajax标记上使用侦听器进行此操作-该侦听器方法也仅在第一次调用(代码中的断点才能解决).
This is working great - my conversation-scoped backing bean has a method setSelectedItem, and it's called and it does its thing the first time I select a different item from the menu; the output text is updated in the frontend, and I'm happy. However, further changes to the menu selection do not trigger a call to the setter via ajax. I've also tried this with a listener on the f:ajax tag - the listener method is only called that first time as well (breakpoints in the code to figure this out).
我做错了什么吗?
推荐答案
我遇到了类似的问题.
I had a similar problem.
下面的第二个commandButton在具有视图参数的JSF视图中只能使用一次.将<f:param>添加到我的第一个commandButton中解决了该问题.这种情况在BalusC的未必有用的讨论中.
My second commandButton below only works once in the JSF view below that has a view param. Adding <f:param> to my first commandButton solved the problem. This is a situation not covered by BalusC's very helpful discussion.
<!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:ui="http://java.sun.com/jsf/facelets"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html">
<f:view>
<f:metadata>
<f:viewParam name="id" value="#{fooManager.millis}" required="true"/>
</f:metadata>
<h:head>
<meta http-equiv="content-type" content="text/html;charset=utf-8"/>
</h:head>
<h:body>
<h:form id="fooForm">
<h:commandButton
id="barBbutton"
value="foo:test"
action="#{fooManager.test}">
<f:param name="id" value="1"/>
<f:ajax render="fooMillis1"/>
</h:commandButton>
<p>
<h:outputText id="fooMillis1" value="foo:display1: #{fooManager.millis}"/>
</p>
<p>
<h:outputText id="fooMillis2" value="foo:display2: #{fooManager.millis}"/>
</p>
</h:form>
<h:form id="barForm">
<h:commandButton
id="barButton"
value="bar:test"
action="#{barManager.test}">
<f:ajax render="barMillis1"/>
</h:commandButton>
<p>
<h:outputText id="barMillis1" value="bar:display1: #{barManager.millis}"/>
</p>
<p>
<h:outputText id="barMillis2" value="bar:display2: #{barManager.millis}"/>
</p>
</h:form>
</h:body>
</f:view>
</html>
我的FooManager和BarManager看起来相同:
And my FooManager and BarManager look the same:
@ManagedBean
@ViewScoped
public class FooManager {
public long getMillis() {
return millis;
}
public void setMillis(long millis) {
this.millis = millis;
}
public void test() {
setMillis(System.currentTimeMillis());
}
private long millis;
}
当它不起作用时，我的Weblogic/Mojarra库没有给出任何有用的提示.任何地方都没有错误.只是经过无数次尝试，我才想到了一个像上面的第一个一样的工作按钮.
When it is not working, my Weblogic/Mojarra library does not give any helpful hint. There is no error anywhere. It was only after numerous tries that I came up with a working button like the first one above.
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