jsf-2 - 如何对 h :selectOneMenu? 中的值更改执行转换

Question

通常我会做类似下面的事情。单击按钮执行转换。

<!-- view -->
<h:form>
  <h:commandButton action="doit">
    <f:ajax render="@form"/>
  </h:commandButton>
</h:form>

<!-- flow -->
<transition on="doit">...</transition>

如何在(例如)h:selectOneMenu 中更改值时触发转换？

<h:form>
  <h:selectOneMenu value="#{selected}">
    <f:selectItems value="#{items}/>
    <f:ajax event="valueChange" render="@form" />
  </h:selectOneMenu>
</h:form>

编辑: 我考虑过将监听器注册到 f:ajax 并准备 webflow 事件，但是如何使用该事件...？有人帮忙吗？

<h:form>
  <h:selectOneMenu value="#{selected}">
    <f:selectItems value="#{items}/>
    <f:ajax event="valueChange" render="@form" listener="#{bean.changeListener}" />
  </h:selectOneMenu>
</h:form>

Java:

import javax.faces.event.AjaxBehaviorEvent;
import org.springframework.webflow.execution.Event;

public class Bean {
     public void changeListener(AjaxBehaviorEvent event) {
         // prepare webflow event
         Event e = new Event(event.getSource(), "doit");
         // propagate this event... ???
     }
}

Answer 1

我最近遇到了类似的问题，并使用类似的监听器样式处理 primefaces/richfaces 事件。这是一个例子:

    public void changeListener(AjaxBehaviorEvent event) {  
    RequestContext requestContext = RequestContextHolder.getRequestContext();
    RequestControlContext rec = (RequestControlContext) requestContext;
    //place variables you need in next flow phase here; flash,application,session scope
    rec.getFlashScope().put("someVarIneedInNextFlow", varName);
    rec.handleEvent(new Event(this, "flow transition name here, i.e. next-stage"));
    return;
}

那应该过渡到您想要的任何流事件:)