我有一个采用某些Ajax行为的JSF 2复合组件。我想添加一个listener方法到<f:ajax>标签我复合组件内部,但listener方法应为提供<composite:attribute>的<composite:interface>。
listener
<f:ajax>
<composite:attribute>
<composite:interface>
目前<f:ajax>,我的复合组件内部的标签已被硬编码为这样的侦听器:
<f:ajax event="valueChange" execute="@this" listener="#{controller.genericAjaxEventLogger}" render="#{cc.attrs.ajaxRenderTargets}" />
Bean上的listener方法具有以下签名:
public void genericAjaxEventLogger(AjaxBehaviorEvent event) throws AbortProcessingException { // implementation code... }
我希望复合组件是这样的,以便页面可以提供自己的事件方法,但是我无法弄清楚接口的正确语法。
<f:ajax event="valueChange" execute="@this" listener="#{cc.attrs.ajaxEventListener}" render="#{cc.attrs.ajaxRenderTargets}" />
我怎样才能做到这一点?
解决方案更新:
我采用了BalusC建议的方法,效果很好。相关的片段是:
复合组件中的接口声明
<composite:interface> <composite:attribute name="myattributeUpdatedEventListener" method-signature="void listener()" required="true" /> ... </composite:interface>
我的复合组件中使用的Ajax标签
<f:ajax event="valueChange" execute="@this" listener="#{cc.attrs.myattributeUpdatedEventListener}" render="#{cc.attrs.ajaxRenderTargets}" />
我的页面中使用复合组件的位置
<h:form> <compcomp:myCompositeComponent myattributeUpdatedEventListener="#{myBackingBean.updatedEventListenerXYZ}" /> </h:form>
还有我的后备豆上的方法
public void updatedEventListenerXYZ() { // do something here... }
如果您 可以 摆脱AjaxBehaviorEvent争论,
AjaxBehaviorEvent
public void genericAjaxEventLogger() { // ... }
那么你可以使用
<cc:attribute name="ajaxEventListener" method-signature="void listener()" />
如果参数是强制性的(用于日志记录?),则需要重新指定属性,如下所示
<cc:attribute name="ajaxEventListener" method-signature="void listener(javax.faces.event.AjaxBehaviorEvent)" />
但是,这在这里无法正常工作
<f:ajax listener="#{cc.attrs.ajaxEventListener}" />
在GF 3.1 + Mojarra 2.1.1上:
SEVERE: javax.faces.FacesException: wrong number of arguments at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:89) at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:409) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1534) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98) at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:326) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:227) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:170) at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:822) at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:719) at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1013) at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225) at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104) at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90) at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79) at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54) at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59) at com.sun.grizzly.ContextTask.run(ContextTask.java:71) at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532) at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513) at java.lang.Thread.run(Unknown Source) Caused by: java.lang.IllegalArgumentException: wrong number of arguments at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at com.sun.el.parser.AstValue.invoke(AstValue.java:234) at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:297) at com.sun.faces.facelets.el.ContextualCompositeMethodExpression.invoke(ContextualCompositeMethodExpression.java:177) at com.sun.faces.facelets.tag.TagAttributeImpl$AttributeLookupMethodExpression.invoke(TagAttributeImpl.java:450) at com.sun.faces.facelets.tag.jsf.core.AjaxBehaviorListenerImpl.processAjaxBehavior(AjaxHandler.java:447) at javax.faces.event.AjaxBehaviorEvent.processListener(AjaxBehaviorEvent.java:113) at javax.faces.component.behavior.BehaviorBase.broadcast(BehaviorBase.java:102) at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:760) at javax.faces.component.UICommand.broadcast(UICommand.java:300) at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794) at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259) at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) ... 28 more
我不确定这是否是错误。为此,我需要花费更多时间来确定它。但是,通过创建一个支持组件可以解决该问题MethodExpression,该组件从属性获取并使用正确数量的参数进行调用。这是一个完整的启动示例:
MethodExpression
<ui:component xmlns:f="http://java.sun.com/jsf/core" xmlns:h="http://java.sun.com/jsf/html" xmlns:cc="http://java.sun.com/jsf/composite" xmlns:ui="http://java.sun.com/jsf/facelets" > <cc:interface componentType="testCC"> <cc:attribute name="ajaxEventListener" method-signature="void listener(javax.faces.event.AjaxBehaviorEvent)" /> </cc:interface> <cc:implementation> <h:commandButton value="Submit"> <f:ajax listener="#{cc.ajaxEventListener}" /> </h:commandButton> </cc:implementation> </ui:component>
与
package com.example; import javax.el.MethodExpression; import javax.faces.component.FacesComponent; import javax.faces.component.UINamingContainer; import javax.faces.context.FacesContext; import javax.faces.event.AjaxBehaviorEvent; @FacesComponent(value="testCC") public class TestCC extends UINamingContainer { public void ajaxEventListener(AjaxBehaviorEvent event) { FacesContext context = FacesContext.getCurrentInstance(); MethodExpression ajaxEventListener = (MethodExpression) getAttributes().get("ajaxEventListener"); ajaxEventListener.invoke(context.getELContext(), new Object[] { event }); } }
无论如何,我相信支持组件为实现您已经想到的功能要求的新方法打开了大门;)