在Form提交后的变量,很多情况是要展现在jsp页面中,这时Action到Render的变量传递就非常有用。
例如,您在数据库中添加了学生的详细信息。
为了实现这一需求,先创建Form表单(学生的细节,如姓名、出生日期等,通过action url来实现)。
当用户提交表单时,这些数据(学生信息)会在你执行CRUD操作的action方法添加。
添加完成后,需要把一些信息展现到jsp页面。
和v6.2不同的是,action方法里不需要写类似这样的语句:
actionResponse.setRenderParameter("XXX", 变量名);
actionRequest.setAttribute("XXX", 变量名);
举例说明
在Action阶段,我们提交了name变量,然后需要在Render阶段展现在JSP
Java代码
package com.lifiti.portlet; import com.liferay.portal.kernel.log.Log;
import com.liferay.portal.kernel.log.LogFactoryUtil;
import com.liferay.portal.kernel.portlet.bridges.mvc.MVCPortlet;
import com.liferay.portal.kernel.util.ParamUtil; import java.io.IOException;
import java.util.ArrayList;
import java.util.List; import javax.portlet.ActionRequest;
import javax.portlet.ActionResponse;
import javax.portlet.Portlet;
import javax.portlet.PortletException;
import javax.portlet.ProcessAction;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse; import org.osgi.service.component.annotations.Component; @Component(immediate = true, property = { "com.liferay.portlet.display-category=category.sample",
"com.liferay.portlet.instanceable=true", "javax.portlet.requires-namespaced-parameters=false",
"javax.portlet.display-name=com.lifiti.parts Portlet", "javax.portlet.init-param.template-path=/",
"javax.portlet.init-param.view-template=/view.jsp", "javax.portlet.resource-bundle=content.Language",
"javax.portlet.security-role-ref=power-user,user" }, service = Portlet.class)
public class FirstPortlet extends MVCPortlet {
private static final Log _log = LogFactoryUtil.getLog(FirstPortlet.class.getName()); @Override
public void render(RenderRequest request, RenderResponse response) throws PortletException, IOException {
String peopleName = ParamUtil.get(request, "name", "");
String age = ParamUtil.get(request, "age", "");
_log.info("peopleName by ParamUtil in render ==>" + peopleName);
_log.info("age by ParamUtil in render ==>" + age);
_log.info("age By RenderParameter in render ==>" + request.getAttribute("ageBySetParameter")); request.setAttribute("peopleName", peopleName); super.render(request, response);
} @ProcessAction(name = "send")
public void ReceiveData(ActionRequest actionRequest, ActionResponse actionResponse) throws Exception {
String name = ParamUtil.getString(actionRequest, "name");
String age = ParamUtil.getString(actionRequest, "age");
String phone = ParamUtil.getString(actionRequest, "phone"); actionRequest.setAttribute("phone", phone);
//actionResponse.setRenderParameter("ageBySetParameter", age);
List<String> list = new ArrayList<String>();
list.add("tom");
list.add("cat");
list.add("ketty");
actionRequest.setAttribute("personList", list); _log.info(" 开始接收数据");
System.out.println("FirstPortlet.java name = " + name);
System.out.println("FirstPortlet.java age = " + age);
System.out.println("FirstPortlet.java phone = " + phone);
}
}
jsp
<%@page import="com.liferay.portal.kernel.portlet.LiferayPortletMode"%>
<%@page import="com.liferay.portal.kernel.portlet.LiferayWindowState"%>
<%@ include file="/init.jsp" %> <p>
<b><liferay-ui:message key="com_lifiti_parts_ComLifitiPartsmvcportlet.caption"/></b>
</p> <c:set var="submit"><liferay-ui:message key="com_lifiti_parts_ComLifitiPartsmvcportlet.submit"/></c:set> <c:if test="${not empty phone }">
Phone: ${phone} added successfully.
</c:if> <c:if test="${not empty peopleName }">
PeopleName: ${peopleName} added successfully.
</c:if>
<c:forEach var="x" items="${personList}">
<br> ${x}<br>
</c:forEach>
<portlet:actionURL var="sendURL" name="send">
</portlet:actionURL> <form action="${sendURL}" method="post" name="fm">
<aui:input name="name" label="Name" id="name"/>
<aui:input name="age" label="Age" id="age"/>
<input type="text" name="<portlet:namespace/>phone" />
<input type="submit" value="${submit}"></input>
</form>
log:
FirstPortlet.java name = 王昕
FirstPortlet.java age = 1
FirstPortlet.java phone = 123
16:16:59,946 INFO [http-nio-8080-exec-7][FirstPortlet:32] peopleName by ParamUtil in render ==>王昕
16:16:59,947 INFO [http-nio-8080-exec-7][FirstPortlet:33] age by ParamUtil in render ==>1
16:16:59,947 INFO [http-nio-8080-exec-7][FirstPortlet:34] age By RenderParameter in render ==>null
v7.0中这种语句可以不用写:
actionRequest.setAttribute("phone", phone);
actionResponse.setRenderParameter("ageBySetParameter", age);
实际上,只需要2句就能完成数值传递:
String peopleName = ParamUtil.get(request, "name", "");
request.setAttribute("peopleName", peopleName);
直接使用ParamUtil很方便