gwt 中FormPanel的使用
package com.google.gwt.sample.hello.client;import com.google.gwt.core.client.EntryPoint;import com.google.gwt.core.client.GWT;import com.google.gwt.user.client.Window;import com.google.gwt.user.client.ui.Button;import com.google.gwt.user.client.ui.ClickListener;import com.google.gwt.user.client.ui.FormHandler;import com.google.gwt.user.client.ui.FormPanel;import com.google.gwt.user.client.ui.FormSubmitCompleteEvent;import com.google.gwt.user.client.ui.FormSubmitEvent;import com.google.gwt.user.client.ui.HorizontalPanel;import com.google.gwt.user.client.ui.RootPanel;import com.google.gwt.user.client.ui.TextBox;import com.google.gwt.user.client.ui.Widget;/** * FormPanel用法 * @author crane.ding * @version 1.0 2008-9-26 */public class Hello implements EntryPoint {public void onModuleLoad() {HorizontalPanel outer = new HorizontalPanel();final FormPanel formPanel = new FormPanel();final TextBox box = new TextBox();final Button button = new Button("ok", new ClickListener() {public void onClick(Widget sender) {formPanel.submit();}});box.setName("textbox");formPanel.setAction(GWT.getModuleBaseURL() + "/myFormHandler");formPanel.setEncoding(FormPanel.ENCODING_URLENCODED);formPanel.setMethod(FormPanel.METHOD_GET);formPanel.addFormHandler(new FormHandler() {public void onSubmit(FormSubmitEvent event) {if (box.getText().trim().equals("")) {Window.alert("请输入");event.setCancelled(true);}}public void onSubmitComplete(FormSubmitCompleteEvent event) {Window.alert(event.getResults());}});outer.add(box);outer.add(button);formPanel.setWidget(outer);RootPanel.get().add(formPanel);}}package com.google.gwt.sample.hello;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * @author crane.ding * @version 1.0 2008-9-26 */public class MyServlet extends HttpServlet {private static final long serialVersionUID = 1L;@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {doPost(req, resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {resp.setContentType("text/plain;charset=UTF-8");resp.getWriter().write(req.getParameter("textbox"));}}<module><inherits name="com.google.gwt.user.User"/><entry-point path="/myFormHandler"/></module>