smart gwt需要xml文件结构

Question

代码工作正常。但是我无法显示来自“setDataURL（”ds / test_data / employees.data.xml“。）的最终数据。请告诉我shud我创建dis文件以及如何创建。

package com.smartgwt.sample.showcase.client;

import com.smartgwt.client.data.DataSource;
import com.smartgwt.client.data.fields.DataSourceFloatField;
import com.smartgwt.client.data.fields.DataSourceIntegerField;
import com.smartgwt.client.data.fields.DataSourceTextField;
import com.smartgwt.client.widgets.Canvas;
import com.smartgwt.client.widgets.grid.CellFormatter;
import com.smartgwt.client.widgets.grid.ListGridRecord;
import com.smartgwt.client.widgets.tree.TreeGrid;
import com.smartgwt.client.widgets.tree.TreeGridField;

import com.google.gwt.i18n.client.NumberFormat;


import com.smartgwt.sample.showcase.shared.FieldVerifier;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DialogBox;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class Showcase implements EntryPoint {
    /**
     * The message displayed to the user when the server cannot be reached or
     * returns an error.
     */
    private static final String SERVER_ERROR = "An error occurred while "
            + "attempting to contact the server. Please check your network "
            + "connection and try again.";

    /**
     * Create a remote service proxy to talk to the server-side Greeting service.
     */
    private final GreetingServiceAsync greetingService = GWT
            .create(GreetingService.class);

    /**
     * This is the entry point method.
     */
    public void onModuleLoad() {


        RootPanel.get().add(getViewPanel());
      }

      public Canvas getViewPanel() {

        EmployeeXmlDS employeesDS = EmployeeXmlDS.getInstance();

        TreeGrid treeGrid = new TreeGrid();
        treeGrid.setCanEdit(true);
        treeGrid.setLoadDataOnDemand(false);
        treeGrid.setWidth(500);
        treeGrid.setHeight(400);
        treeGrid.setDataSource(employeesDS);
        treeGrid.setNodeIcon("icons/16/person.png");
        treeGrid.setFolderIcon("icons/16/person.png");
        treeGrid.setShowOpenIcons(false);
        treeGrid.setShowDropIcons(false);
        treeGrid.setClosedIconSuffix("");
        treeGrid.setAutoFetchData(true);

        TreeGridField nameField = new TreeGridField("Name");
        TreeGridField jobField = new TreeGridField("Job");
        TreeGridField salaryField = new TreeGridField("Salary");
        salaryField.setCellFormatter(new CellFormatter() {
          public String format(Object value, ListGridRecord record, int rowNum, int colNum) {
            if (value != null) {
              NumberFormat nf = NumberFormat.getFormat("#,##0");
              try {
                return "$" + nf.format(((Number) value).longValue());
              } catch (Exception e) {
                return value.toString();
              }
            } else {
              return null;
            }
          }
        });

        treeGrid.setFields(nameField, jobField, salaryField);
        return treeGrid;
      }

    }

    class EmployeeXmlDS extends DataSource {

      private static EmployeeXmlDS instance = null;

      public static EmployeeXmlDS getInstance() {
        if (instance == null) {
          instance = new EmployeeXmlDS("employeesDS");
        }
        return instance;
      }

      public EmployeeXmlDS(String id) {

        setID(id);
        setTitleField("Name");
        setRecordXPath("/List/employee");
        DataSourceTextField nameField = new DataSourceTextField("Name", "Name", 128);

        DataSourceIntegerField employeeIdField = new DataSourceIntegerField("EmployeeId", "Employee ID");
        employeeIdField.setPrimaryKey(true);
        employeeIdField.setRequired(true);

        DataSourceIntegerField reportsToField = new DataSourceIntegerField("ReportsTo", "Manager");
        reportsToField.setRequired(true);
        reportsToField.setForeignKey(id + ".EmployeeId");
        reportsToField.setRootValue("1");

        DataSourceTextField jobField = new DataSourceTextField("Job", "Title", 128);
        DataSourceTextField emailField = new DataSourceTextField("Email", "Email", 128);
        DataSourceTextField statusField = new DataSourceTextField("EmployeeStatus", "Status", 40);
        DataSourceFloatField salaryField = new DataSourceFloatField("Salary", "Salary");
        DataSourceTextField orgField = new DataSourceTextField("OrgUnit", "Org Unit", 128);
        DataSourceTextField genderField = new DataSourceTextField("Gender", "Gender", 7);
        genderField.setValueMap("male", "female");
        DataSourceTextField maritalStatusField = new DataSourceTextField("MaritalStatus",
            "Marital Status", 10);

        setFields(nameField, employeeIdField, reportsToField, jobField, emailField, statusField,
            salaryField, orgField, genderField, maritalStatusField);

        setDataURL("ds/test_data/employees.data.xml");
        setClientOnly(true);
      }
    }