spacerdemo.java

本光盘是《J2ME无线移动游戏开发》一书的配套光盘

package ch04;

import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;

public class spacerDemo
    extends MIDlet
    implements CommandListener {
  private Command exitCommand, spacerCommand;
  private Form form;
  public spacerDemo() {
    exitCommand = new Command("Exit", Command.EXIT, 1);
    spacerCommand = new Command("addSpacer", Command.SCREEN, 1);

    form = new Form("spacerDemo");
    form.addCommand(exitCommand);
    form.addCommand(spacerCommand);
    //设置命令监听对象
    form.setCommandListener(this);
    //添加Item对象
    form.append("Login");
    form.append(new TextField("Name", "", 10, TextField.ANY));
    form.append(new TextField("Password", "", 6, TextField.PASSWORD));
  }

  protected void startApp() throws MIDletStateChangeException {
    Display.getDisplay(this).setCurrent(form);
  }

  protected void pauseApp() {
  }

  protected void destroyApp(boolean p1) {
  }

  public void commandAction(Command c, Displayable d) {
    if (c == exitCommand) {
      destroyApp(false);
      notifyDestroyed();
    }
    else if (c == spacerCommand) {
      form.removeCommand(spacerCommand);
      //插入屏幕宽度，高度为5和20象素的Spacer对象
      form.insert(2, new Spacer(form.getWidth(), 5));
      form.insert(1, new Spacer(form.getWidth(), 20));
    }

  }
}