getting started-firstmidlet.java

RMS移动商务应用开发

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import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
// A first MIDlet with simple text and a few commands.
public class FirstMIDlet extends MIDlet 
       implements CommandListener {

  //The exit, info, and buy commands
  private Command exitCommand; 
  private Command infoCommand; 
  private Command buyCommand;  

  //The display for this MIDlet
  private Display display;

  public FirstMIDlet() {
    display = Display.getDisplay(this);
    exitCommand = new Command("Exit", Command.SCREEN, 1);
    infoCommand = new Command("Info",Command.SCREEN, 2);
    buyCommand = new Command("Buy", Command.SCREEN, 2);
  }

  // Start the MIDlet by creating the TextBox and 
  // associating the exit command and listener.
  public void startApp() {
    TextBox t = new TextBox("FirstMIDlet", 
                    "Welcome to MIDP Programming", 256, 0);
      t.addCommand(exitCommand);
      t.addCommand(infoCommand);
      t.addCommand(buyCommand);
      t.setCommandListener(this);
      display.setCurrent(t);
    }

  // Pause is a no-op because there are no background 
  // activities or record stores to be closed.
  public void pauseApp() { }

  // Destroy must cleanup everything not handled 
  // by the garbage collector.
  // In this case there is nothing to cleanup.
  public void destroyApp(boolean unconditional) { }

  // Respond to commands. Here we are only implementing 
  // the exit command. In the exit command, cleanup and 
  // notify that the MIDlet has been destroyed.
  public void commandAction(Command c, Displayable s) {
    if (c == exitCommand) {
       destroyApp(false);
       notifyDestroyed();
    }
  }
}