demovaders.java

a modefied space invader game

/*
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 * and open the template in the editor.
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/**
 * MIDP 2.0 Sample application
 *
 * @author Alan Newman - [e-mail]
 * @version 1.00 04/05/18
 */
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import java.io.IOException;

public class DemoVaders extends MIDlet implements CommandListener 
{
  private Command exit;
  private Command pause;
  private Command resume;
  
  private VaderCanvas gameCanvas;  
  private Display display;
  private Displayable displayable;

  public DemoVaders()
  {
    display = Display.getDisplay(this);
    
  }

  protected void startApp() throws MIDletStateChangeException {

    getCanvasDisplay();
    display.setCurrent(displayable);

  }

  protected void pauseApp()
  {
    if(displayable!=null)
    {
      display.setCurrent(displayable);
    }
    releaseResource();
  }

  public void destroyApp(boolean unconditional)
  {
  	releaseResource();
  }
  
  private void releaseResource()
  {
  	if(gameCanvas!=null)
    {
      gameCanvas.stop();
    }
  }

  private void getCanvasDisplay()
  {
    try
    {
      if(gameCanvas==null)
      {
        gameCanvas=new VaderCanvas(this);
        //create the commands for both the gameCanvas and pauseCanvas
        exit = new Command("Exit", Command.EXIT, 1);
        pause = new Command("Pause", Command.ITEM, 2);
        gameCanvas.addCommand(exit);
        gameCanvas.addCommand(pause);
        gameCanvas.setCommandListener(this);
      }
      if(!gameCanvas.isRunning())
      {
        gameCanvas.start();
      }
      displayable=gameCanvas;
    }
    catch(IOException ioe)
    {
    }
  }
  public void commandAction(Command command, Displayable d)  {
    if (command==exit)
    {
      destroyApp(true);
      notifyDestroyed();
    }
    else if (command==pause)
    {
      //displayable=pauseCanvas;
      pauseApp();
    }
    else if(command==resume)
    {
      try
      {
        startApp();
      }
      catch (MIDletStateChangeException msce)
      {}
    }

  }
  	

	
}