Java手机游戏编程之MIDP图形设计篇02

　　图5: GameScreen 是一个低级 Canvas（画布）子类

　　3、TicTacToeMIDlet.java

　　TicTacToeMIDlet非常简单：它处理MIDlet的生命周期事件。它根据需要创建屏幕对象并且处理来自屏幕的回调。ChoosePieceScreenDone回调被用来创建GameScreen。quit方法则被GameScreen用来结束游戏。

　　package example.tictactoe;
import java.io.IOException;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
public class TicTacToeMIDlet extends MIDlet {
private ChoosePieceScreen choosePieceScreen;
private GameScreen gameScreen;
public TicTacToeMIDlet()
{
}
public void startApp() {
Displayable current = Display.getDisplay(this).getCurrent();
if (current == null) {
// first time we've been called
// Get the logo image
Image logo = null;
try
{
logo = Image.createImage("/tictactoe.png");
}
catch (IOException e) {
// just use null image
}
Alert splashScreen = new Alert(null, "Tic-Tac-Toe\nForum Nokia", logo, AlertType.INFO);
splashScreen.setTimeout(4000);
// 4 seconds
choosePieceScreen = new ChoosePieceScreen(this);
Display.getDisplay(this).setCurrent(splashScreen, choosePieceScreen);
}
else
{
Display.getDisplay(this).setCurrent(current);
}
}
public void pauseApp() {
}
public void destroyApp(boolean unconditional) {
}
public void quit()
{
destroyApp(false);
notifyDestroyed();
}
public void choosePieceScreenDone(boolean isPlayerCircle)
{
gameScreen = new GameScreen(this, isPlayerCircle);
Display.getDisplay(this).setCurrent(gameScreen);
}
}