import javax.microedition.midlet.*;import javax.microedition.lcdui.*;import java.util.*;public class RepeatEventTest extends MIDlet implements CommandListener, ItemStateListener{        Display display;        MyCanvas myCanvas;        Form form;        ChoiceGroup setRepeat;        Gauge timeInterval;        Command exitCmd;        Command okCmd;        Command backCmd;        Timer repeatTimer;        RepeatTask task;        boolean simRepeat, hasRepeat;        public RepeatEventTest(){                display = Display.getDisplay(this);                exitCmd = new Command("退出", Command.EXIT, 1);                okCmd = new Command("確定", Command.OK, 1);                backCmd = new Command("返回", Command.BACK, 1);                setRepeat = new ChoiceGroup("模擬repeat事件?",Choice.EXCLUSIVE);                setRepeat.append("否", null);                setRepeat.append("是", null);                timeInterval = new Gauge("時間間隔：200ms", true, 10, 0);                myCanvas = new MyCanvas(this);                repeatTimer = new Timer();                task = new RepeatTask();                form = new Form("Repeat事件選擇");                form.append(setRepeat);                form.append(timeInterval);                form.addCommand(exitCmd);                form.addCommand(okCmd);                form.setCommandListener(this);                form.setItemStateListener(this);        }        public void startApp(){                display.setCurrent(form);        }        public void pauseApp(){        }        public void destroyApp(boolean unconditional){        }        public void commandAction(Command c, Displayable d){                if(c == exitCmd){                        destroyApp(true);                        notifyDestroyed();                }                else if(c == okCmd){                        if(setRepeat.getSelectedIndex() == 0)                                simRepeat = false;                        else                                simRepeat = true;                        display.setCurrent(myCanvas);                }                else if(c == backCmd){                        display.setCurrent(form);                }        }        public void itemStateChanged(Item item){                if(item == timeInterval){                        int value = timeInterval.getValue();                        timeInterval.setLabel("時間間隔："+(200+100*value)+"ms");                }        }        class MyCanvas extends Canvas{                int gameAction;                int x, y;                public MyCanvas(RepeatEventTest parent){                        x = getWidth()/2;                        y = getHeight()/2;                        addCommand(backCmd);                        setCommandListener(parent);                }                public void paint(Graphics g){                        g.setColor(0xFFFFFF);                        g.fillRect(0, 0, getWidth(), getHeight());                        g.setColor(0);                        g.fillRect(x, y, 20, 20);                }                public void showNotify(){                        repeatTimer.schedule(task, 0);                }                public void hideNotify(){                        repeatTimer.cancel();                }                public void keyPressed(int keyCode){                        if(simRepeat){                                gameAction = getGameAction(keyCode);                                hasRepeat = true;                        }                        else{                                gameAction = getGameAction(keyCode);                                performGameAction();                        }                }                public void keyReleased(int keyCode){                        if(simRepeat){                                hasRepeat = false;                        }                }                public void keyRepeated(int keyCode){                        if(hasRepeatEvents()){                                keyPressed(keyCode);                        }                }                void performGameAction(){                        switch(gameAction){                        case Canvas.UP:                                if(y < getHeight()) y-=2;                        break;                        case Canvas.DOWN:                                if(y > 0) y+=2;                        break;                        case Canvas.LEFT:                                if(x > 0) x-=2;                        break;                        case Canvas.RIGHT:                                if(y < getWidth()) x+=2;                        break;                        case Canvas.FIRE:                                if(y < getWidth()) x+=2;                        break;                        }                        repaint();                }        }        class RepeatTask extends TimerTask{                public void run(){                        while(true){                                while(hasRepeat){                                        int interval = 200+100*timeInterval.getValue();                                        try{                                                myCanvas.performGameAction();                                                Thread.sleep(interval);                                        }                                        catch(Exception ex){}                                }                        }                }        }}