BlackBerry中的老虎机设计

这是一个简单的例子,但你必须自己处理装饰,平滑滚动等。

假设您有6张70x70图像。 简单的BitmapField扩展,用于绘制当前插槽图像、上半个图像和下半个图像:

class SlotField extends BitmapField {
    Bitmap bmp1 = Bitmap.getBitmapResource("img1.png");
    Bitmap bmp2 = Bitmap.getBitmapResource("img2.png");
    Bitmap bmp3 = Bitmap.getBitmapResource("img3.png");
    Bitmap bmp4 = Bitmap.getBitmapResource("img4.png");
    Bitmap bmp5 = Bitmap.getBitmapResource("img5.png");
    Bitmap bmp6 = Bitmap.getBitmapResource("img6.png");

    Bitmap[] bmps = new Bitmap[] { bmp1, bmp2, bmp3, bmp4, bmp5, bmp6 };

    int mPos = 0;

    public SlotField(int position) {
        mPos = position;
    }

    public int getBitmapHeight() {
        return bmp1.getHeight() * 2;
    }

    public int getBitmapWidth() {
        return bmp1.getWidth();
    }

    protected void layout(int width, int height) {
        setExtent(getBitmapWidth(), getBitmapHeight());
    }

    int getNextPos() {
        if (mPos == bmps.length - 1) {
            return 0;
        } else
            return mPos + 1;
    }

    int getPrevPos() {
        if (mPos == 0) {
            return bmps.length - 1;
        } else
            return mPos - 1;
    }

    protected void paint(Graphics g) {
        Bitmap hImg = bmps[getPrevPos()];
        Bitmap mImg = bmps[mPos];
        Bitmap lImg = bmps[getNextPos()];
        g.drawBitmap(0, 0, 70, 35, hImg, 0, 35);
        g.drawBitmap(0, 35, 70, 70, mImg, 0, 0);
        g.drawBitmap(0, 105, 70, 35, lImg, 0, 0);
    }
}

现在,将这些字段放到屏幕上,并用计时器设置动画:

class MainScr extends MainScreen {
    SlotField slot1 = new SlotField(0);
    SlotField slot2 = new SlotField(3);
    SlotField slot3 = new SlotField(5);
    boolean running = false;

    public MainScr() {
        HorizontalFieldManager hField = new HorizontalFieldManager();
        add(hField);

        hField.add(slot1);
        hField.add(slot2);
        hField.add(slot3);

        ButtonField btnRoll = new ButtonField("Roll");
        btnRoll.setChangeListener(new FieldChangeListener() {
            public void fieldChanged(Field field, int context) {
                if (!running)
                    rollSlots();
            }
        });

        add(btnRoll);
    }

    void rollSlots() {
        Timer timer = new Timer();
        final Random rnd = new Random();
        TimerTask ttask1 = new TimerTask() {
            int cycle = 0;

            public void run() {
                slot1.mPos = slot1.getNextPos();
                invalidate();
                cycle++;
                if (cycle >= 100+rnd.nextInt(6))
                    cancel();
            }
        };

        TimerTask ttask2 = new TimerTask() {
            int cycle = 0;

            public void run() {
                slot2.mPos = slot2.getNextPos();
                invalidate();
                cycle++;
                if (cycle >= 100+rnd.nextInt(6))
                    cancel();
            }
        };

        TimerTask ttask3 = new TimerTask() {
            int cycle = 0;

            public void run() {
                slot3.mPos = slot3.getNextPos();
                invalidate();
                cycle++;
                if (cycle >= 100+rnd.nextInt(6))
                    cancel();
            }
        };

        timer.schedule(ttask1, 0, 50);
        timer.schedule(ttask2, 200, 50);
        timer.schedule(ttask3, 400, 50);
    }
}

alt text http://img534.imageshack.us/img534/2172/slots.jpg

有关UI功能,请阅读

Blackberry User Interface Design - Customizable UI?

和

Blackberry - fields layout animation

游戏机上的机械卷盘模拟受以下保护: United States Patent 7452276 . 专利网页链接到40个其他美国和国际专利,在你开始开发你的软件之前,你必须调查这些专利。

在您得到所有不同的美国和国际专利持有者的许可开发您的软件后,您将开发一个长的.gif条带,其中包含不同的图像,您可以在三个或更多的位置快速向下移动。你的软件将不得不扭曲.gif条可见部分的上下边缘,使之看起来像一个机械槽轮。