gamemanager.java

J2ME MIDP_Example_Applications

            else
            {
                // After 4 seconds, prompt the user to return to main menu.
                lastText = dict.getString(Dictionary.TEXT_GAME_QUIT_PROMPT);
            }

            drawShortMessage(g, color, winnerText,
                (dict.getString(Dictionary.TEXT_GAME_YOU) + ": " + baseScore),
                (dict.getString(Dictionary.TEXT_GAME_BLOCKS) + ": " +
                blocksScore),
                lastText);
        }
        else
        {
            // The game is still in progress.
            drawGame(g);
        }
    }


    private void drawBackground(Graphics g)
    {
        // The canvas may be bigger than the drawable game.
        // We first erase the entire canvas with WHITE,
        // and next draw a BLACK game board.
        if ((gameWidth < canvas.getWidth()) ||
            (gameHeight < canvas.getHeight()))
        {
            g.setColor(0xFFFFFF); // WHITE
            g.fillRect(0, 0, canvas.getWidth(),
                       canvas.getHeight());
        }

        g.setColor(0x000000); // BLACK
        g.fillRect(0, 0, gameWidth, gameHeight);
    }


    private void drawGame(Graphics g)
    {
        // Draw background
        drawBackground(g);

        // Draw bullets
        Bullet b = (Bullet) (bullets.getFirst());

        while (b != null)
        {
            b.draw(g);
            b = (Bullet) bullets.getNext(b);
        }

        // Draw blocks
        g.setColor(Base.COLOR);
        for (int ix = 0; ix < blocks.size(); ix++)
        {
            Block block = (Block) blocks.elementAt(ix);
            block.draw(g);
        }

        // At the bottom of the screen, either draw the blocks' score or
        // draw the resume message after a pause.
        g.setFont(GAME_FONT);
        if (isPaused)
        {
            // draw the 'Push a key to resume' message after a pause
            String str = dict.getString(Dictionary.TEXT_GAME_RESUME_PROMPT);

            g.setColor(Base.COLOR);
            g.drawString(str, gameWidth / 2, (gameHeight - 2),
                         (Graphics.BOTTOM | Graphics.HCENTER));
        }
        else
        {
            // draw the blocks' score
            StringBuffer buf = new StringBuffer(((showLabelTicks > 0) ?
                (dict.getString(Dictionary.TEXT_GAME_BLOCKS) + ": ") : ""));

            buf.append(blocksScore);
            g.setColor(Block.COLOR);
            g.drawString(buf.toString(), (gameWidth - 2), (gameHeight - 2),
                         (Graphics.BOTTOM | Graphics.RIGHT));
        }


        // At the top of the screen:
        //   Draw the 'canon overheating gauge' + base's score and remaining
        //   lives in the upper left corner of the game screen.
        //   (Depending on showLabelTicks, longer or shorter versions
        //   of the strings are drawn.)

        int yOffset = 2; // pixels
        int xOffset = base.getWidth() + base.getCannonDimension() + yOffset;
        int w = 0;

        // draw 'cannon overheating' gauge (to limit fire rate)
        if (useLimitedFiringRate)
        {
            // set gauge's height and width
            int h = GAME_FONT.getHeight();

            w = (2 * h) / 3;

            int coolDownGaugeHeight = (h * base.getCannonCoolDownTicks()) /
                                      Base.MAX_CANNON_COOLDOWN_TICKS;
            int heatGaugeHeight = h * base.getCannonHeat() /
                                  Base.MAX_CANNON_HEAT;
            int xGauge = gameWidth - w - xOffset;

            if (coolDownGaugeHeight > 0)
            {
                int color = 0x00FFFF; // cooling: CYAN

                drawGauge(g, Base.COLOR, color, xGauge, yOffset, w, h,
                          coolDownGaugeHeight);
            }
            else
            {
                int color = Base.COLOR;

                if (heatGaugeHeight > 0)
                {
                    color = 0xFF55FF; // hot: MAGENTA(ish)
                    drawGauge(g, Base.COLOR, color, xGauge, yOffset, w, h,
                              heatGaugeHeight);
                }
            }
        }

        // draw base score/lives text
        g.setColor(Base.COLOR);

        StringBuffer buf = new StringBuffer((showLabelTicks > 0) ?
            (dict.getString(Dictionary.TEXT_GAME_YOU) + ": ") : "");

        buf.append(baseScore);
        buf.append(" (");
        buf.append(base.getLives());
        buf.append((showLabelTicks > 0) ?
            " " + dict.getString(Dictionary.TEXT_GAME_LIVES) : "");
        buf.append(")");

        g.setColor(Base.COLOR);
        g.drawString(buf.toString(), xOffset, yOffset,
            (Graphics.TOP | Graphics.LEFT));

        // Draw base
        base.draw(g);
    }


    private void drawGauge(Graphics g, int outerColor, int fillColor,
        int x, int y, int w, int h, int gh)
    {
        // Draw the gauge so that it looks a bit like the
        // ASCII art below. ('Y' is the base color (yellow) and
        // 'f' is the fill color of the gauge.)
        //      YYYYYYYY
        //    f Y      Y f
        //    f YffffffY f
        //    f YffffffY f
        //      YYYYYYYY

        g.setColor(outerColor);
        g.drawRect((x + 1), y, (w - 2), (h - 1));
        g.setColor(fillColor);
        g.drawLine(x, (y + 2), x, (y + h - 3));
        g.drawLine((x + w), (y + 2), (x + w), (y + h - 3));
        g.fillRect((x + 2), (y + 1 + h - gh), (w - 3), (gh - 2));
    }


    // Erase the entire canvas, and draw a short final message
    // consisting of two lines of text. No attempt is made to fit the
    // text onto the available canvas space, so the caller must
    // use short text strings.

    private void drawShortMessage(Graphics g, int color, String s1, String s2,
                                  String s3, String s4)
    {
        drawBackground(g);

        g.setColor(color);
        g.setFont(GAME_FONT);

        int fh = GAME_FONT.getHeight();
        // yOffset needed to vertically center 4 lines of text
        int yOffset = (gameHeight - (4 * fh)) / 2;
        int xCenter = gameWidth / 2;
        int anchor = (Graphics.TOP | Graphics.HCENTER);

        g.drawString(s1, xCenter, yOffset, anchor);
        g.drawString(s2, xCenter, yOffset + fh, anchor);
        g.drawString(s3, xCenter, yOffset + (2 * fh), anchor);
        if (s4 != null)
        {
            g.drawString(s4, xCenter, yOffset + (3 * fh), anchor);
        }
    }


    void addBullet(Bullet b)
    {
        bullets.addFirst(b);
        gameEffects.playBullet();
    }


    void doBlockPassed(Block block)
    {
        blocksScore += block.getPoints();
    }


    void closePressed()
    {
        // The GameManager handles the 'closePressed' event from one
        // of two possible sources:
        //  - any softkey press in a NokiaCloseableCanvas (FullCanvas)
        //    indicates that 'close' was pressed
        //  - a CloseableCanvas (Canvas) uses its 'Back' command
        //    to indicate that close was pressed
        // The 'closed' canvas is suspended but not destroyed.
        // It can be resumed and shown on the display again later.
        if (!isPaused)
        {
            pause();
        }

        midlet.gameManagerMainMenu(isGameOver);
    }


    public void keyPressed(int keyCode)
    {
        // When we return to an existing game screen from a 'Continue'
        // in the MainMenu, the game remains paused though displayed.
        // This gives the player time to put their fingers back
        // onto the game keys before the game resumes.
        // The first game key press resumes the game.
        if (isPaused && canvas.isShown())
        {
            resume();
        }

        // The base handles game key presses with gameActionPressed;
        // 'true' means 'game action pressed'.
        base.gameActionPressed(canvas.getGameAction(keyCode), true);
    }


    public void keyReleased(int keyCode)
    {
        // The base handles game key releases with gameActionPressed.
        // 'false' means 'game action released' (i.e. no longer pressed).
        base.gameActionPressed(canvas.getGameAction(keyCode), false);
    }


    // Runnable

    public void run()
    {
        Thread currentThread = Thread.currentThread();

        try
        {
            // This ends when animationThread is set to null, or when
            // it is subsequently set to a new thread; either way, the
            // current thread should terminate.
            while (currentThread == animationThread)
            {
                long startTime = System.currentTimeMillis();

                if (!isPaused)
                {
                    if (canvas.isShown())
                    {
                        // We shouldn't use a transition to the 'not shown'
                        // state to pause the game (see below), until we
                        // are first sure that we have been shown at
                        // some time.
                        if (!hasBeenShown)
                        {
                            hasBeenShown = true;
                        }

                        // We only tick if we are shown.
                        tick();
                    }
                    else
                    {
                        // The game canvas is no longer shown. We should
                        // pause the game since it is no longer visible.
                        // An example is when a system pop-up window like a
                        // low battery warning, incoming phone call, etc.
                        // occurs during the game.
                        // (The method keyPress is used to resume after
                        // such a pause.)
                        if (hasBeenShown)
                        {
                            pause();
                        }
                    }
                }

                // After each tick, we request a repaint.
                // We do not request a repaint when we are not shown.
                //
                // (The repaint below also allows the paint method to print
                // the "Press any key to resume" message after a pause
                // caused by the "!isShown()" code just above,
                // when the game canvas becomes shown again (e.g. after
                // the system pop-up window disappears). The method keyPress
                // causes the actual resume.)
                if (canvas.isShown())
                {
                    canvas.repaint(0, 0, gameWidth, gameHeight);
                    canvas.serviceRepaints();
                }


                long timeTaken = System.currentTimeMillis() - startTime;

                if (timeTaken < MILLIS_PER_TICK)
                {
                    synchronized(this)
                    {
                        wait(MILLIS_PER_TICK - timeTaken);
                    }
                }
                else
                {
                    currentThread.yield();
                }
            }
        }
        catch (InterruptedException e)
        {
        }
    }


    public synchronized void start()
    {
        animationThread = new Thread(this);
        animationThread.start();
        gameEffects.resume();
    }


    public synchronized void stop()
    {
        animationThread = null;
        gameEffects.pause();
    }


    public void pause()
    {
        synchronized(this)
        {
            isPaused = true;
        }
        gameEffects.pause();
    }


    public synchronized boolean isPaused()
    {
        return isPaused;
    }


    public void resume()
    {
        synchronized(this)
        {
            isPaused = false;
        }
        gameEffects.resume();
    }


    public Canvas getCanvas()
    {
        return canvas;
    }
}