pushpuzzlecanvas.java

里面包含3个手机开发的小游戏 供学习使用

        // Create a mutable image and initialize
        themeImage = Image.createImage(cell * 5, cell);

        Graphics g = themeImage.getGraphics();

        g.setColor(GroundColor0);
        g.fillRect((TILE_GROUND - 1) * cell, 0, cell * TILE_PUSHER, cell);
        g.setColor(PacketColor0);
        g.fillRect(((TILE_PACKET - 1) * cell) + 1, 1, cell - 2, cell - 2);
        g.setColor(StoreColor0);
        g.drawRect(((TILE_STORE - 1) * cell) + 1, 1, cell - 2, cell - 2);
        g.setColor(WallColor0);
        g.fillRect((TILE_WALL - 1) * cell, 0, cell, cell);
        g.setColor(PusherColor0);
        g.fillArc((TILE_PUSHER - 1) * cell, 0, cell, cell, 0, 360);
    }

    /**
     * Setup the theme by reading the images and setting up
     * the sprite and picking the tile size.
     * Uses the current theme index.
     * If the image with the current index can't be found
     * retry with theme = 0.
     *
     * @param image containing all the frames used for the board.
     */
    private void setupTheme() {
        if (sprite != null) {
            layers.remove(sprite);
            sprite = null;
        }

        if (theme > 0) {
            try {
                StringBuffer name = new StringBuffer("/example/pushpuzzle/images/Theme-");
                name.append(theme);
                name.append(".png");
                themeImage = Image.createImage(name.toString());

                // Cells are square using the minimum of the width and height
                int h = themeImage.getHeight();
                int w = themeImage.getWidth();
                cell = (w < h) ? w : h;
            } catch (IOException e) {
                theme = 0;
                setupTheme0();
            }
        } else {
            setupTheme0();
        }

        sprite = new Sprite(themeImage, cell, cell);
        sprite.defineReferencePixel(cell / 2, cell / 2);

        int[] seq = new int[]{TILE_PUSHER - 1};
        sprite.setFrameSequence(seq);
        layers.insert(sprite, 0);
    }

    /**
     * Return the Screen to display scores.
     * It returns a screen with the current scores.
     *
     * @return a screen initialized with the current score information.
     */
    public Screen getScoreScreen() {

        int currPushes = board.getPushes();
        int bestPushes = score.getPushes();
        int currMoves = board.getMoves();
        int bestMoves = score.getMoves();
        boolean newbest = solved && ((bestPushes == 0) || (currPushes < bestPushes));

        // Temp until form can do setItem
        Form scoreForm = new Form(null);

        scoreForm.append(new StringItem(newbest ? "New Best:\n" : "Current:\n",
            currPushes + " pushes\n" + currMoves + " moves"));

        scoreForm.append(new StringItem(newbest ? "Old Best:\n" : "Best:\n",
            bestPushes + " pushes\n" + bestMoves + " moves"));

        String title = "Scores";

        if (newbest) {
            title = "Congratulations";
        }

        scoreForm.setTitle(title);

        return scoreForm;
    }

    /**
     * Handle a repeated arrow keys as though it were another press.
     *
     * @param keyCode the key pressed.
     */
    protected void keyRepeated(int keyCode) {
        int action = getGameAction(keyCode);
        switch (action) {
        case Canvas.LEFT:
        case Canvas.RIGHT:
        case Canvas.UP:
        case Canvas.DOWN:
            keyPressed(keyCode);
            break;
        default:
            break;
        }
    }

    /**
     * Handle a single key event.
     * The LEFT, RIGHT, UP, and DOWN keys are used to
     * move the pusher within the Board.
     * Other keys are ignored and have no effect.
     * Repaint the screen on every action key.
     */
    protected void keyPressed(int keyCode) {

        // Protect the data from changing during painting.
        synchronized (board) {
            cancelTo();

            int action = getGameAction(keyCode);
            int move;

            switch (action) {
            case Canvas.LEFT:
                move = Board.LEFT;

                break;

            case Canvas.RIGHT:
                move = Board.RIGHT;

                break;

            case Canvas.DOWN:
                move = Board.DOWN;

                break;

            case Canvas.UP:
                move = Board.UP;

                break;

                // case 0: // Ignore keycode that don't map to actions.
            default:
                return;
            }

            // Tell the board to move the piece
            int stored = board.getStored();
            int dir = board.move(move);

            if (stored < board.getStored()) {
                // Play a note if a packet hit the spot.
                play(storedTune);
            }

            int pos = board.getPusherLocation();
            updateTilesNear(pos, dir);
            updateSprite(dir);
        } // End of synchronization on the Board.
    }

    /**
     * Update the scores for the current level if it has
     * been solved and the scores are better than before.
     */
    private void updateScores() {
        if (!solved) {
            return;
        }

        int sp = score.getPushes();
        int bp = board.getPushes();
        int bm = board.getMoves();

        /*
         * Update the scores.  If the score for this level is lower
         * than the last recorded score save the lower scores.
         */
        if ((sp == 0) || (bp < sp)) {
            score.setLevelScore(bp, bm);
        }
    }

    /** Cancel the animation. */
    private void cancelTo() {
        targetx = -1;
        targety = -1;
    }

    /**
     * Called when the pointer is pressed.
     * Record the target for the pusher.
     *
     * @param x location in the Canvas
     * @param y location in the Canvas
     */
    protected void pointerPressed(int x, int y) {
        targetx = (x - tiles.getX()) / cell;
        targety = (y - tiles.getY()) / cell;
    }

    /**
     * Add a listener to notify when the level is solved.
     * The listener is send a List.SELECT_COMMAND when the
     * level is solved.
     *
     * @param l the object implementing interface CommandListener
     */
    public void setCommandListener(CommandListener l) {
        super.setCommandListener(l);
        listener = l;
    }

    /**
     * Update the Sprite location from the board supplied position
     *
     * @param dir the sprite is moving
     */
    private void updateSprite(int dir) {
        int loc = board.getPusherLocation();
        int x = (loc & 0x7fff) * cell;
        int y = ((loc >> 16) & 0x7fff) * cell;
        // Update sprite location
        sprite.setPosition(tiles.getX() + x, tiles.getY() + y);
        dir = Board.RIGHT; // Graphics.drawRegion doesn't do xofrm

        switch (dir & 0x03) {
        case Board.LEFT:
            sprite.setTransform(Sprite.TRANS_ROT180);

            break;

        case Board.UP:
            sprite.setTransform(Sprite.TRANS_ROT90);

            break;

        case Board.DOWN:
            sprite.setTransform(Sprite.TRANS_ROT270);

            break;

        default:
            sprite.setTransform(Sprite.TRANS_NONE);

            break;
        }
    }

    /**
     * Queue a repaint for an area around the specified location.
     *
     * @param loc an encoded location from Board.getPusherLocation
     * @param dir that the pusher moved and flag if it pushed a packet
     */
    void updateTilesNear(int loc, int dir) {
        int x = loc & 0x7fff;
        int y = (loc >> 16) & 0x7fff;

        // Update cells if any were moved
        if ((dir >= 0) && ((dir & Board.MOVEPACKET) != 0)) {
            updateTile(x, y);
            updateTile(x + 1, y);
            updateTile(x - 1, y);
            updateTile(x, y + 1);
            updateTile(x, y - 1);
        }
    }

    /**
     * Paint the contents of the Canvas.
     * The clip rectangle of the canvas is retrieved and used
     * to determine which cells of the board should be repainted.
     *
     * @param g Graphics context to paint to.
     */
    public void paint(Graphics g) {
        flushGraphics();
    }

    /**
     * The canvas is being displayed.
     * Stop the event handling and animation thread.
     */
    protected void showNotify() {
        thread = new Thread(this);
        thread.start();
    }

    /**
     * The canvas is being removed from the screen.
     * Stop the event handling and animation thread.
     */
    protected void hideNotify() {
        thread = null;
    }

    /**
     * The main event processor. Events are polled and
     * actions taken based on the directional events.
     */
    public void run() {
        Graphics g = getGraphics(); // Of the buffered screen image
        Thread mythread = Thread.currentThread();

        // Loop handling events
        while (mythread == thread) {
            try { // Start of exception handler

                boolean newlySolved = false;

                if (!solved && board.solved()) {
                    newlySolved = solved = true;
                    play(solvedTune);
                }

                if (newlySolved && (listener != null)) {
                    listener.commandAction(List.SELECT_COMMAND, this);
                }

                if ((targetx >= 0) && (targety >= 0)) {
                    int dir = board.runTo(targetx, targety, 1);
                    int pos = board.getPusherLocation();

                    if (dir < 0) {
                        targetx = targety = -1; // Cancel target
                    } else {
                        updateTilesNear(pos, dir);
                        updateSprite(dir);
                    }
                }

                // Check that the pusher is not to close to the edge
                int loc = board.getPusherLocation();
                int x = (loc & 0x7fff) * cell;
                int y = ((loc >> 16) & 0x7fff) * cell;

                int lx = tiles.getX();
                int ly = tiles.getY();

                int panScale = cell / 4;

                if (panScale < 1) {
                    panScale = 1;
                }

                // If the sprite is too near the edge (or off) pan
                if ((lx + x) > (width - cell - cell)) {
                    tiles.move(-panScale, 0);
                    sprite.move(-panScale, 0);
                }

                if ((lx + x) < cell) {
                    tiles.move(panScale, 0);
                    sprite.move(panScale, 0);
                }

                if ((ly + y) > (height - cell - cell)) {
                    tiles.move(0, -panScale);
                    sprite.move(0, -panScale);
                }

                if ((ly + y) < cell) {
                    tiles.move(0, panScale);
                    sprite.move(0, panScale);
                }

                // Draw all the layers and flush
                layers.paint(g, 0, 0);

                if (mythread == thread) {
                    flushGraphics();
                }

                // g.drawString("PushPuzzle Level " + level, 0, height,
                //			     Graphics.BOTTOM|Graphics.LEFT);
                try {
                    mythread.sleep(PanRate);
                } catch (java.lang.InterruptedException e) {
                    // Ignore
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    /** Play the simple tune supplied. */
    void play(byte[] tune) {
        try {
            if (tonePlayer == null) {
                // First time open the tonePlayer
                tonePlayer = Manager.createPlayer(Manager.TONE_DEVICE_LOCATOR);
                tonePlayer.realize();
                toneControl = (ToneControl) tonePlayer.getControl(
                    "javax.microedition.media.control.ToneControl");
            }

            tonePlayer.deallocate();
            toneControl.setSequence(tune);
            tonePlayer.start();
        } catch (Exception ex) {
            System.out.println(ex.getMessage());
        }
    }

    /*
     * Close the tune player and release resources.
     */
    void closePlayer() {
        if (tonePlayer != null) {
            toneControl = null;
            tonePlayer.close();
            tonePlayer = null;
        }
    }
}