screen.java

J2ME做的打砖块游戏,是学校的课程项目

import javax.microedition.lcdui.*;
import javax.microedition.midlet.MIDlet;
import java.lang.System;

public class Screen extends Canvas {
    private Font fontSmall;
    private Font fontMedium;
    private Font fontLarge;
    private Font font;
    public static int width;
    public static int height;
    private static final int TL_ANCHOR = Graphics.TOP | Graphics.LEFT;
    private static final int TH_ANCHOR = Graphics.TOP | Graphics.HCENTER;
    private Image buf;
	public Image brick_1;
	public Image brick_2;
	public Image paddle_1;
	public Image background;
	
    public static Graphics GRAPHICS;
    public static final int BACKGROUND = ThreeDColor.white.getRGB();
    private int lastState;
    private int lastScore;
    private int lastLives;
    private Engine engine;
    private EngineState state;
	public static int fontHeight;
    private MIDlet midlet;

    public Screen(MIDlet midlet) {
        width = getWidth();
        height = getHeight();

        fontSmall = Font.getFont(Font.FACE_SYSTEM, Font.STYLE_PLAIN, 
                Font.SIZE_SMALL);
        fontMedium = Font.getFont(Font.FACE_SYSTEM, Font.STYLE_PLAIN, 
                Font.SIZE_MEDIUM);
        fontLarge = Font.getFont(Font.FACE_SYSTEM, Font.STYLE_PLAIN, 
                Font.SIZE_LARGE);
        
        font = height < 150 ? fontSmall : fontMedium;
        fontHeight = font.getHeight();
		try{
			brick_1 = Image.createImage("/j8.png");
			brick_2 = Image.createImage("/j9.png");
			paddle_1= Image.createImage("/j6.png");
			background = Image.createImage("/background.png");
			background = scale(background, width, height);
		}
		catch(Exception ex)
		{
		}
        buf = Image.createImage(width, height - (fontHeight + 5));
        GRAPHICS = buf.getGraphics();
        state = new EngineState();

        lastState = -1;
        lastScore = -1;
        lastLives = -1;
        
        this.midlet = midlet;
    }

	public Image scale(Image src, int width, int height)
	{
		long start = System.currentTimeMillis();
		int scanline = src.getWidth();
		int srcw = src.getWidth();
		int srch = src.getHeight();
		int buf[] = new int[srcw*srch];
		src.getRGB(buf, 0, scanline, 0, 0, srcw, srch);
		int buf2[] = new int[width*height];
		for (int y = 0; y < height; y++)
		{
			int c1 = y * width;
			int c2 = (y * srch / height) * scanline;
			for (int x = 0; x < width; x++)
			{
				buf2[c1 + x] = buf[c2 + x * srcw / width];
			}
		}
		Image img = Image.createRGBImage(buf2, width, height, true);
		long end = System.currentTimeMillis();
		return img;
	}

    public void setEngine(Engine engine) {
        this.engine = engine;
        engine.getState(state);
        state.menu.setMIDlet(midlet);
    }
    
    public void keyPressed(int keycode) {
        if (state.state == Engine.MENU) {
            engine.setLastKeyPressed(System.currentTimeMillis());
            state.menu.keyPressed(getGameAction(keycode));
        } else {
            engine.keyPressed(keycode, getGameAction(keycode));
        }
    }
    
    public void keyReleased(int keycode) {
        if (state.state != Engine.MENU) {
            engine.keyReleased(keycode, getGameAction(keycode));
        }
    }
    
    private void paintBackground(Graphics g) {
        g.setColor(BACKGROUND);
        g.fillRect(0, 0, width, height);
    }

    private void paintTitle(Graphics g) {
        engine.getState(state);

        if (lastState != Engine.TITLE) {
            paintBackground(GRAPHICS);
            
        } 
        g.drawImage(buf, 0, 0, TL_ANCHOR);
        g.setColor(BACKGROUND);
        g.fillRect(0, 0, width, height);
		g.drawImage(background, 0, 0, g.TOP | g.LEFT);
        g.setFont(fontLarge);
        g.setColor(ThreeDColor.red.getRGB());
        g.drawString("Bricks", width / 2, height / 2, TH_ANCHOR);
    }

    private void paintOver(Graphics g) {        
        paintBackground(g);

        g.setFont(fontLarge);

        g.setColor(ThreeDColor.red.getRGB());
        g.drawString("Game", width / 2, height / 2 - 10, TH_ANCHOR);
        g.drawString("Over", width / 2, height / 2 + 10, TH_ANCHOR);
		if (Engine.internetRank.length() == 0)
		{
			g.drawString("CANNOT UPLOAD SCORE", width / 2, height / 2 + 30, TH_ANCHOR);
		}
		else
		{
			g.drawString(Engine.internetRank, width / 2, height / 2 + 30, TH_ANCHOR);
		}
		//for (int i= 0; i < 100000; i++);

    }

	public void paintMenu(Graphics g)
	{
        engine.getState(state);
        
        if (lastState != Engine.MENU) {
            paintBackground(GRAPHICS);
        } 
        
        g.drawImage(buf, 0, 0, TL_ANCHOR);
        g.setColor(BACKGROUND);
        g.fillRect(0, 0, width, height);       
        
        g.setFont(fontLarge);

        g.setColor(ThreeDColor.black.getRGB());
		g.drawImage(background, 0, 0, g.TOP | g.LEFT);
        for (int i = 0; i < state.menu.getItems().length; i++) {
            if (state.menu.getItems()[i].isEnabled()) {
                g.setColor(ThreeDColor.purple.getRGB());
            } else {
                g.setColor(ThreeDColor.gray.getRGB());
            }
            g.drawString(state.menu.getItems()[i].getText(), width / 2, 
                    height / 3 + 30 + 20 * i, TH_ANCHOR);
        }
        
        g.setColor(ThreeDColor.pink.getRGB());
        
        g.drawString(state.menu.getItems()[state.menu.getSelected()].getText(), 
                width / 2, height / 3 + 30 + 20 * state.menu.getSelected(), 
                TH_ANCHOR);
    }

	public void paintProgress(Graphics g)
	{
		engine.getState(state);
    if(state.currentNum==0)
    {
			g.drawImage(buf, 0, 0, TL_ANCHOR);
			g.setColor(BACKGROUND);
			g.fillRect(0, 0, width, height);
  	}

		if ( state.currentNum >  state.totalNum)
			state.currentNum = state.totalNum;
		int barWidth = 80, barHeight = 15;
		g.setColor(ThreeDColor.blue.getRGB());
		g.drawString("Loading......", (width - 40) / 2, height * 2 / 5 - 35, TH_ANCHOR);
		g.drawRect((width - 60) / 2, height * 2 / 5, barWidth, barHeight);
		g.setColor(ThreeDColor.blue.getRGB());
		g.fillRect((width - 60) / 2, height * 2 / 5, state.currentNum*4, barHeight);


	}

	public void paintHelp(Graphics g)
	{
		engine.getState(state);
		paintBackground(g);
		g.setFont(fontLarge);
		g.setColor(ThreeDColor.black.getRGB());
		g.drawString("This game provides three level files", 0, 0, TL_ANCHOR);
		g.drawString("which are loaded locally, you can also", 0, fontHeight, TL_ANCHOR);
		g.drawString("download level from internet by pressi", 0, 2*fontHeight, TL_ANCHOR);
		g.drawString("ng Download Level in the Menu. You", 0, 3 * fontHeight, TL_ANCHOR);
		g.drawString("have three lives, your score will be", 0, 4 * fontHeight, TL_ANCHOR);
		g.drawString("upload to server after game is over", 0, 5 * fontHeight, TL_ANCHOR);
	}

	public void paintNonetwork(Graphics g)
	{
		engine.getState(state);
		paintBackground(g);
		g.setFont(fontLarge);
		g.setColor(ThreeDColor.black.getRGB());
		g.drawString("No Network Connection", width / 2, height / 2 + 10, TH_ANCHOR);

	}


    public void paint(Graphics g) {
        engine.getState(state);
        g.setFont(font);
        
        if (state.state == Engine.TITLE) {
            paintTitle(g);
        } else if (state.state == Engine.MENU) {
            paintMenu(g);
        } else if (state.state == Engine.OVER) {
            paintOver(g);
            state.menu.resetSelected();
            state.menu.showResumeItem(false);
		}
		else if (state.state == Engine.PROGRESS)
		{
			paintProgress(g);

		}
		else if (state.state == Engine.HELP)
		{
			paintHelp(g);
		}
		else if (state.state == Engine.NONETWORK)
		{
			paintNonetwork(g);

		}
		else
		{
			if (state.levelStarted)
			{
				paintBackground(GRAPHICS);
				g.drawImage(buf, 0, 0, TL_ANCHOR);

				if (state.state == Engine.PLAY)
				{
					g.setColor(BACKGROUND);
					g.fillRect(0, 0, width, height);

					g.setColor(ThreeDColor.black.getRGB());
					g.drawString("Score: " + state.score, width * 2 / 32,
							height - (fontHeight + 3), TL_ANCHOR);

					if (state.nextScore == -1)
						g.drawString("Next: " + "-", width * 10 / 32,
							height - (fontHeight + 3), TL_ANCHOR);
					else
						g.drawString("Next: " + state.nextScore, width * 10 / 32,
							height - (fontHeight + 3), TL_ANCHOR);
					if (state.rank == -1)
						g.drawString("Rank: " + "-", width * 16 / 32,
								height - (fontHeight + 3), TL_ANCHOR);
					else
						g.drawString("Rank: " + state.rank, width * 16 / 32,
							height - (fontHeight + 3), TL_ANCHOR);
					g.drawString("Lives: " + state.lives, width * 12 / 16,
							height - (fontHeight + 3), TL_ANCHOR);

				}
				if (state.brickCount > 0)
				{
					for (int x = 0; x < state.brickNum; x++)
					{

						if (((Brick)state.bricks[x]).pictureNum == 0)
						{
							if (state.bricks[x].strong > 0)
								state.bricks[x].paint(g, brick_1);
						}
						else if (((Brick)state.bricks[x]).pictureNum == 1)
						{
							if (state.bricks[x].strong > 0)
								state.bricks[x].paint(g, brick_2);
						}
					}
				}


				if (state.ballNumber > 0)
				{
					for (int i = 0; i < state.ballNumber; i++)
						state.ball[i].paint(g);
				}
				if (state.paddleNumber > 0)
					state.paddle.paint(g);
				if (state.capsuleNumber > 0)
				{
					for (int i = 0; i < state.capsuleNumber; i++)
					{
						if (state.capsule[i].isUsed() == false)
							state.capsule[i].paint(g);
					}
				}
			}

			lastState = state.state;
			lastScore = state.score;
			lastLives = state.lives;
		}
    }
}