maincanvas.java

大家看看啊!顶

import java.io.IOException;
import java.util.Random;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.GameCanvas;
import javax.microedition.lcdui.game.LayerManager;
import javax.microedition.rms.RecordStore;

public class MainCanvas extends GameCanvas implements Runnable,CommandListener{
        private Command                         ExitCommand;
        private PlaneMidlet                 midlet;
        private boolean                         m_bGameEnd = false;
        private int                                 m_nHighScore = 0;
        private int                                 m_nScore = 0;
        private MyPlane                         m_MyPlane;
        private Enemy                                 m_aEnemy[];
        private BlastSprite                m_aBlast[];
        private LayerManager                m_LayerManager;
        private Image                                m_BackImage;
        private Random                                m_Random;
        public static int                        m_nScrWidth;
        public static int                 m_nScrHeight;
        
        public MainCanvas( PlaneMidlet mMidlet )
        {
                super(true);
                midlet = mMidlet;
                ExitCommand = new Command("Exit", Command.EXIT, 0);
                addCommand(ExitCommand);
                setCommandListener(this);
                m_nScrWidth = getWidth();
                m_nScrHeight = getHeight();
                m_Random = new Random();
                m_LayerManager = new LayerManager();
                try{
                        m_BackImage = Image.createImage("/Back.png");
                        Image img = Image.createImage("/Blast.png");
                        m_aBlast = new BlastSprite[5];
                        for( int n = 0; n < m_aBlast.length; n ++ ){
                                m_aBlast[n] = new BlastSprite( img, 21, 17 );
                                m_LayerManager.append( m_aBlast[n] );
                        }
                        img = null;
                        img = Image.createImage("/MyPlane.png");
                        m_MyPlane = new MyPlane( img, 30, 20 );
                        int nX = getWidth() / 2;
                        int nY = getHeight() - 30;
                        m_MyPlane.setRefPixelPosition( nX, nY );
                        m_MyPlane.setVisible( true );
                        m_LayerManager.append( m_MyPlane );
                        m_LayerManager.append( m_MyPlane.m_Bullet );
                        img = null;
                        img = Image.createImage("/Enemy.png");
                        m_aEnemy = new Enemy[8];
                        for( int n = 0; n < m_aEnemy.length; n ++ ){
                                m_aEnemy[n] = new Enemy( img, 15, 15 );
                                m_LayerManager.append( m_aEnemy[n] );
                                m_LayerManager.append( m_aEnemy[n].m_Bullet );
                        }
                }
                catch (IOException e){}
                LoadHighScore();
                Thread thread = new Thread(this);
                thread.start();
        }
        public void Input(){
                int keyStates = getKeyStates();
                m_MyPlane.Input( keyStates );
        }
        public void Logic(){
                m_MyPlane.Logic();
                for( int n = 0; n < m_aEnemy.length; n ++ )
                        m_aEnemy[n].Logic();
                for( int n = 0; n < m_aBlast.length; n ++ )
                        m_aBlast[n].Logic();
                CreateEnemy();
                CheckCollisions();
        }
        
        protected void Paint() 
        {
                Graphics g = getGraphics();
                g.setColor(0);
                g.fillRect( 0, 0, getWidth(), getHeight() );
                if( m_BackImage != null ){
                        int nBgX = (getWidth() - m_BackImage.getWidth() )/ 2;
                        int nBgY = (getHeight() - m_BackImage.getHeight()) / 2;
                        g.drawImage( m_BackImage, nBgX, nBgY, Graphics.TOP|Graphics.LEFT );
                }
                //m_LayerManager.paint( g, 0, 0 );
                for( int n = 0; n < m_aBlast.length; n ++ ){
                        m_aBlast[n].paint( g );
                }
                for( int n = 0; n < m_aEnemy.length; n ++ ){
                        m_aEnemy[n].paint( g );
                        m_aEnemy[n].m_Bullet.paint(g);
                }
                m_MyPlane.paint(g);
                m_MyPlane.m_Bullet.paint(g);
                if( m_bGameEnd ){
                        Font mFont = g.getFont();
                        StringBuffer temp = new StringBuffer();
                        temp.append("游戏结束，本次得分：");
                        temp.append(m_nScore);
                        int nX = getWidth() / 2;
                        int nY = getHeight() / 2 - mFont.getHeight();
                        g.drawString( temp.toString(), nX, nY, Graphics.TOP|Graphics.HCENTER );
                        temp = null;
                        temp = new StringBuffer();
                        temp.append("历史最高分：");
                        temp.append(m_nHighScore);
                        nY = getHeight() / 2 + mFont.getHeight();
                        g.drawString( temp.toString(), nX, nY, Graphics.TOP|Graphics.HCENTER );
                }
                flushGraphics();
        }
        public void commandAction(Command c, Displayable s)
        {
                if (c.getCommandType() == Command.EXIT)
                {
                        midlet.notifyDestroyed();
                }
        }
        public void run() {
                long lTime1 = System.currentTimeMillis();
                long lTime2 = lTime1;
                try{
                        while(true){
                                lTime2 = System.currentTimeMillis();;
                                if( lTime2 - lTime1 > 50 ){
                                        lTime1 = lTime2;
                                        Input();
                                        Logic();
                                        Paint();
                                }
                        }
                }
                catch(Exception e){}
        }
        public void EndGame(){
                m_bGameEnd = true;
                if( m_nScore > m_nHighScore ){
                        m_nHighScore = m_nScore;
                        SaveHighScore( m_nHighScore );
                }
        }
        private void SaveHighScore( int nHighScore ){
                try
                {
                        byte b[] = new byte[4];
                        int temp = nHighScore;
                        //用一个循环将一个int型数据(4字节)，存放在b[]中
                        for (int i = b.length - 1; i >= 0; i--)
                        {
                                b[i] = new Integer(temp & 0xff).byteValue();
                            temp = temp >> 8;
                        }
                        RecordStore rs = RecordStore.openRecordStore("BattlePlane",true);
                        if( rs.getNumRecords() > 0 )
                        {                        
                                int nID = rs.getNextRecordID();
                                rs.setRecord(nID, b, 0, b.length);        
                        }
                        else
                        {
                                rs.addRecord(b,0,b.length);
                        }
                }
                catch (Exception ex)
                {
                }
        }
        private int LoadHighScore()
        {
                int nHighScore = 0;
                try
                {
                        RecordStore rs = RecordStore.openRecordStore("BattlePlane",true);
                        if ( rs.getNumRecords() > 0)
                        {
                                int nID = rs.getNextRecordID();
                                byte b[] = rs.getRecord(nID);
                                if( b != null && b.length == 4 )
                                {
                                        for (int i = 0; i < 3; i++)
                            {
                                                nHighScore += b[i];
                                if( b[i] < 0 )
                                        m_nHighScore += 256 + b[i];
                                nHighScore *= 256;
                            }

                                        nHighScore += b[3];
                            if( b[3] < 0 )
                                    nHighScore += 256;
                                }
                        }
                }
                catch (Exception ex){}
                return nHighScore;
        }
        
        private void CreateEnemy(){
                int RS = Math.abs(m_Random.nextInt() % 20);
                if( RS != 0 )
                        return;
                for( int n = 0; n < m_aEnemy.length; n ++ ){
                        if( m_aEnemy[n].isVisible() )
                                continue;
                        int nX = m_Random.nextInt();
                        nX = Math.abs( nX % ( getWidth() - 10 ) ) + 5;
                        int nSpeedX = m_Random.nextInt() % 2;
                        int nSpeedY = Math.abs( m_Random.nextInt() % 2 ) + 1;
                        m_aEnemy[n].SetSpeed( nSpeedX, nSpeedY );
                        m_aEnemy[n].setRefPixelPosition( nX, 0 );
                        m_aEnemy[n].setVisible(true);
                        return;
                }
        }
        private void CreateBlast( int nX, int nY ){
                for( int n = 0; n < m_aBlast.length; n ++ ){
                        if( m_aBlast[n].isVisible() )
                                continue;
                        m_aBlast[n].setRefPixelPosition( nX, nY );
                        m_aBlast[n].setFrame(0);
                        m_aBlast[n].setVisible(true);
                        return;
                }
                m_aBlast[0].setRefPixelPosition( nX, nY );
                m_aBlast[0].setFrame(0);
                m_aBlast[0].setVisible(true);
        }
        private void CheckCollisions(){
                for( int n = 0; n < m_aEnemy.length; n ++ ){
                        //我方飞机与敌人炮弹碰撞
                        if( m_MyPlane.collidesWith( m_aEnemy[n].m_Bullet, true ) ){
                                CreateBlast( m_MyPlane.getRefPixelX(), 
                                                m_MyPlane.getRefPixelY() );
                                m_aEnemy[n].m_Bullet.setVisible(false);
                                EndGame();
                                return;
                        }
                        //我方炮弹与敌人碰撞
                        if( m_MyPlane.m_Bullet.collidesWith( m_aEnemy[n], true ) ){
                                CreateBlast( m_aEnemy[n].getRefPixelX(), 
                                                m_aEnemy[n].getRefPixelY() );
                                m_nScore ++;
                                m_aEnemy[n].setVisible(false);
                                m_MyPlane.m_Bullet.setVisible(false);
                                
                        }
                }
        }
}