maincanvas.java

J2ME手机游戏50例

package demo;
import java.util.Random;

import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.GameCanvas;

public class MainCanvas extends GameCanvas implements Runnable{
	public static final int GAME_UI		= 0;	//进入用户界面
	public static final int GAME_GAMING	= 1;	//进行游戏
	public static final int GAME_END		= 2;	//游戏结束
	public static final int GAME_STATE_NUM = 3;	//状态总数
	private int m_nState	= GAME_UI;			//存储当前的游戏状态
	
	private boolean		m_bRunning;			//控制线程运行
	private MyUI			m_UI;				//用户界面	
	private Garage			m_aGarage[][];		//车库对象数组
	private int			m_nCurRow = 0;		//当前选择的行
	private int			m_nCurCol = 0;		//当前选择的列
	private int			m_nLastRow = -1;	//上次选择的行
	private int			m_nLastCol = -1;	//上次选择的列
	private Image			m_CarImg;			//汽车图像
	private int			m_nTime;			//游戏时间
	private Random			m_Random;
	public MainCanvas(){
		super(true);
		m_Random = new Random();
		m_UI = new MyUI();
		try{
			//读取车库图像与汽车图像
			Image imgGarage = Image.createImage("/demo/garage.png");
			m_CarImg = Image.createImage("/demo/car.png");
			//创建车库，并设置车库位置
			m_aGarage = new Garage[3][4];
			int x, y;
			y = getHeight()/2 - imgGarage.getHeight() - imgGarage.getHeight()/2;
			for( int row = 0; row < m_aGarage.length; row ++ ){
				x = getWidth()/2 - imgGarage.getWidth()*2;
				for( int col = 0; col < m_aGarage[0].length; col ++ ){
					m_aGarage[row][col] = new Garage(imgGarage, x, y);
					x = x + imgGarage.getWidth();
				}
				y = y + imgGarage.getHeight();
			}
		}
		catch (Exception ex){} 
		setState(GAME_UI);						//设置游戏状态
		ResetCars();							//设置车库中的汽车
		Start();								//启动线程
	}
	private void ResetCars(){					//设置车库中的汽车
		//先将车库中的汽车清空
		for( int row = 0; row < m_aGarage.length; row ++ ){
			for( int col = 0; col < m_aGarage[0].length; col ++ ){
				m_aGarage[row][col].setState(Garage.GARAGE_CLOSE);
				m_aGarage[row][col].setCar(null, 0, 0, 0);
			}
		}
		//将六种类型的汽车随机设置到12个车库中
		for( int type = 0; type < 6; type ++ ){
			//随机设置汽车
			int num = Math.abs(m_Random.nextInt() % 12);
			int row = num / 4;
			int col = num % 4;
			while( m_aGarage[row][col].getCarType() != -1 ){
				//如果车库中已有汽车,则用加1的办法取下一个车库
				num ++;
				if( num >= 12 )
					num = 0;
				row = num / 4;
				col = num % 4;
			}
			m_aGarage[row][col].setCar(m_CarImg, type, 29, 21);
			
			//同一类型的汽车,需要设置到两个车库中
			num = Math.abs(m_Random.nextInt() % 12);
			row = num / 4;
			col = num % 4;
			while( m_aGarage[row][col].getCarType() != -1 ){
				num ++;
				if( num >= 12 )
					num = 0;
				row = num / 4;
				col = num % 4;
			}
			m_aGarage[row][col].setCar(m_CarImg, type, 29, 21);
		}
		m_nTime = 600;
	}
	private void setState( int state ){		//设置当前的游戏状态
		if( state < 0 || state >= GAME_STATE_NUM )
			return;
		m_nState = state;
	}
	public void Start(){
		m_bRunning = true;
		Thread thread = new Thread(this);		//分配新线程
		thread.start();							//线程启动
	}
	public void run() {						//新线程自动调用此方法
		//获取系统当前时间，并将时间换算成以毫秒为单位的数
		long T1 = System.currentTimeMillis();
		long T2 = T1;
		while(m_bRunning){
			T2 = System.currentTimeMillis();
			if( T2 - T1 > 100 ){			    //间隔100毫秒
				T1 = T2;
				Input();
				Logic();
				Paint();
			}
		}
	}
	public void Stop(){						//终止游戏
		m_bRunning = false;
	}
	public void Input(){
		int keyStates = getKeyStates();
		switch( m_nState ){
		case GAME_UI:
			m_UI.Input( keyStates );
			if( m_UI.getState() == MyUI.UI_HIDE )
				setState(GAME_GAMING);			//设置游戏状态
			break;
		case GAME_GAMING:
			if( ( keyStates & GameCanvas.FIRE_PRESSED ) != 0 ){
				
				if( m_aGarage[m_nCurRow][m_nCurCol].getState() == Garage.GARAGE_CLOSE )
				{//如果当前选择的车库门是关着的
					if( m_nLastRow < 0 )
					{//如果上次没有选择车库
						m_nLastRow = m_nCurRow;
						m_nLastCol = m_nCurCol;
						m_aGarage[m_nCurRow][m_nCurCol].setState(Garage.GARAGE_OPEN);
					}
					else 
					{//如果上次选择了一个车库
						if( m_aGarage[m_nCurRow][m_nCurCol].getCarType() == 
							m_aGarage[m_nLastRow][m_nLastCol].getCarType() )
						{//如果本次选择与上次选择的车库中的汽车类型相同,则设置车库永久打开
							m_aGarage[m_nCurRow][m_nCurCol].setState(Garage.GARAGE_OPEN_EVER);
							m_aGarage[m_nLastRow][m_nLastCol].setState(Garage.GARAGE_OPEN_EVER);
							if( isAllOpen() )	//车库门是否全部永久打开了
								setState(GAME_END);
						}
						else
						{//如果本次选择与上次选择的车库中的汽车类型不同,则关闭车库门
							m_aGarage[m_nCurRow][m_nCurCol].setState(Garage.GARAGE_CLOSING);
							m_aGarage[m_nLastRow][m_nLastCol].setState(Garage.GARAGE_CLOSING);
						}
						m_nLastRow = -1;
						m_nLastCol = -1;
					}
				}
			}
			//移动当前的选择
			else if( ( keyStates & GameCanvas.LEFT_PRESSED ) != 0 )
				m_nCurCol --;
			else if( ( keyStates & GameCanvas.RIGHT_PRESSED ) != 0 )
				m_nCurCol ++;
			else if( ( keyStates & GameCanvas.UP_PRESSED ) != 0 )
				m_nCurRow --;
			else if( ( keyStates & GameCanvas.DOWN_PRESSED ) != 0 )
				m_nCurRow ++;
			//矫正当前的选择值
			if( m_nCurRow < 0 )
				m_nCurRow = 0;
			if( m_nCurRow >= m_aGarage.length )
				m_nCurRow = m_aGarage.length - 1;
			if( m_nCurCol < 0 )
				m_nCurCol = 0;
			if( m_nCurCol >= m_aGarage[0].length )
				m_nCurCol = m_aGarage[0].length - 1;

			break;
		case GAME_END:
			if( ( keyStates & GameCanvas.FIRE_PRESSED ) != 0 ){
				ResetCars();
				setState(GAME_GAMING);
			}
		}
	}
	//判断车库门是否全部永久打开,返回true表示全部永久打开,false则没有全部永久打开
	private boolean isAllOpen(){				
		for( int row = 0; row < m_aGarage.length; row ++ ){
			for( int col = 0; col < m_aGarage[0].length; col ++ ){
				if( m_aGarage[row][col].getState() != Garage.GARAGE_OPEN_EVER ){
					return false;
				}
			}
		}
		return true;
	}
	public void Logic(){
		switch( m_nState ){
		case GAME_UI:
			break;
		case GAME_GAMING:
			//汽车逻辑操作
			for( int row = 0; row < m_aGarage.length; row ++ ){
				for( int col = 0; col < m_aGarage[0].length; col ++ ){
					m_aGarage[row][col].Logic();
				}
			}
			m_nTime --;
			if( m_nTime <= 0 )					//如果游戏超时
				setState(GAME_END);
			break;
		case GAME_END:
			break;
		}
	}
	public void Paint(){
		Graphics g = getGraphics();
		//用黑色清屏
		g.setColor(0);
		g.fillRect(0, 0, getWidth(), getHeight());
	
		g.setColor(0xFFFFFFFF);
		switch( m_nState ){
		case GAME_UI:							//显示标题界面
			m_UI.Paint(g, getWidth(), getHeight());
			break;
		case GAME_GAMING:						//显示游戏画面
			for( int row = 0; row < m_aGarage.length; row ++ ){
				for( int col = 0; col < m_aGarage[0].length; col ++ ){
					m_aGarage[row][col].Paint(g);
					if( row == m_nCurRow && col == m_nCurCol )
					{//在当前选择的车库位置画方框						
						g.drawRect(m_aGarage[row][col].getX(),
								m_aGarage[row][col].getY(),
								m_aGarage[row][col].getWidth(),
								m_aGarage[row][col].getHeight() );
					}
				}
			}
			//显示文字信息
			StringBuffer strText = new StringBuffer();
			strText.append("Time:");
			strText.append(m_nTime / 10);
			g.drawString( strText.toString(), 5, 5, 0 );
			break;
		case GAME_END:
			if( isAllOpen() )
				g.drawString( "恭喜成功", 20, getHeight()/2, 0 );
			else
				g.drawString( "继续努力", 20, getHeight()/2, 0 );
			break;
		}
		flushGraphics();
	}
}