malicanvas.java

一个Java小程序

/**
 * @(#)MaliCanvas.java	
 * Copyright (c) 2004-2005 wuhua of workroom Inc. All Rights Reserved.
 * @version 	1.0, 10/05/2004
 * @author 	饶荣庆
 * @author 	余煜辉
 */
package com.wuhua.mali;

import java.util.Timer;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Font;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.game.GameCanvas;

public class MaliCanvas extends GameCanvas implements CommandListener
{
	//---------------------------------------------------------
	//属性字段
	/**
	 *定义一个屏幕对象用于显示游戏窗体
	 */
	public Display display;

	/**
	 *游戏菜单类
	 */
	public WelcomeToGame welcomeToGame;

	/**
	 *玛莉类
	 */
	public Mali mali = null;

	/**
	 *游戏线程类
	 */
	public GameThread game;

	/**
	 *栏杆类
	 */
	public Parapet parapet = null;

	/**
	 *A Timer
     */
	private Timer timer;
    private MillisecondTask mt;
	
	/**
	 *启动与暂停变量,来控制时间
	 */
	public static boolean isStart;
	private	static boolean isPause;

	/**
	 *定义游戏3个软键用来控制游戏
	 */
	private Command goCommand = null;
	private Command pauseCommand = null;
	private Command stopCommand = null;
	private Command backCommand = null;

	/**
	 *定义屏幕宽度变量
	 */
	public  int DISP_WIDTH = getWidth();

	/**
	 *定义屏幕高度变量
	 */
	public  int DISP_HEIGHT = getHeight();

	/**
	 *画布的水平位置
	 */
	public static int CANVAS_X;

	/**
	 *画布的垂直位置
	 */
	public static int CANVAS_Y;

	/**
	 *定义图象玛莉前进贴的顺序
	 */
	private int order;

	/**
	 *定义玛莉跳跃贴的顺序
	 */
	private int jumpOrder = 1;

	/**
	 *定义判断玛莉是否跳过
	 */
	private boolean isJump;

	/**
	 *玛莉跑的路程
	 */
	private int distance;

	/*时间格式字符串*/
	private String theTime;

    //----------------------------------------------------------
    //   初始化

    /**
    * standard constructor.
    */
	public MaliCanvas()
	{
		super(true);
		try
		{
			this.mali = new Mali(10, (DISP_HEIGHT/4) * 3 - 24);
		}
		catch(Exception e)
		{}
		
		try
		{
			this.parapet = new Parapet(DISP_WIDTH - 10,	(DISP_HEIGHT/4) * 3);
		}
		catch(Exception e)
		{
		}
		/*用来计算玛莉赛跑用掉的时间*/
		this.timer = new Timer();
		this.mt = new MillisecondTask();
		
		/*初始化时间格式*/
		this.theTime = "00:00";


		this.game= new GameThread(this);
		this.drawScreen(this.getGraphics());  //初始化游戏界面
		this.goCommand = new Command("Go", Command.OK, 2);
		this.pauseCommand = new Command("Pause", Command.OK, 2);
		this.stopCommand = new Command("Stop", Command.OK, 2);
		this.backCommand = new Command("Back", Command.BACK, 2);
		this.addCommand(goCommand);
		this.addCommand(backCommand);
		this.setCommandListener(this);
		//this.maliManager = new MaliManager(0,0, DISP_WIDTH,  DISP_HEIGHT);
	}
	
	//----------------------------------------------------------
    //   方法
	public void showForm(Display display, WelcomeToGame welcomeToGame)// GameMenu gameMenu)  //显示窗体
	{			
		this.welcomeToGame = welcomeToGame;
	   	this.display = display;
		this.display.setCurrent(this);
	}

	/**
	 *返回图形给线程用的方法
	 */
	public Graphics getGraph()
	{
		return this.getGraphics();
	}

	/**
	 *处理用户按件游戏事件的方法
	 */
	public void input()
	{	
		/*获得按键代号*/
		int keyStates = getKeyStates();
        // Left
        if ((keyStates & RIGHT_PRESSED) != 0)
		{	
			
			this.down();
			this.maliAction();
			this.parapetAction();	
			//this.checkCollision();
			 
        }
        // Right
        if ((keyStates & LEFT_PRESSED) !=0 )
		{
			this.maliLeftDecelerate(); //减速
        }
        // Up
        if ((keyStates & UP_PRESSED) != 0) 
		{
			this.jump();			
        }

		if (this.distance == 110)  //等于110米游戏结束
		{
			this.game.requestStop();	 //停止游戏
			this.removeCommand(pauseCommand);
			this.addCommand(goCommand);
		}
	}

    /**
	 *用来描述玛莉的运动状态
	 */
	public void maliAction()
	{
		mali.setFrame(order);
		/*检查有没有跟栏杆碰撞*/
		//if (this.parapet.getRefPixelX() > DISP_WIDTH/3)
		//{
			this.checkCollision();
		//}
		/*玛莉加速到一定位置时保持哪个位置*/
		if (mali.getRefPixelX() < DISP_WIDTH/3)		  
		{		  
			mali.advance();	
		}
       	
		if (game.delay > 30)
		{
			game.delay = game.delay - 3; //延迟减少来显示加速
		}

		/*假如栏杆出了屏幕则创建一个新的，并显示出来*/
		if (parapet.getRefPixelX() < 0)	  
		{
			/*假如一个栏杆消失了则玛莉跑的路程加10*/
			this.distance = this.distance + 10;
			try
			{
				this.parapet = new Parapet(DISP_WIDTH, (DISP_HEIGHT/4) * 3);
			}
			catch(Exception e)
			{
			}
			/*当一个栏杆消失后，玛莉的速度加快，为了保持玛莉与栏杆的相对速度，所以栏杆的速度加快*/
			this.parapetAction();	//保持玛莉与栏杆的相对运动
		}
		
		order++;   //动画的贴号
		if (order>3)
		{
			order=0;
		}
	}

	/**
    *栏杆的移动速度方法
	*/
	public void parapetAction()
	{
		this.parapet.advance();
		this.parapet.accelerate(); //加速
	}

	/**
	 *玛莉遇到障碍时减速
	 */
	public void maliDecelerate()
	{
		this.game.delay = 60;	 //用延迟来显示玛莉减速
		this.parapet.advance();	
		this.parapet.decelerate(); //减速
	}

	/**
	 *按向左键时候玛莉减速
	 */
	public void maliLeftDecelerate()
	{
		mali.setFrame(order);
	
		if (game.delay < 80)
		{
			game.delay = game.delay + 5; //延迟减少来显示加速
		}
			 order++;   //动画的贴号
		
		if (order >= 3)
		{
			order = 2;	 //玛莉停下来的时候固定的贴号
		}

		this.parapet.advance(); //栏杆前进	
		this.parapet.decelerate(); //减速
	}

	/**
	 *在画布里实现玛莉跳跃的方法
	 */
	public void jump()
	{	
		if (!isJump)
		{	
			this.mali.setFrame(0);
			this.parapetAction(); //给栏杆运动使玛莉产生跳跃的效果	
			this.mali.jump();		    
		}
		
		isJump = true;
		this.checkCollision();
	}

	/**
	 *在画布实现玛莉下降的方法
	 */
	public void down()
	{
		if (isJump)
		{	 
			this.parapetAction(); //给栏杆运动产生跳跃的效果
			this.parapetAction();
			/*用来延迟运行*/
			for (int i = 0; i < 5001; i++ )
			{
				if (i == 5000 && isJump)
				{
					
					this.mali.down();
					this.isJump = false;
				}
			}
		}
		
	}
	
	/**
	 *碰撞算法
	 */
	public void checkCollision() 
	{
		if (this.isJump == true)
		{
		}
		else if (this.parapet.getRefPixelX() > DISP_WIDTH/3 && this.isJump == false )
		{
			if(this.mali.checkCollision(this.parapet)) 
			{
				this.maliDecelerate();//玛莉减速
				this.parapet.setFrame(1); //假如被玛莉碰到，则栏杆倒下
			}
		}
		/*if (this.)
		{
		}*/
	}

	/*实现记时器的方法*/
	public void clock()
	{
		timer.schedule(mt, 1, 1);   //锁定时间进度为0.001秒，并放置这个时间隔要运行的程序。
	}

	/**
	 *格式化时间的方法
	 */
	public void formatTime(int l)
	{
		int sec = l / 60;
		int millisec = l % 60;

		if (sec < 10)
		{
			theTime = "0" + sec + ":";
		}
		else
		{
			theTime = sec + ":";
		}

		if (millisec < 10)
		{
			theTime = theTime + "0" + millisec ;
		}
		else
		{
			theTime = theTime + millisec ;
		}
	}



   /**
    *此方法是用来画出玛莉与栏杆
	*/
	public void drawScreen(Graphics g) 
	{	
		/*背景颜色*/
	 //   g.setColor(255, 255,255); // black
        g.fillRect(0, 0, DISP_WIDTH, DISP_HEIGHT ); 

		g.setColor(0);
		g.drawString("Time:", DISP_WIDTH/2, 50, Graphics.LEFT | Graphics.TOP); 
		g.drawString("Distance: "  +  "       meter", DISP_WIDTH/2 - 100, 50, Graphics.LEFT | Graphics.TOP);
		/*显示时间与路程*/
		this.formatTime(mt.getTime());
		g.setColor(255);
		g.drawString("         " + theTime, DISP_WIDTH/2, 50, Graphics.LEFT | Graphics.TOP); 
		g.drawString("                " + distance , DISP_WIDTH/2 - 100, 50, Graphics.LEFT | Graphics.TOP); 

		/*跑道的颜色*/
		g.setColor(21, 100, 100);
        g.fillRect(0, (DISP_HEIGHT/4) * 3 + 25, DISP_WIDTH, DISP_HEIGHT);

		/*绘制玛莉与栏杆*/
		this.mali.paint(g);
		this.parapet.paint(g);

		if (game.isStop())
		{
			g.setColor(255, 0, 0);
			g.setFont(Font.getFont(0, 1, 16));
			g.drawString("GAME OVER",  DISP_WIDTH/2 - 50, DISP_HEIGHT/2, Graphics.LEFT | Graphics.TOP); 
		}

		/*刷新屏幕*/
		flushGraphics();
	}


	public void commandAction(Command c,Displayable s)
	{	
		if(c == goCommand)
		{
			/*启动开始记时*/
			this.isStart = true;
			this.removeCommand(goCommand);
		    this.addCommand(pauseCommand);
			this.game.go(); //启动游戏
			//GameThread.myAlreadyStarted = true;
		}

		if (c == pauseCommand)
		{
			/*暂停停止记时*/
			this.isStart = false;
			this.removeCommand(pauseCommand);
		    this.addCommand(goCommand);
			game.pause();
		}

		if (c == backCommand)
		{
			/*返回游戏欢迎界面*/
			 this.display.setCurrent(welcomeToGame);
		}
	}
	
}