maincanvas.java

J2ME编程的50个例子,适合掌上系统的编程

package demo;

import FighterMidlet;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.GameCanvas;
import javax.microedition.lcdui.game.Sprite;

public class MainCanvas extends GameCanvas 
				implements Runnable, CommandListener{
	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_BUTTON			= 2;	//游戏时显示界面按钮
	public static final int GAME_END				= 3;	//游戏结束
	public static final int GAME_STATE_NUM 		= 4;	//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;							//界面对象
	private MyBack			m_Back;							//背景对象
	private FighterSprite	m_Player;						//玩家控制的斗士对象
	private FighterSprite	m_Computer;						//电脑控制的斗士对象
	private Sprite			m_TextSp;						//图形文字对象
	private Command MenuCommand;							//高级按钮对象
	public MainCanvas( ){
		super(false);			//参数设为false，才能很好地响应keyPressed			
		try{
			//创建用户界面，并设置界面中的按钮
			MyButton button = new MyButton(41, 21, 0, 1, -1, -1, -1, 2);
			m_UI = new MyUI(button);
        }
        catch(Exception exception){}
        setState(GAME_UI);
		Start();
	}
	private void Reset(){	
		//创建斗士
		if( m_Player == null ){
			try{
				Image image = Image.createImage("/demo/man.png");
				m_Player = new FighterSprite(image, 31, 41);
				m_Computer = new FighterSprite(image, 31, 41);
			}
			catch(Exception e){}
		}	
		//让斗士们开始战斗
		m_Player.Start( 30, getHeight() - 25, true );
		m_Computer.Start( getWidth() - 30, getHeight() - 25, false );

		//创建背景
		if( m_Back == null )
			m_Back = new MyBack();
        if( MenuCommand == null ){
        	//创建菜单
        	MenuCommand = new Command("Menu", Command.OK, 0);
        	addCommand(MenuCommand);
            setCommandListener(this);
        }
        if( m_TextSp == null ){
        	//创建图形文字对象
        	try{
        		Image img = Image.createImage("/demo/text.png");
        		m_TextSp = new Sprite(img, 82, 25);
        		m_TextSp.defineReferencePixel(41, 23);
        		int x = getWidth()/2;
        		int y = getHeight()/2 - 10;
        		m_TextSp.setRefPixelPosition(x, y);
        	}
        	catch(Exception exception){}
        }
        
	}
	private void setState( int state ){					//设置游戏状态
		if( state < 0 || state >= GAME_STATE_NUM )
			return;
		m_nState = state;
		switch( m_nState ){
		case GAME_UI:										//进入用户界面
			m_UI.setState(MyUI.UI_TITLE);					//显示标题界面
			//设置本游戏的按钮类型，本游戏有:开始、退出两种按钮
			m_UI.getButton().setShow(true, false, false, false, false, true );
			break;
		case GAME_BUTTON:									//在游戏中途显示按钮
			m_UI.setState(MyUI.UI_BUTTON);
			//游戏中途，显示复位与退出按钮
			m_UI.getButton().setShow(false, true, false, false, false, true );
			break;
		case GAME_GAMING:									//正在游戏
			addCommand(MenuCommand);
			m_UI.setState(MyUI.UI_HIDE);
			break;
		case GAME_END:										//游戏结束
			m_UI.setState(MyUI.UI_HIDE);
			break;;
		}
	}
	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() {
		//得到系统当前时间,并将时间换算成毫秒
		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(){
		m_bRunning = false;
	}
	protected void keyPressed( int keyCode ){
		//继承Canvas类的方法，
		//如果响应该方法，需要在构造方法中将super的参数设置为false
		if( m_Player != null )
			m_Player.keyPressed(keyCode, getWidth());
	}
	public void Input(){
		int keyStates = getKeyStates();
		switch( m_nState ){
		case GAME_UI:
			{
				switch( m_UI.Input( keyStates ) ){
				case MyButton.BUTTON_START:					//按下开始键
					Reset();
					setState(GAME_GAMING);
					break;
				case MyButton.BUTTON_EXIT:					//按下退出键
					FighterMidlet.midlet.notifyDestroyed();
					break;
				}
			}
			break;			
		case GAME_GAMING:									//游戏中
			m_Player.Input(keyStates, getWidth());
			m_Computer.AutoInput(getWidth(), getHeight(), m_Player.getRefPixelX());
			break;
		case GAME_BUTTON:									//游戏中途显示按钮
			{
				switch( m_UI.Input( keyStates ) ){
				case MyButton.BUTTON_RESET:					//按下复位键
					Reset();
					setState(GAME_GAMING);
					break;
				case MyButton.BUTTON_EXIT:					//按下退出键
					FighterMidlet.midlet.notifyDestroyed();
					break;
				}
			}
			break;
		case GAME_END:
			break;
		}
	}
	public void Logic(){
		switch( m_nState ){		
		case GAME_GAMING:									//游戏中
			//碰撞检测
		    CheckCollision();
			m_Player.Logic(getWidth(), getHeight());
			m_Computer.Logic(getWidth(), getHeight());
			break;
		default:
			break;
		}
		
	}
	public void Paint(){
		Graphics g = getGraphics();
		//用黑色清屏
		g.setColor(0);
		g.fillRect( 0, 0, getWidth(), getHeight() );
		
		g.setColor(0xFFFF0000);
		switch( m_nState ){
		case GAME_UI:								//显示界面
			m_UI.Paint(g, getWidth(), getHeight());
			break;			
		case GAME_GAMING:							//显示游戏画面
		case GAME_BUTTON:
		case GAME_END:
			m_Back.Paint(g, getWidth(), getHeight());
			m_Player.Paint(g);
			m_Computer.Paint(g);
			//显示生命值
			StringBuffer buf = new StringBuffer();
			buf.append("Pla:");
			buf.append(m_Player.getLife());
			buf.append("   Com:");
			buf.append(m_Computer.getLife());
			g.drawString(buf.toString(), 2, 5, 0);
			if( m_nState == GAME_END )
				m_TextSp.paint(g);
			m_UI.Paint(g, getWidth(), getHeight());
			break;
		}
		flushGraphics();
	}
	public void commandAction(Command c, Displayable s){
		if( c == MenuCommand ){
			switch( m_nState ){	
			case GAME_END:							//游戏结束，显示按钮
			case GAME_GAMING:						//正在游戏，显示按钮	
				setState(GAME_BUTTON);
				break;
			case GAME_BUTTON:						//正显示按钮，退回游戏
				setState(GAME_GAMING);
				break;
			default:
				break;
			}
		}
	}
	//碰撞检测
	private void CheckCollision()
	{
		//冲击波与冲击波发生碰撞
		if( m_Player.m_Wave.collidesWith(m_Computer.m_Wave, true)){
			m_Player.m_Wave.setVisible(false);
			m_Computer.m_Wave.setVisible(false);
		}
		//设置碰撞区域，检测玩家攻击电脑
		m_Computer.ResetCollisionRect();
		m_Player.setCollisionRect();
		switch( m_Player.getState() ){
		case FighterSprite.FIGHTER_BOXING:
		case FighterSprite.FIGHTER_BOOT:
			if( m_Player.collidesWith(m_Computer, true) ){
				int life = m_Computer.getLife();
				life --;
				if( life <= 0 ){
					m_TextSp.setFrame(0);
					setState(GAME_END);
				}
				m_Computer.setLife(life);
				m_Computer.MoveBack(getWidth());
			}
		}
		//玩家冲击波攻击电脑
		if( m_Player.m_Wave.collidesWith(m_Computer, true) ){
			int life = m_Computer.getLife();
			life --;
			if( life <= 0 ){
				m_TextSp.setFrame(0);
				setState(GAME_END);
			}
			m_Computer.setLife(life);
			m_Player.m_Wave.setVisible(false);
			m_Computer.MoveBack(getWidth());
		}
		
		//设置碰撞区域，检测电脑攻击玩家
		m_Player.ResetCollisionRect();
		m_Computer.setCollisionRect();
		switch( m_Computer.getState() ){
		case FighterSprite.FIGHTER_BOXING:
		case FighterSprite.FIGHTER_BOOT:
			if( m_Computer.collidesWith(m_Player, true) ){
				int life = m_Player.getLife();
				life --;
				if( life <= 0 ){
					m_TextSp.setFrame(1);
					setState(GAME_END);
				}
				m_Player.setLife(life);
				m_Player.MoveBack(getWidth());
			}
		}
		//电脑冲击波攻击玩家
		if( m_Computer.m_Wave.collidesWith(m_Player, true) ){
			int life = m_Player.getLife();
			life --;
			if( life <= 0 ){
				m_TextSp.setFrame(1);
				setState(GAME_END);
			}
			m_Player.setLife(life);
			m_Computer.m_Wave.setVisible(false);
			m_Player.MoveBack(getWidth());
		}
	}
}