maincanvas.java

J2ME手机游戏50例

package demo;
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.Sprite;

public class MainCanvas extends GameCanvas implements Runnable{
	private boolean	m_bRunning;			   	//控制线程运行
	public Sprite		m_spButton;				//按钮对象
	public RMSScore 	m_Score;				//记录对象
	public int			m_nTimes = 0;			//管理时间
	public Font			m_Font;					//字体对象
	public MainCanvas(){
		super(false);
		m_Score = new RMSScore();				//分配内存空间
		m_Score.LoadHighScore();				//读取最高分
		
		try{//创建字体
			m_Font 	= Font.getFont(Font.FACE_PROPORTIONAL, 
							Font.STYLE_BOLD, Font.SIZE_LARGE);
		}
		catch(Exception e){//创建失败,则采用系统默认字体
			m_Font  = Font.getDefaultFont();
		}
		try{//读取图片资源,注意资源的路径
			Image image = Image.createImage("/demo/Button.png");
			m_spButton = new Sprite( image, 25, 25 );
			m_spButton.setFrame( 0 );
			m_spButton.setPosition( getWidth()/2 - 12, 90 );
		}
		catch(Exception e){}
		Start();								//启动线程
	}
	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 StartTime(){					//开始计时
		m_nTimes = 600;							//600*100=60000毫秒=1分钟
		m_Score.m_nCurScore = 0;
	}
	protected void keyPressed(int keyCode){
		if( m_nTimes <= 0 ){					//计时尚未开始
			if( keyCode == KEY_NUM0 )			//按下0号键
				StartTime();
			return;
		}
		m_Score.m_nCurScore ++;					//增加分数
		m_spButton.setFrame( 1 );				//设置按钮
	}
	public void Input(){
	}
	public void Logic(){
		if( m_nTimes > 0 ){						//计时
			m_nTimes --;
			if( m_nTimes <= 0 ){				//结束游戏
				m_Score.SaveHighScore();
			}
		}
	}
	public void Paint(){
		Graphics g = getGraphics();
		//用黑色清屏
		g.setColor(0);
		g.fillRect( 0, 0, getWidth(), getHeight() );
		
		//设置当前颜色及当前字体
		g.setColor(0xFFFFFFFF);
		g.setFont(m_Font);
		StringBuffer temp 	= new StringBuffer();
		StringBuffer temp2 	= new StringBuffer();
		StringBuffer temp3 	= new StringBuffer();
		
		//拼接字符
		temp2.append( "最高分:" );
		temp2.append( m_Score.m_nHighScore );
		temp3.append( "本次得分:" );
		temp3.append( m_Score.m_nCurScore );
		if( m_nTimes <= 0 )
			temp.append( "按0号键开始计时" );	
		else{
			temp.append( "剩余时间" );
			temp.append( m_nTimes / 10 );
			temp.append( "秒" );
		}
		//显示文字信息
		g.drawString( temp.toString(), 20, 10, 0 );
		g.drawString( temp2.toString(), 20, 30, 0 );
		g.drawString( temp3.toString(), 20, 50, 0 );
		//显示按钮
		m_spButton.paint(g);
		m_spButton.setFrame( 0 );
		flushGraphics();
	}
}