bricksprite.java

来自「J2ME编程的50个例子,适合掌上系统的编程」· Java 代码 · 共 50 行

package demo;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.Sprite;


public class BrickSprite extends Sprite{
	//砖块的状态值
	public static final int BRICK_FIX 		= 0;		//固定在屏幕上方	
	public static final int BRICK_DROP 		= 1;		//下落
	public static final int BRICK_HIDE 		= 2;		//消失
	public static final int BRICK_STATE_NUM 	= 3;		//状态总数
	private int m_nState = BRICK_FIX;
	public BrickSprite( Image image, int frameWidth, int frameHeight){
		super(image, frameWidth, frameHeight);		
		defineReferencePixel(frameWidth / 2, frameHeight / 2);
		setState(BRICK_HIDE);
	}
	//得到当前状态
	public int getState(){
		return m_nState; 
	}
	//设置当前状态
	public void setState( int state ){
		if( state < 0 || state >= BRICK_STATE_NUM )
			return;
		m_nState = state;
		switch( m_nState ){
		case BRICK_FIX:
		case BRICK_DROP:
			setVisible(true);
			break;
		case BRICK_HIDE:
			setVisible(false);
			break;
		}
	}
	//逻辑操作,处理不同状态下砖块的运动
	public void Logic( int scrHeight ){
		switch( m_nState ){
		case BRICK_DROP:
			int y = getRefPixelY();
			y +=2;
			setRefPixelPosition(getRefPixelX(), y);
			if( y > scrHeight )
				setState(BRICK_HIDE);
			break;
		}
	}
}