enemy.java

用J2ME开发的射击游戏

import java.util.Random;
import javax.microedition.lcdui.Image;

public class Enemy extends PlaneSprite{
	private Random 		m_Random;
	Enemy( Image img, int nWidth, int nHeight ){
		super( img, nWidth, nHeight );
		m_Random 		= new Random();
	}
	public void Logic( ){
		super.Logic();
		if( isVisible() == false )
			return;
		int nX = getRefPixelX() + m_nSpeedX;
		int nY = getRefPixelY() + m_nSpeedY;
		setRefPixelPosition( nX, nY );
		if( getRefPixelX() < -10 || 
			getRefPixelX() > MainCanvas.m_nScrWidth + 10 ||
			getRefPixelY() < -10 || 
			getRefPixelY() > MainCanvas.m_nScrHeight + 10 )
				setVisible(false);
		CreateBullet();
	}
	private void CreateBullet( ){
		if( m_Bullet.isVisible() )
			return;
		int RS = Math.abs(m_Random.nextInt() % 30 );
		if( RS != 0 )
			return;
		int nSpeedX = m_Random.nextInt() % 2;
		int nSpeedY = Math.abs(m_Random.nextInt() % 2 ) + 1;
		m_Bullet.SetSpeed( nSpeedX, nSpeedY );
		m_Bullet.setRefPixelPosition( 
				getRefPixelX(), getRefPixelY() );
		m_Bullet.setVisible(true);
	}
}