public class JLaser extends JPanel implements Runnable { public JLaser() { this.setSize(1, 10); } @Override protected void paintComponent(Graphics g) { super.paintComponent(g); g.setColor(Color.YELLOW); g.drawLine(0, 0, 0, 9); } public void fire() { Thread thread = new Thread(this); thread.setDaemon(true); thread.start(); } @Override public void run() { while (this.getY() >= 0) { this.setLocation(this.getX(), this.getY() - 10); try { Thread.sleep(20); } catch (InterruptedException ex) { } } setVisible(false); this.getParent().remove(this); } }
Codice da utilizzare nel Main:
@Override public void mouseMoved(MouseEvent me) { pnlAstronave.setLocation(me.getX()-5, pnlAstronave.getY()); } @Override public void keyReleased(KeyEvent ke) { if (ke.getKeyChar()==' ') { JLaser laser = new JLaser(); laser.setBounds(pnlAstronave.getX()+5, pnlAstronave.getY()-10, 1, 10); panel.add(laser); laser.setVisible(true); laser.fire(); } }