public void luncur(){
        panelUtama.setLayout(new BorderLayout());
        panelIsi.setLayout(new GridLayout(2,2));
        panelTombol.setLayout(new FlowLayout());
        panelUtama.add(lSignIn, BorderLayout.NORTH);
        panelIsi.add(tfUsername);
        panelIsi.add(lUsername);
        panelIsi.add(pfPassword);
        panelIsi.add(lPassword);
        panelTombol.add(bLogin);
        panelUtama.add(panelIsi, BorderLayout.CENTER);
        panelUtama.add(panelTombol, BorderLayout.SOUTH);
        //f.add(panelUtama);
        f.setVisible(true);
        f.setSize(320, 240);
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(f.EXIT_ON_CLOSE);
    }