private void login() {
		panel = new LoginPanel(this);
		centerWindow();
		this.add(panel);
		panel.updateUI();
		((LoginPanel) panel).getSignInBtn().addActionListener(new ActionListener(){
			
			@Override
			public void actionPerformed(ActionEvent e) {
			String user = ((JTextField)panel.getComponent(1)).getText();
			String code = ((JTextField)panel.getComponent(3)).getText();
				if(new DBInterface().userExists(user)) {
					
					if(new DBInterface().checkCode(user, code)) {
						
						if(new DBInterface().checkTime(user)) {
							
							showCode(user);
							
						} else {
							new WrongLoginWindow(WrongLoginWindow.TIME);
						}
						
					} else {
						new WrongLoginWindow(WrongLoginWindow.CODE);
					}
					
				} else {
					new WrongLoginWindow(WrongLoginWindow.USERNAME);
				}
			}
		});
	}