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Thread: Error Objects Swing

  1. #1
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    Default Error Objects Swing

    hello I have a problem with a JFrame I can not access objects JButtom to use their attributes, will not let me enable or disable the objects I have declared as public and not anything I can use only within the class constructor

    Este es el error que me sale

    Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at logica.frmRegistro.onVariables(frmRegistro.java:20 8)
    at logica.frmRegistro.access$0(frmRegistro.java:199)
    at logica.frmRegistro$2.actionPerformed(frmRegistro.j ava:139)
    at javax.swing.AbstractButton.fireActionPerformed(Abs tractButton.java:1995)
    at javax.swing.AbstractButton$Handler.actionPerformed (AbstractButton.java:2318)

    package logica;
     
    import java.awt.BorderLayout;
    import java.awt.EventQueue;
    import java.awt.Font;
     
    import javax.swing.JButton;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.JTable;
    import javax.swing.border.EmptyBorder;
    import javax.swing.JTextField;
     
    import datos.connDb;
    import javax.swing.border.TitledBorder;
    import javax.swing.border.LineBorder;
    import java.awt.Color;
    import javax.swing.GroupLayout;
    import javax.swing.GroupLayout.Alignment;
    import javax.swing.JLabel;
    import javax.swing.LayoutStyle.ComponentPlacement;
    import java.awt.event.ActionListener;
    import java.awt.event.ActionEvent;
     
    public class frmRegistro extends JFrame {
     
    	private JPanel contentPane;
     
    	connDb objDb;
    	private JTextField txtId;
    	private JTextField txtNombres;
    	private JTextField txtDni;
    	private JTextField txtDireccion;
    	private JTextField txtCargo;
    	private JTextField txtTelefono;
     
    	private JButton btnNuevo;
    	private JButton btnInsertar;
    	private JButton btnBuscar;
    	private JButton btnActualizar;
    	private JTable table;
     
     
    	/**
    	 * Launch the application.
    	 */
     
    	public static void main(String[] args) {
    		EventQueue.invokeLater(new Runnable() {
    			public void run() {
    				try {
    					frmRegistro frame = new frmRegistro();
    					frame.setVisible(true);
    				} catch (Exception e) {
    					e.printStackTrace();
    				}
    			}
    		});
    	}
     
    	/**
    	 * Create the frame.
    	 */
    	public frmRegistro() {
    		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    		setBounds(100, 100, 732, 411);
    		setFont(new Font("Droid Sans", Font.BOLD, 11));
    		setTitle("Registro de Usuarios");
    		contentPane = new JPanel();
    		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    		setContentPane(contentPane);
     
    		JPanel panel = new JPanel();
    		panel.setBorder(new TitledBorder(new LineBorder(new Color(99, 130, 191)), "Registro de datos", TitledBorder.LEADING, TitledBorder.TOP, null, new Color(128, 0, 0)));
    		panel.setLayout(null);
    		panel.setBounds(12, 12, 706, 141);
     
    		txtId = new JTextField();
    		txtId.setBounds(126, 39, 114, 19);
    		txtId.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		panel.add(txtId);
    		txtId.setColumns(10);
     
    		table = new JTable();
    		GroupLayout gl_contentPane = new GroupLayout(contentPane);
    		gl_contentPane.setHorizontalGroup(
    			gl_contentPane.createParallelGroup(Alignment.LEADING)
    				.addGroup(gl_contentPane.createSequentialGroup()
    					.addGap(7)
    					.addComponent(panel, GroupLayout.PREFERRED_SIZE, 706, GroupLayout.PREFERRED_SIZE)
    					.addContainerGap(GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
    				.addGroup(Alignment.TRAILING, gl_contentPane.createSequentialGroup()
    					.addContainerGap(GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
    					.addComponent(table, GroupLayout.PREFERRED_SIZE, 701, GroupLayout.PREFERRED_SIZE)
    					.addContainerGap())
    		);
    		gl_contentPane.setVerticalGroup(
    			gl_contentPane.createParallelGroup(Alignment.TRAILING)
    				.addGroup(gl_contentPane.createSequentialGroup()
    					.addComponent(panel, GroupLayout.PREFERRED_SIZE, 148, GroupLayout.PREFERRED_SIZE)
    					.addPreferredGap(ComponentPlacement.UNRELATED)
    					.addComponent(table, GroupLayout.PREFERRED_SIZE, 205, GroupLayout.PREFERRED_SIZE)
    					.addContainerGap())
    		);
     
    		txtNombres = new JTextField();
    		txtNombres.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		txtNombres.setBounds(453, 39, 240, 19);
    		panel.add(txtNombres);
    		txtNombres.setColumns(10);
     
    		txtDni = new JTextField();
    		txtDni.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		txtDni.setBounds(126, 59, 114, 19);
    		panel.add(txtDni);
    		txtDni.setColumns(10);
     
    		txtDireccion = new JTextField();
    		txtDireccion.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		txtDireccion.setBounds(126, 79, 230, 19);
    		panel.add(txtDireccion);
    		txtDireccion.setColumns(10);
     
    		txtCargo = new JTextField();
    		txtCargo.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		txtCargo.setBounds(453, 59, 114, 19);
    		panel.add(txtCargo);
    		txtCargo.setColumns(10);
     
    		txtTelefono = new JTextField();
    		txtTelefono.setFont(new Font("Droid Sans", Font.PLAIN, 11));
    		txtTelefono.setBounds(453, 79, 114, 19);
    		panel.add(txtTelefono);
    		txtTelefono.setColumns(10);
     
    		JButton btnNuevo = new JButton("Nuevo");
    		btnNuevo.addActionListener(new ActionListener() {
    			public void actionPerformed(ActionEvent e) {
    				onVariables();
    			}
    		});
    		btnNuevo.setBounds(100, 110, 117, 25);
    		panel.add(btnNuevo);
    		contentPane.setLayout(gl_contentPane);
     
    		JButton btnInsertar = new JButton("Insertar");
    		btnInsertar.setBounds(239, 110, 117, 25);
    		panel.add(btnInsertar);
     
    		JButton btnBuscar = new JButton("Buscar");
    		btnBuscar.setBounds(378, 110, 117, 25);
    		panel.add(btnBuscar);
     
    		JButton btnActualizar = new JButton("Actualizar");
    		btnActualizar.setBounds(517, 110, 117, 25);
    		panel.add(btnActualizar);
     
    		JLabel lblNewLabel = new JLabel("Id Usuario :");
    		lblNewLabel.setBounds(48, 39, 74, 19);
    		lblNewLabel.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		panel.add(lblNewLabel);
    		contentPane.setLayout(gl_contentPane);
     
    		JLabel lblNewLabel_1 = new JLabel("Nombres y Apellidos :");
    		lblNewLabel_1.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		lblNewLabel_1.setBounds(321, 39, 127, 19);
    		panel.add(lblNewLabel_1);
    		contentPane.setLayout(gl_contentPane);
     
    		JLabel lblNewLabel_2 = new JLabel("Doc. Identidad :");
    		lblNewLabel_2.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		lblNewLabel_2.setBounds(24, 59, 97, 19);
    		panel.add(lblNewLabel_2);
    		contentPane.setLayout(gl_contentPane);
     
    		JLabel lblNewLabel_3 = new JLabel("Dirección :");
    		lblNewLabel_3.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		lblNewLabel_3.setBounds(52, 79, 70, 19);
    		panel.add(lblNewLabel_3);
    		contentPane.setLayout(gl_contentPane);
     
    		JLabel lblNewLabel_4 = new JLabel("Cargo :");
    		lblNewLabel_4.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		lblNewLabel_4.setBounds(399, 59, 48, 19);
    		panel.add(lblNewLabel_4);
    		contentPane.setLayout(gl_contentPane);
     
    		JLabel lblNewLabel_5 = new JLabel("Telefono :");
    		lblNewLabel_5.setFont(new Font("Droid Sans", Font.BOLD, 11));
    		lblNewLabel_5.setBounds(383, 79, 63, 19);
    		panel.add(lblNewLabel_5);
    		contentPane.setLayout(gl_contentPane);	
    		offVariables();
    		btnInsertar.setEnabled(false);
    		btnBuscar.setEnabled(false);
    		btnActualizar.setEnabled(false);
    	}
     
    	private void onVariables()
    	{
    		txtId.setEnabled(true);
    		txtNombres.setEnabled(true);
    		txtDni.setEnabled(true);
    		txtCargo.setEnabled(true);
    		txtDireccion.setEnabled(true);
    		txtTelefono.setEnabled(true);
     
    		btnNuevo.setEnabled(true);
    		btnActualizar.setEnabled(true);
    		btnBuscar.setEnabled(true);
     
    	}
     
    	private void offVariables()
    	{
    		txtId.setEnabled(false);
    		txtNombres.setEnabled(false);
    		txtDni.setEnabled(false);
    		txtCargo.setEnabled(false);
    		txtDireccion.setEnabled(false);
    		txtTelefono.setEnabled(false);
    		//btnInsertar.setEnabled(false);
    		//btnBuscar.setEnabled(false);
    		//btnActualizar.setEnabled(false);
    	}
    }


  2. #2
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    Default Re: Error Objects Swing

    What line is 208, and can you find where you declared all the variables on that line?
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