I can't see the components of my JFrame...

Question

Hi!
I have made a JFrame and when I run it using the main method, it displays all the components (buttons etc, you know). It works fine. But if I don't use the main method and call it through another JFrame it doesn't display the components. It is empty! What do I do wrong?
Thanks in advance.

Answer 1

The first class that has the problem is this:
public class RantevouForm extends JFrame implements ActionListener{
     private Container cp;
     private JButton b1 = new JButton("��� ��������"),
                         b2 = new JButton("��������"),
                         b3 = new JButton("�����������");
     private JLabel simera = new JLabel();     
     private Vector rows = new Vector();
     private Vector columns= new Vector();
     private String[] columnNames = { "���","��������","������","�������"};
     private DefaultTableModel tabModel=new DefaultTableModel();
     private JTable table = new JTable(tabModel);
private JScrollPane scrollpane = new JScrollPane(table);
     public RantevouForm() {
          cp = getContentPane();     
          JPanel p1 = new JPanel();
          p1.add(b1);
          p1.add(b2);
          p1.add(b3);
          b1.addActionListener(this);
          b2.addActionListener(this);
          b3.addActionListener(this);
          SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
          rightNow.set(year,month,day_of_month);
          simera.setText("������: "+sdf.format(rightNow.getTime()));
          cp.add(simera,BorderLayout.NORTH);
          cp.add(p1,BorderLayout.WEST);
          cp.add(scrollpane,BorderLayout.CENTER);
          addColumn(columnNames);
          tabModel.setDataVector(rows,columns);
          table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
The class that calls the above one is:
class MyCalendar extends JPanel implements ActionListener{
     Container cp;
     JButton[] btn = new JButton[42];
     JLabel[] lb = new JLabel[7];
     Calendar now = Calendar.getInstance();
     int month = now.get(Calendar.MONTH);
     int year = now.get(Calendar.YEAR);
     JLabel lbl = new JLabel("",JLabel.CENTER);
     public MyCalendar(){
          buildGUI();
          setDates();
     public void buildGUI(){
          JPanel midPanel = new JPanel(new GridLayout(7,7,0,0));
          midPanel.setPreferredSize(new Dimension(200,200));
          for(int i = 0; i < lb.length; i++){
          lb[i] = new JLabel();
          lb.setFont(new Font("Garamond",Font.PLAIN,14));
          lb[i].setText(header[i]);
          lb[i].setHorizontalAlignment(JLabel.CENTER);
          midPanel.add(lb[i]);
     for(int x = 0; x < btn.length; x++){
     final int selection = x;
     btn[x] = new JButton();
     btn[x].setFocusPainted(false);
     btn[x].addActionListener(this);
     midPanel.add(btn[x]);
public void actionPerformed(ActionEvent ae){
          RantevouForm ran = new RantevouForm();
          ran.setVisible(true);
          ran.setSize(750,400);
          ran.setResizable(false);
An object MyCalendar appears on my main screen.
I hope you can help me!