Jbuttons are not visible

Question

Hi,
Please Help.
I have defined a Jpanel which contains some buttons. This panel is initially collapsed and there is an expand button, clicking on which will expand the panel and buttons should be visible.
Sometimes the buttons are not visible after expanding the panel, or only some of them are visible.
This problem is not reproducible everytime.
For expanding and collapsing the Jpanel i am chaging the bound settings of the panel by using function
setBounds().
Can someone please help me with this issue?
Thanks

Answer 1

My intention was not to annoy anyone by posting my problem at two different forums. Sorry if i did that. I just wanted to get more opinions on this problem.
The suggestions i received on this one was mainly to use 'Layout Manager'. I tried using that but was running into other issues. If i have to use Layout Manager then i guess i have to change the design of the full window. I cannot use layout manger on just the part of the window which is giving problem (please let me know i am wrong). Also, I am new to Swings and not much familiar with 'Layout Manager'.
Is there a way to resolve this problem without using layout manager. This is not reproducible. It happens only in production.
I am pasting my code below -
I have modified the code as per the suggestions received from the forum to include repaint() and revalidate() methods.
The part i added is in bold. Please let me know what changes i should do to improve this and resolve the issue.
public static void main(String[] args) {
          initGUI();          
          frame = new JFrame();          
          frame.getContentPane().add(this);          
          frame.setBackground(LIGHT_BLUE);          
          frame.setTitle("ABC");
          logoImage = imgSPIcon.getImage();
          frame.setIconImage(logoImage);          
          frame.setSize(286,298);
          frame.setResizable(false);          
          frame.setVisible(false);  
                frame.getContentPane().validate();  
                frame.validate();     
private void initGUI() {
          try {          
               this.setSize(294, 280);
               this.setBackground(LIGHT_BLUE);
               this.setName("ABC");
               getContentPane().setBackground(this.LIGHT_BLUE);
               getContentPane().setLayout(null);               
               this.setFocusable(false);
               //collapse button used for expanding and collapsing the dial panel
                         m_btnCollapse = new JButton();
                         BottamPanel.add(m_btnCollapse);
                         m_btnCollapse.setBounds(163, 0, 112, 21);
                         m_btnCollapse.setIcon(imgExpandDialpad);
                         m_btnCollapse.setBorder(BorderFactory.createCompoundBorder(null, null));
                         m_btnCollapse.setBackground(new java.awt.Color(177, 201, 224));
                         m_btnCollapse.setContentAreaFilled(false);
               //Dial panel
                    DialPanel = new JPanel();                    
                    //getContentPane().add(DialPanel);                    
                    DialPanel.setBounds(0, 251, 280, 0);                    
                    DialPanel.setLayout(null);
                    DialPanel.setBackground(bkColor);                    
                         m_btn1 = new JButton();                         
                         m_btn1.setIcon(imgDPOne);
                         m_btn1.setContentAreaFilled(false);
                         m_btn1.setBounds(79, 0, 35, 28);
                         m_btn1.setBorderPainted(false);
                         DialPanel.add(m_btn1);
                         m_btn2 = new JButton();                         
                         m_btn2.setBounds(120, 0, 35, 28);
                         m_btn2.setIcon(imgDPTwo);
                         m_btn2.setContentAreaFilled(false);
                         m_btn2.setBorderPainted(false);
                         DialPanel.add(m_btn2);
                         m_btn3 = new JButton();                         
                         m_btn3.setBounds(161, 0, 35, 28);
                         m_btn3.setIcon(imgDPThree);
                         m_btn3.setContentAreaFilled(false);
                         m_btn3.setBorderPainted(false);
                         DialPanel.add(m_btn3);
                    //includes more such buttons
                                DialPanel.validate();
                    getContentPane().add(DialPanel);               
               //adding mouse listner for the collapse button
               JavaPhoneMouse aJavaPhoneMouse = new JavaPhoneMouse();
               m_btnCollapse.addMouseListener(aJavaPhoneMouse);
     //mouse listner.
     class JavaPhoneMouse extends java.awt.event.MouseAdapter {
          public void mouseClicked(java.awt.event.MouseEvent event) {
               Object object = event.getSource();
               if (object == m_btnCollapse)
                    m_btnCollapse_MouseClicked(event);
     //On expanding the dial panel the dial panel is expanded(the size changes) but the buttons are invisible. 
     void m_btnCollapse_MouseClicked(java.awt.event.MouseEvent event) {
          //if the dial pad is in expanded form it will collapse else it will be expanded.
          if (isDialPadCollapsed == false) {               
               DialPanel.setBounds(0, 251, 280, 0);
               DialPanel.revalidate();
               DialPanel.repaint();                              
               BottamPanel.setBounds(0, 251, 280, 21);
               m_btnCollapse.setIcon(imgExpandDialpad);               
               this.setSize(280, 277);               
               frame.setResizable(true);
               frame.setSize(286, 298);
               frame.setResizable(false);
                        frame.getContentPane().repaint();
               frame.repaint();                              
               isDialPadCollapsed = true;
          } else {               
               this.setSize(280, 408);               
               frame.setResizable(true);
               frame.setSize(286, 430);
               frame.setResizable(false);               
               BottamPanel.setBounds(0, 384, 280, 21);               
               DialPanel.setBounds(0, 251, 280, 133);     
                        DialPanel.revalidate();
               DialPanel.repaint();
               frame.getContentPane().repaint();
               frame.repaint();          
               m_btnCollapse.setIcon(imgCollDialpad);
               isDialPadCollapsed = false;
{code}
Thanks