Can I make a class holding multiple GUI components and make it visible?

Question

I am implementing an MDI where the different JInternalFrames are filled with a JPanel with components. Since the contents of my screen is dynamically generated, each screen can have multiple Jlabels, JTextFields, etc.
So I thought, I make a class containing the representation of one row of GUI components on my screen, which is: one JLAbel and 4 JTextFields.
Here is the code which adds the components to the panel:
// create panel
JPanel qpanel = new JPanel();
qpanel.setLayout(new BoxLayout(qpanel, BoxLayout.Y_AXIS));
qpanel.add(Box.createVerticalStrut(5));
//add rows to panel
for( int i = 0; i < nrRows; i++)
// qpanel.add(new JLabel("Hello how are you"));
qpanel.add(new ProcessRow("hello","how","are","you"));
// add panel to scrollpanel
this.getViewport().add(qpanel);
Here is the ProcessRow class:
public class ProcessRow extends JComponent
public JLabel rowLabel = null;
public JTextField myCost = null;
public JTextField saratogaCost = null;
public JTextField sapCost = null;
public JTextField totalCost = null;
public ProcessRow() {
super();
public ProcessRow(String LABEL,
String DEFAULTCOST,
String SARATOGACOST,
String SAPCOST){
super();
JLabel rowLabel = new JLabel(LABEL);
JTextField myCost = new JTextField(DEFAULTCOST, 6);
JTextField saratogaCost = new JTextField(SARATOGACOST, 6);
JTextField sapCost = new JTextField(SAPCOST, 6);
JTextField totalCost = new JTextField(6);
If I add the label "Hello how are you" directly to the panel, it shows fine but if I use my ProcessRow class, nothing shows.
How can I make it visible and if not,
how can I dynamically keep adding all these GUI components without loosing control over the components.
Thanks,
Johnny

Answer 1

Modify your ProcessRow:
(1) First extends JPanel ( Container, not Component)
(2) Add Label and TextField to the container
public class ProcessRow extends JPanel
public JLabel rowLabel = null;
public JTextField myCost = null;
public JTextField saratogaCost = null;
public JTextField sapCost = null;
public JTextField totalCost = null;
public ProcessRow() {
super();
public ProcessRow(String LABEL,
String DEFAULTCOST,
String SARATOGACOST,
String SAPCOST){
super();
JLabel rowLabel = new JLabel(LABEL);
JTextField myCost = new JTextField(DEFAULTCOST, 6);
JTextField saratogaCost = new JTextField(SARATOGACOST, 6);
JTextField sapCost = new JTextField(SAPCOST, 6);
JTextField totalCost = new JTextField(6);
// add everything to the container.
add(rowLabel);
add(myCost);
add(sapCost);
add(totalCost);
}