Applet-Panel, background color and size problem

Question

I am writing an applet with simple form.
Form is having 3 rows and 2 cols (label and textfield). Each row I want to display in different color. So I created each row with 2 separate panel (one for label and one for text field - of which I set the backgroung color).
The total form is in one panel with grid layout (2 colmns).
My problems are
1)The space between label and text field (col width) can not be resized. I tried to use setSize but not giving any effect.
2)Another problem is when I am seting the background color, the textfield is also changing the color (textfield I want to white color only). This does not have any effect on Choice
3)The first label I wanted to use simple break but could not. I tried \n\t, \n, chr(13) + chr(10) etc but not getting any result so created separate panel.
My code goes here:
import java.awt.*;
import java.applet.*;
import java.awt.event.*;
public class test1 extends Applet{
protected TextField refnoTextField=null, payerTextField=null, amtTextField=null;
protected Choice typeChoice;
public void init() {
     /* The mainPanel layouts components with BorderLayout manager
          which will hold form and button panel */
     Panel mainPanel = new Panel(new BorderLayout());
     Panel taxformPanel=new Panel(new GridLayout(3,2));
     Label l;
     //panel for tax ref no label
     Panel refnoLabelMainPanel = new Panel(new FlowLayout(FlowLayout.LEFT));
//here wanted to use simple line break but \n\t does not seems to work not even chr (10), chr(13)
//so created separate panel (Payment Voucher Or \n\t Reference no.
     Panel refnoLabelPanel = new Panel(new GridLayout(2,1));
     l = new Label("Payment Voucher Or");
l.setFont(new Font("Helvetica", Font.BOLD,10));
     refnoLabelPanel.add (l);
     l = new Label("Tax Reference No:");
l.setFont(new Font("Helvetica", Font.BOLD,10));
     refnoLabelPanel.add (l);
     refnoLabelMainPanel.add(refnoLabelPanel);
     refnoLabelMainPanel.setBackground(Color.blue);
     //panel for tax ref no text field
     Panel refnoTextFieldPanel = new Panel(new FlowLayout(FlowLayout.LEFT));
     refnoTextField = new TextField(20);
     refnoTextFieldPanel.add(refnoTextField);
     refnoTextFieldPanel.setBackground(Color.blue);
     //panel for tax type label
     Panel typeLabelPanel = new Panel(new FlowLayout(FlowLayout.LEFT));
     l = new Label("Tax Type:");
l.setFont(new Font("Helvetica", Font.BOLD,10));
     typeLabelPanel.add (l);
     typeLabelPanel.setBackground(Color.yellow);
     //panel for tax type choice
     Panel typeChoicePanel = new Panel(new FlowLayout(FlowLayout.LEFT));
     typeChoice = new Choice();
     typeChoice.add("Personal Tax");
     typeChoice.add("Income Tax");
     typeChoicePanel.add(typeChoice);
     typeChoicePanel.setBackground(Color.yellow);     
     //panel for tax payers name label
     Panel payerLabelPanel = new Panel(new FlowLayout(FlowLayout.LEFT));
     l = new Label("Tax Payer's Name:");
l.setFont(new Font("Helvetica", Font.BOLD,10));
     payerLabelPanel.add (l);
     payerLabelPanel.setBackground(Color.blue);
     //panel for tax payer field
     Panel payerTextFieldMainPanel = new Panel(new FlowLayout(FlowLayout.LEFT));
     Panel payerTextFieldPanel = new Panel(new GridLayout(2,1));
     payerTextField = new TextField(20);
     payerTextFieldPanel.add(payerTextField);
     l = new Label(" (as per NRIC or Passport)");
l.setFont(new Font("Helvetica", Font.BOLD,8));
     payerTextFieldPanel.add (l);
     payerTextFieldMainPanel.add(payerTextFieldPanel);
     payerTextFieldMainPanel.setBackground(Color.blue);
     taxformPanel.add(refnoLabelMainPanel);
     taxformPanel.add(refnoTextFieldPanel);
     taxformPanel.add(typeLabelPanel);
     taxformPanel.add(typeChoicePanel);
     taxformPanel.add(payerLabelPanel);
     taxformPanel.add(payerTextFieldMainPanel);
     /* buttonPanel to hold all buttons */
     Panel buttonPanel = new Panel();
     buttonPanel.setLayout(new FlowLayout(FlowLayout.CENTER));
     Button continueButton = new Button("Continue");
     continueButton.addActionListener(new ActionListener() {
          public void actionPerformed(ActionEvent e) {
                    continueButtonAction();
     Button clearButton = new Button("Clear");
     clearButton.addActionListener(new ActionListener()     {
          public void actionPerformed(ActionEvent e)     {
               clearButtonAction();
     Button cancelButton = new Button("Cancel");
     cancelButton.addActionListener(new ActionListener()     {
          public void actionPerformed(ActionEvent e)     {
               cancelButtonAction();
     buttonPanel.add(continueButton);
     buttonPanel.add(clearButton);
     buttonPanel.add(cancelButton);
     mainPanel.add("Center", taxformPanel);
     mainPanel.add("South", buttonPanel);
     add(mainPanel);
} // public void init()     
public void continueButtonAction() {
     MessageDialog d=new MessageDialog("Confirm","Continue? ",true, 430, 150);
     System.out.println ("Continue Button Pressed");
}//continueButtonAction
public void clearButtonAction()     {
     System.out.println ("Reset Button Pressed");
}//clearButtonAction
public void cancelButtonAction()     {
     MessageDialog d=new MessageDialog("Confirm","Cancel Button ? ",true, 430, 150);
     System.out.println ("Cancel Button Pressed");
} // cancelButtonAction
} // TaxPaymentApplet3
Please help,
manisha

Answer 1

I do not want to go into detail, but there are some hints you can follow.
I am talking about AWT, not swing, you should decide which one you will use and don't mix the two of them.
If you want to run your applet in current browsers without requiring the java plugin, you should be aware, that most browsers support old versions of java and many convenient methods and classes are missing :-(
So
You can change the size of a label by putting it in a panel ( labelPanel ), whose layout is set to FlowLayout. Then you put in labelPanel another empty panel ( emptyPanel ), whose layout is set to null, and you set the width of the empty panel to whatever you want ( this is the gap between the label and the next component ), an the height to the least nonsero number possible, i.e. 1. Well, you can add to the labelPanel more components, if you wish. So, when you want a gap, use an empty panel with a fixed size.
You cannot use line break in a label. You should place more labels in a panel instead. I am not sure if the direction of FlowLayout can be set to vertical, but very probably it can. If so, that is your solution. If not - see what other layout managers you have available, but make sure your choice belongs to java.awt ! BorderLayout allows you to use up to three labels (=> 3 lines). And if nothing fits your needs, ... write a layout manager.
Well, hope I could help.