GUI Problem (Swing JFrame/JPanel). HELP!

Question

Hi,
I made an small application for calculate some things.
I download i piece of code for creating bar chart and i icluded in my code. But i have problem when i am trying to show the chart in the Frame. All the buttons, textfields, labels goes to left and half are hiding.
If i open the chart on a new frame i dont have problem.
the problem apears when after i put the panel in the frame i try to put the chart in the frame. Look the code:
add(p);     //Put the panel in the Frame
this.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant")); // <-- The problem!!that command mades me the problem!
Here are 2 screenshots
1. When i put the chart in the Frame (the problem)
http://www.iweb.gr/images/InFrame.jpg
2. When i put the chart on new frame (works fine)
http://www.iweb.gr/images/NewFrame.jpg
Hopes someone can help. Thanks
The code List:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
//The main class of the program
public class PlantFertilizer  extends JFrame{//The main class is a subclass of Frame
     private Label lN, lP,lK;//These show the value of the observable
     public TextField tN, tP, tK;
     private MyData thedata;//The observable we are going to watch
     private double[] values=new double[3];
    private String[] names=new String[3];
    private String title;
public PlantFertilizer(){
     thedata=new MyData();// create the observable
     addWindowListener(new WindowAdapter(){//if user closes the Frame, quit
          public void windowClosing(WindowEvent e){
               System.exit(0);
     setSize(400,500);//Set size
     setTitle(getClass().getName()+" By Pantelis Stoumpis");
     JPanel p = new JPanel();    //Make a panel for buttons and output
     //Input Data Area
     p.add(new Label("-------------------------Input Data Area--------------------------",Label.CENTER));
     p.add(new Label("Nitrogen (N)"));
     tN = new TextField();p.add(tN);
     p.add(new Label("Phosphorus (P)"));
     tP = new TextField();p.add(tP);
     p.add(new Label("Potassium (K)"));
     tK = new TextField();p.add(tK);
     lN=new Label("N = %", Label.CENTER);
     p.add(lN);     //Put the N label in the panel
     lP=new Label("P = %", Label.CENTER);
     p.add(lP);          //Put the P label in the panel
     lK=new Label("K = %", Label.CENTER);
     p.add(lK);          //Put the K label in the panel
     addButton(p,"Apply",          //Apply new Values
     new ActionListener(){
     public void actionPerformed(ActionEvent evt){
          int iNt = Integer.parseInt(tN.getText());
          int iPt = Integer.parseInt(tP.getText());
          int iKt = Integer.parseInt(tK.getText());
          thedata.addOne(iNt,iPt,iKt);          //which adds one to the observable
          JFrame f = new JFrame();
         f.setSize(400, 300);
          values[0] = 40;
         names[0] = "N";
         values[1] = 20;
         names[1] = "P";
         values[2] = 30;
         names[2] = "K";
         f.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant"));
          f.setVisible(true);
     addButton(p,"Close",          //add a close button to quit the program
     new ActionListener(){
     public void actionPerformed(ActionEvent evt){
          System.exit(0);
add(p);     //Put the panel in the Frame
this.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant")); // <-- The problem!!
//A utility function to add a button with a given title and action
public void addButton(Container c, String title,ActionListener a)
          Button b=new Button(title);
          c.add(b);
          b.addActionListener(a);
public class ChartPanel extends JPanel {
  private double[] values;
  private String[] names;
  private String title;
  public ChartPanel(double[] v, String[] n, String t) {
    names = n;
    values = v;
    title = t;
  public void paintComponent(Graphics g) {
    super.paintComponent(g);
    if (values == null || values.length == 0)
      return;
    double minValue = 0;
    double maxValue = 0;
    for (int i = 0; i < values.length; i++) {
      if (minValue > values)
minValue = values[i];
if (maxValue < values[i])
maxValue = values[i];
//Dimension d = getSize();
//int clientWidth = d.width;
//int clientHeight = d.height;
//int barWidth = clientWidth / values.length;
//Dimension d = 100;
     int clientWidth = 100;
     int clientHeight = 150;
int barWidth = clientWidth / values.length;
Font titleFont = new Font("SansSerif", Font.BOLD, 12);
FontMetrics titleFontMetrics = g.getFontMetrics(titleFont);
Font labelFont = new Font("SansSerif", Font.PLAIN, 10);
FontMetrics labelFontMetrics = g.getFontMetrics(labelFont);
int titleWidth = titleFontMetrics.stringWidth(title);
int y = titleFontMetrics.getAscent();
int x = (clientWidth - titleWidth) / 2;
g.setFont(titleFont);
g.drawString(title, 10, 300);
int top = titleFontMetrics.getHeight();
int bottom = labelFontMetrics.getHeight();
if (maxValue == minValue)
return;
double scale = (clientHeight - top - bottom) / (maxValue - minValue);
y = clientHeight - labelFontMetrics.getDescent();
g.setFont(labelFont);
for (int i = 0; i < values.length; i++) {
int valueX = i * barWidth + 1;
int valueY = top;
int height = (int) (values[i] * scale);
if (values[i] >= 0)
valueY += (int) ((maxValue - values[i]) * scale);
else {
valueY += (int) (maxValue * scale);
height = -height;
g.setColor(Color.red);
g.fillRect(valueX, valueY, barWidth - 2, height);
g.setColor(Color.black);
g.drawRect(valueX, valueY, barWidth - 2, height);
int labelWidth = labelFontMetrics.stringWidth(names[i]);
x = i * barWidth + (barWidth - labelWidth) / 2;
g.drawString(names[i], x, y);
//main is called when we start the application
public static void main(String[]args){
               PlantFertilizer od = new PlantFertilizer();//make an observationsDemo frame
               NWatcher watchitN = new NWatcher(od.lN);//make an observer
               od.thedata.addObserver(watchitN);//register observer with the observable
               PWatcher watchitP = new PWatcher(od.lP);//make an observer
               od.thedata.addObserver(watchitP);//register observer with the observable
               KWatcher watchitK = new KWatcher(od.lK);//make an observer
               od.thedata.addObserver(watchitK);//register observer with the observable
               od.setVisible(true);//show the frame on the screen

Answer 1

Why are you putting Labels and TextFields (heavyweight AWT components) into a lightweight JPanels?
What's the first rule of Swing? DO NOT MIX heavyweight AWT components and lightweight Swing components. Period. Never.
There's Swing equivalents for every single AWT component, and then some. There's no excuse for not using them.
However, if this chart library code is AWT based, then you should make a completely AWT based UI. Or find a different library based on Swing (like JFreeChart).
And finally:
add(p);     //Put the panel in the Frame
this.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant")); // <-- The problem!!is wrong....
add(p);      // <-- The problem!!
this.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant"));You don't call add on JFrame or JDialog to add things to it, unless you know what you're doing. And you clearly don't, else you wouldn't have done it. What you probably want to do is this:
this.getContentPane().add(p, BorderLayout.SOUTH);
this.getContentPane().add(new ChartPanel(values, names, "Fertilizer Plant"), BorderLayout.CENTER);