Ask many times, almost despaired.

I'm using j2se 1.5 and do not have access to the GroupLayout class.

import java.awt.*;

import java.awt.event.*;

import java.awt.geom.*;

import java.util.Hashtable;

import javax.swing.*;

import javax.swing.event.*;

public class ComboxRx2 extends JApplet {

private Drawing drawing;

private JPanel jPanel1;

private JSlider dJSlider;

private JComboBox jComboBox1;

private JComboBox jComboBox2;

private JComboBox jComboBox3;

//private Container panel;

private int id;

private String af[] = {"Paint","No Paint"};

private double scale=1;

private int a;

private String energyId[] ={"one","two"};

public void init() {

try {

java.awt.EventQueue.invokeAndWait(new Runnable() {

public void run() {

initComponents();

}

});

} catch (Exception ex) {

ex.printStackTrace();

}

}

private void initComponents() {

jPanel1 = new JPanel();

jComboBox1 = new JComboBox();

jComboBox2 = new JComboBox();

jComboBox3 = new JComboBox();

int min = 1, max = 16, inc = 5;

dJSlider = new JSlider(min, max, 6);

dJSlider.setMajorTickSpacing(5);

dJSlider.setMinorTickSpacing(1);

dJSlider.setSnapToTicks(true);

dJSlider.setLabelTable(getLabelTable(min, max, inc));

dJSlider.setPaintTicks(true);

dJSlider.setPaintLabels(true);

dJSlider.addChangeListener(new ChangeListener() {

public void stateChanged(ChangeEvent e) {

int value = ((JSlider)e.getSource()).getValue();

double scale = (value+4)/10.0;drawing.setscale(scale);

}

});

//panel = getContentPane();panel.add(jPanel1);

// Have the variables a, id and scale been initialized/given values?

drawing = new Drawing(a,id,scale); // probably wrong here around

// Using a BorderLayout constraint: what layout does jPanel1 have?

// Until/unless you set it the default layout manager is FlowLayout.

//jPanel1.add(drawing,"Center");// probably wrong here

// You must set a containers layout manager before adding components.

//jPanel1.setLayout(new GridBagLayout());

jComboBox1.setModel(new DefaultComboBoxModel(energyId));

jComboBox1.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JComboBox cb = (JComboBox)e.getSource();

id = cb.getSelectedIndex();

drawing.setid(id);

}

});

jPanel1.setLayout(new GridBagLayout());

GridBagConstraints gbc = new GridBagConstraints();

// Configure constraints as you go...

gbc.insets = new Insets(2,2,2,2);

gbc.weightx = 1.0;

jPanel1.add(jComboBox1, gbc);

jComboBox2.setModel(new DefaultComboBoxModel(af));

jComboBox2.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

JComboBox cc = (JComboBox)e.getSource();

a = cc.getSelectedIndex();

drawing.seta(a);

}

});

jPanel1.add(jComboBox2, gbc);

jComboBox3.setModel(new DefaultComboBoxModel(

new String[] { "Item 1", "Item 2", "Item 3", "Item 4" }));

jPanel1.add(jComboBox3, gbc);

gbc.gridy = 1;

gbc.gridwidth = 3;

// Next line requires non-zero weightx value which we have above.

gbc.fill = GridBagConstraints.HORIZONTAL;

// If you don't want to use the fill constraint to extend the

// slider all the way across the top-level container you can,

// instead, set its preferred size. You can do it like this:

// Dimension d = dJSlider.getPreferredSize();

// d.width = 400;

// dJSlider.setPreferredSize(d);

jPanel1.add(dJSlider, gbc);

Container cp = getContentPane();

cp.add(drawing, "Center");

cp.add(jPanel1, "Last");

/*

GroupLayout layout = new GroupLayout(getContentPane());

getContentPane().setLayout(layout);

layout.setHorizontalGroup(

layout.createParallelGroup(GroupLayout.Alignment.LEADING)

.addComponent(jPanel1, GroupLayout.PREFERRED_SIZE,

GroupLayout.DEFAULT_SIZE, GroupLayout.PREFERRED_SIZE)

);

// Looks like you added jPanel1 above and then again below. It will

// be removed from the top and added below. You can add it only once.

layout.setVerticalGroup(

layout.createParallelGroup(GroupLayout.Alignment.LEADING)

.addComponent(jPanel1, GroupLayout.PREFERRED_SIZE,

GroupLayout.DEFAULT_SIZE, GroupLayout.PREFERRED_SIZE)

);

*/

}

private Hashtable getLabelTable(int min, int max, int inc) {

Hashtable<Integer, JLabel> table = new Hashtable<Integer, JLabel>();

for(int j = min; j <= max; j+=inc) {

String s = String.format("%.1f", (j+4)/10.0);

table.put(Integer.valueOf(j), new JLabel(s));

}

return table;

}

class Drawing extends JPanel {

// to plot lines from (x1,y1) to (x2,y2)

private double x1, y1, x2, y2;

private double lineWidth;

int a,id;

double scale;

Drawing(int a, int id, double scale) {

this.a = a;

this.id = id;

this.scale = scale;

}

public void setscale(double scale) {

this.scale = scale;

repaint();

}

public void setid(int id) {

this.id = id;

repaint();

}

public void seta(int a) {

this.a = a;

repaint();

}

public void paintComponent(Graphics g) {

super.paintComponent( g );

this.setBackground( Color.WHITE );

Graphics2D g2d = (Graphics2D)g;

g2d.drawRect(4*(int)scale+2,40*id+50,a*80+41,88);

}

}

public static void main(String[] args) {

JFrame appletFrame = new JFrame("My Applet");

JApplet theApplet = new ComboxRx2();

appletFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

appletFrame.setSize(800,600);

appletFrame.add(theApplet,"Center");

theApplet.init();

appletFrame.setVisible(true);

}

}

crwooda at 2007-7-29 12:07:51 >

As mentioned above:

// Next line requires non-zero weightx value which we have above.

//gbc.fill = GridBagConstraints.HORIZONTAL;

// If you don't want to use the fill constraint to extend the

// slider all the way across the top-level container you can,

// instead, set its preferred size. You can do it like this:

Dimension d = dJSlider.getPreferredSize();

d.width = 400;

dJSlider.setPreferredSize(d);

crwooda at 2007-7-29 12:07:51 >

jPanel1.setLayout(new GridBagLayout());

GridBagConstraints gbc = new GridBagConstraints();

// Configure constraints as you go...

gbc.insets = new Insets(2,2,2,2);

// Comment this next line out to have all column components

// clumped together in the center.

gbc.weighty = 1.0;

gbc.gridwidth = GridBagConstraints.REMAINDER;

...

jPanel1.add(jComboBox1, gbc);

...

jPanel1.add(jComboBox2, gbc);

...

jPanel1.add(jComboBox3, gbc);

...

Dimension d = dJSlider.getPreferredSize();

d.width = 250;

dJSlider.setPreferredSize(d);

jPanel1.add(dJSlider, gbc);

...

Container cp = getContentPane();

cp.add(drawing, "Center");

cp.add(jPanel1, "After");

crwooda at 2007-7-29 12:07:51 >