Best Method For Parent/Child Form Interaction

Question

Can anyone advise the best way to achieve the following?
* I have two forms
* Form1 creates an instance of Form2
* A user action on Form2 will affect a change on Form1
At the moment, when Form1 creates Form2, it adds an event handler to a method within Form1;
lookupFrame = new accountLookupFrame();
lookupFrame.lookupTable.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mouseClicked(java.awt.event.MouseEvent evt) {
                lookupTableMouseClicked(evt);
lookupFrame.setVisible(true);For this to work, Form2 is set for public access. Is there a better way of achieving this effect?

Answer 1

Check out my ParamDialog class (added below). In particular, check out the applyOnChange method. When this is switched on, any changes to the parameter fields will generate an apply() event (ParamDialog must be overridden to specify what happens on apply)
You should also be able to find StandardDialog by searching here; I just linked someone else to it. I think that should be all you need.
You are welcome to use and modify this code, but please do not change the package or take credit for it as your own work
ParamDialog.java
==============
package tjacobs.ui;
import java.awt.Dialog;
import java.awt.Frame;
import java.awt.GraphicsConfiguration;
import java.awt.HeadlessException;
import javax.swing.AbstractButton;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.text.Document;
import tjacobs.CollectionUtils;
//import tjacobs.OmniListener;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.InputMethodEvent;
import java.awt.event.InputMethodListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.VetoableChangeListener;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Observable;
import java.util.Observer;
import java.util.Properties;
/** Usage:
* *      ParamDialog pd = new ParamDialog(new String[] {"A", "B", "C"});
* pd.pack();
* pd.setVisible(true);
* Properties p = pd.getProperties();
public class ParamDialog extends StandardDialog {
     public static final String SECRET = "(SECRET)";
     public static final String CHECKBOX = "(CHECKBOX)";
     public static final String BUTTON = "(BUTTON)";
     public static final String BUTTON_SOLO = "(BUTTON_BOTH)";
     //public static final String BLANK = "(BLANK)";
     public static final String COMBO = "COMBO)";
     String[] fields;
     HashMap<String, GetText> mValues = new HashMap<String, GetText>();
     private boolean mShowApplyButton = false;
     //private Observable mObservable;
     //private OmniListener mOmniListener;
     private static interface GetText {
          public String getText2();
          public void setText2(String txt);
     private static class TextField extends JTextField implements GetText {
          public void setText2(String s) {
               setText(s);
          public String getText2() {
               return getText();
     private static class PasswordField extends JPasswordField implements GetText {
          public void setText2(String s) {
               setText(s);
          public String getText2() {
               return getText();
     private static class TextButton extends JButton implements GetText {
          public TextButton(String s) {
               super(s);
          public void setText2(String s) {
               setText(s);
          public String getText2() {
               return getText();
     private static class TextCheckbox extends JCheckBox implements GetText {
          public void setText2(String s) {
               setSelected("true".equals(s));
          public String getText2() {
               return "" + isSelected();
          public void _setText(String s) {
               super.setText(s);
          public String _getText() {
               return super.getText();
          public String getLabel() {
               return "";
     private static class TextCombo extends JComboBox implements GetText {
          public String getText2() {
               return getSelectedItem().toString();
          public void setText2(String str) {
               setSelectedItem(str);
     public ParamDialog(String[] fields) throws HeadlessException {
          this(null, fields);
     public ParamDialog(JFrame owner, String[] fields) {
          this (null, fields, null);
     public ParamDialog(JFrame owner, String[] fields, String[] initialValues) {
          super(owner);
          setModal(true);
          this.fields = fields;
          JPanel main = new JPanel();
          JPanel buttonP = null;
          UniversalChangeListener ucl = null;
          if (applyOnChange()) {
               ucl = new UniversalChangeListener() {
                    public void apply(AWTEvent ev) {
                         ParamDialog.this.apply();
          main.setLayout(new GridLayout(fields.length, 1));
          for (int i = 0; i < fields.length; i++) {
               JPanel con = new JPanel(new FlowLayout(FlowLayout.RIGHT));
/*               if (fields.endsWith(BLANK)) {
                    //add space filler
                    buttonP = null;
                    con.add(new Component(){
                         public Dimension getPreferredSize() {
                              return new Dimension(40, 15);
                    //con.add((Component)null);
               else
               if (fields[i].endsWith(BUTTON_SOLO)) {
                    JLabel l = new JLabel(fields[i].substring(0, fields[i].length() - BUTTON_SOLO.length()));
                    con.add(l);
                    TextButton jb = new TextButton("...");
                    //if (ucl != null) {
                    //     ucl.addComponent(jb);
                    mValues.put(fields[i], jb);
                    con.add(jb);               
               else
               if (fields[i].endsWith(BUTTON)) {
                    TextButton jb = new TextButton(fields[i].substring(0, fields[i].length() - BUTTON.length()));
                    //if (ucl != null) {
                    //     ucl.addComponent(jb);
                    mValues.put(fields[i], jb);
                    if (buttonP != null) {
                         buttonP.add(jb);
                         buttonP = null;
                         continue;
                    else {
                         con.add(jb);
                         buttonP = con;
               else {
                    buttonP = null;
                    if (fields[i].endsWith(CHECKBOX)) {
                         TextCheckbox tb = new TextCheckbox();
                         if (ucl != null) {
                              ucl.addComponent(tb);
                         con.add(new JLabel(fields[i].substring(0, fields[i].length() - CHECKBOX.length())));
                         con.add(tb);
                         //if (initialValues != null && initialValues.length > i) {
                         //     tb.setText(initialValues[i]);
                         mValues.put(fields[i], tb);
                    else if (fields[i].endsWith(COMBO)) {
                         int idx = fields[i].lastIndexOf('(');
                         if (idx == -1) {
                              throw new IllegalArgumentException(fields[i]);
                         String[] args = fields[i].substring(idx + 1, fields[i].length() - COMBO.length()).split(" ");
                         TextCombo combo = new TextCombo();
                         for (int j = 0; j < args.length; j++) {
                              combo.addItem(args[j]);
                         combo.setEditable(false);
                         fields[i] =fields[i].substring(0, idx);
                         JLabel l = new JLabel(fields[i].substring(0, idx));
                         if (ucl != null) {
                              ucl.addComponent(combo);
                         con.add(l);
                         con.add(combo);
                         //mValues.put(idx == -1 ? fields[i] : fields[i].substring(0, idx), combo);
                         mValues.put(fields[i], combo);
                    else if (fields[i].endsWith(SECRET)) {
                         PasswordField tf;
                         con.add(new JLabel(fields[i].substring(0, fields[i].length() - SECRET.length())));
                         tf = new PasswordField();
                         if (ucl != null) {
                              ucl.addComponent(tf);
                         tf.setColumns(12);
                         con.add(tf);
                         if (initialValues != null && initialValues.length > i) {
                              tf.setText(initialValues[i]);
                         mValues.put(fields[i], tf);
                    else {
                         TextField tf;
                         con.add(new JLabel(fields[i]));
                         tf = new TextField();
                         if (ucl != null) {
                              ucl.addComponent(tf);
                         tf.setColumns(12);
                         con.add(tf);
                         if (initialValues != null && initialValues.length > i) {
                              tf.setText(initialValues[i]);
                         mValues.put(fields[i], tf);
               main.add(con);               
          this.setMainContent(main);
     public Component getComponentForField(String name) {
          return (Component)mValues.get(name);
     public boolean showApplyButton() {
          return mShowApplyButton;
     public void setActionListener(String buttonName, ActionListener listener) {
          GetText gt = mValues.get(buttonName);
          if (gt instanceof AbstractButton) {
               AbstractButton ab = (AbstractButton) gt;
               ab.addActionListener(listener);
     public void apply() {
     private boolean mCancel = false;
     public void cancel() {
          mCancel = true;
          super.cancel();
     public void setField(String field, String value) {
          //JTextField tf = mValues.get(field);
          GetText tf = mValues.get(field);
          if (tf != null) {
               tf.setText2(value);
     public Properties getProperties() {
          if (mCancel) return null;
          Properties p = new Properties();
          for (int i = 0; i < fields.length; i++) {
               p.put(fields[i], mValues.get(fields[i]).getText2());
          return p;
     public void setProperties(Properties p) {
          Iterator<Object> _i= p.keySet().iterator();
          while (_i.hasNext()) {
               String key = (String) _i.next();
               String value = (String) p.get(key);
               setField(key, value);
     public void enableLoadAndSave() {
          JMenuBar bar = new JMenuBar();
          FileMenu fm = new FileMenu() {
               public void save(File f) throws IOException {
                    FileOutputStream out = new FileOutputStream(f);
                    getProperties().store(out, null);
               public void load(File f) throws IOException {
                    FileInputStream in = new FileInputStream(f);
                    Properties p = new Properties();
                    p.load(in);
                    setProperties(p);
               public boolean showSaveAs() {
                    return true;
          fm.setPrevSaveFile();
          bar.add(fm);
          setJMenuBar(bar);
     public static void main (String[] args) {
          //ParamDialog pd = new ParamDialog(new String[] {"A", "B", "C"});
          //WindowUtilities.visualize(pd);
          //Properties p = getProperties(new String[] {"A","B","C"});
          //String strs[] = new String[] {"A" + BUTTON, BLANK, "B" + CHECKBOX, "C" + SECRET, "D", "E"};
          String strs[] = new String[] {"A" + BUTTON, "Z" + BUTTON, "B" + CHECKBOX, "C" + SECRET, "D", "E", "F (A B C" + COMBO};
          String initial[] = new String[] {"A", "", "true", "pass", "", ""};
          ParamDialog pd = new ParamDialog(null, strs, initial);
          ActionListener al = new ActionListener() {
               public void actionPerformed(ActionEvent ae) {
                    System.out.println(((JButton) ae.getSource()).getLabel());
          pd.setActionListener("A" + BUTTON, al);
          pd.setActionListener("Z" + BUTTON, al);
//          pd.addObserver(new Observer() {
//               public void update(Observable o, Object obj) {
//                    System.out.println("got update");
          pd.enableLoadAndSave();
          WindowUtilities.visualize(pd);
          Properties p = pd.getProperties();
          //CollectionUtils.printCollection(p);
     public static Properties getProperties(String[] fields) {
          ParamDialog pd = new ParamDialog(fields);
          //pd.setModal(false);
          WindowUtilities.visualize(pd);
          return pd.getProperties();          
     public void setShowApplyButton(boolean b) {
          mShowApplyButton = b;
     public boolean getShowApplyButton() {
          return mShowApplyButton;
     public boolean applyOnChange() {
          return false;
     public void save(File f) throws IOException {
          FileOutputStream out = new FileOutputStream(f);
          getProperties().store(out, "params");
     public void load(File f) throws IOException {
          Properties p = new Properties();
          p.load(new FileInputStream(f));
          setProperties(p);
//     public void dispose() {
//     super.dispose();
//     Iterator _i = mValues.values().iterator();
//     while (_i.hasNext()) {
//          JComponent c = ((JComponent)_i.next());
//          //c.addPropertyChangeListener("value", listener);
//          //c.addVetoableChangeListener(listener2);
//          //c.addInputMethodListener(listener3);
//          mOmniListener.remove(c);