Name: joT67522 Date: 09/15/97


An extended Dialog class cannot correctly set value given TextCompoent.

(** Step 1 **) Run: java ChoiceDialog
(** Step 2 **) Source codes

An extened Dialog, myDialog, implements ActionListener cannot
correctly set value to a TextComponent passed in at the class
construction.

The value at example 1 of the item.getText()
didn't return correct answer all the time.

Example 2 use method to catch value change, it failed too.
BUT if I reuse the object, the value changed correctly.

//
// EXAMPLE 1
//
import java.awt.*;
import java.awt.event.*;

public class AcceptDialog implements ActionListener
{
   public static void main(String args[]) {
      Frame f = new Frame();
      TextField item = new TextField();
      f.setTitle("Function Counting Analyze");
      f.setSize(300,300);
      f.pack();
      f.show();
      AcceptDialog ad = new AcceptDialog( f, "Input your choice"
                  , "What is the answer of\nFlag is flying in the deep
sea\n?????\n", item );
      System.out.println("Answer is " + item.getText() );
      System.exit(0);
   } // main

   protected Frame f;
   protected Dialog dl;
   protected MultiLineLabel mLabel;
   protected Button acceptButton, cancelButton;
   protected boolean acceptAndExit;
   protected TextField acceptField;
   protected StatusConsol sc;

   public AcceptDialog( Frame parent, String title, String message, TextField af
){
      this(parent, title, message, af, (StatusConsol)null, true );
   }
   public AcceptDialog( Frame parent, String title, String message
                      , TextField af, StatusConsol sc ) {
      this(parent, title, message, af, sc, true );
   }
   public AcceptDialog( Frame parent, String title, String message, TextField af
                      , StatusConsol sc, boolean acceptAndExit ){
      // create the window
      dl = new Dialog(f = parent, title, true);
      this.sc = sc;
      this.acceptAndExit = acceptAndExit;

      dl.setLayout(new BorderLayout());
      mLabel = new MultiLineLabel(message);
      dl.add( mLabel, "Center");

      Panel fp = new Panel(new GridLayout(2,1));
      Panel p = new Panel();
      acceptField = af;
      acceptField.setColumns(32);
      p.add(acceptField);
      acceptField.addActionListener(this);
      fp.add(p);
      p = new Panel();
      p.add(acceptButton = new Button("ACCEPT"));
      acceptButton.addActionListener(this);
      p.add(cancelButton = new Button("CANCEL"));
      cancelButton.addActionListener(this);
      fp.add(p);
      dl.add( fp, "South" );

      dl.pack();
      dl.show();
   }

   protected void output( String msg ) {
      if ( this.sc == null )
         System.out.println( msg );
      else
         sc.sendMessage( msg );
   }

//
// Implementation of ActionListener Interface
//
   public void actionPerformed(ActionEvent event)
   {
      Object target = event.getSource();

      if ( target == acceptField ) {
         output(acceptField.getText() + " Enterred.");
         if ( acceptAndExit ) {
            dl.dispose();
         }
      } else if ( target == acceptButton ) {
         output("Accept.");
         dl.dispose();
      } else if ( target == cancelButton ) {
         output("Cancelled.");
         acceptField.setText("");
         dl.dispose();
      }
   } // actionPerformed()
} // class AcceptDialog
 
//
// Example 2 -- YesNoDialog
//
import java.awt.*;
import java.awt.event.*;

public class YesNoDialog extends Dialog
   implements ActionListener
{
   protected Frame f;
   protected MultiLineLabel mLabel;
   protected Button yesButton, noButton;
   protected boolean acceptAndExit;
   protected StatusConsol sc;

   public YesNoDialog( Frame parent, String title, String message ){
      this(parent, title, message, (StatusConsol)null);
   }
   public YesNoDialog( Frame parent, String title, String message, StatusConsol
sc ) {
      // create the window
      super(parent, title, true);
      this.sc = sc;

      this.setLayout(new BorderLayout());
      mLabel = new MultiLineLabel(message);
      add( mLabel, "Center");
      Panel p = new Panel();
      p.add(yesButton = new Button("YES"));
      yesButton.addActionListener(this);
      p.add(noButton = new Button("NO"));
      noButton.addActionListener(this);
      add( p, "South" );
      // addWindowListener(this); // want window events
      pack();
      show();
   }

   public void showAgain() { pack(); show(); }

   private void output( String msg ) {
      if ( this.sc == null )
         System.out.println( msg );
      else
         sc.sendMessage( msg );
   }
   protected void winEventMsg( String who, WindowEvent event) {
      // output("Dialog (" + who + ") - " + event.toString());
   }

   public void yes() { output("YES pushed");}
   public void no() { output("NO pushed");}
//
// Implementation of ActionListener Interface
//
   public void actionPerformed(ActionEvent event)
   {
      Object target = event.getSource();

      if ( target == yesButton ) {
         yes();
         dispose();
      } else if ( target == noButton ) {
         no();
         dispose();
      }
   } // actionPerformed()
} // class YesNoDialog

//
// Example 2: ChoiceDialog -- main method is here
//

import java.awt.*;

public class ChoiceDialog extends YesNoDialog {
      public static void main(String args[]) {
         Frame f = new Frame();
         f.setTitle("YES & NO Dialog");
         f.setSize(300,300);
         f.pack();
         f.show();
         ChoiceDialog ad = new ChoiceDialog( f, "Make a Choice"
                  , "What is the answer of\nFlag is flying in the deep
sea\n?????\n" );
         System.out.println("Answer is " + ad.getAnswer() );
         ad = new ChoiceDialog( f, "mm", "Make a choice" );
         System.out.println("Answer is " + ad.getAnswer() );
         for(int ix=0; ix < 10; ix++) {
            ad.showAgain(); // now it work. ??? WHY ???
            System.out.println("Answer is " + ad.getAnswer() );
         }
         System.exit(0);
      } // main
  
      private int answerX;
      static int cnt = 0;
      public ChoiceDialog( Frame f, String title, String msg ) {
         super(f, title, msg);
         answerX = -99;
      }
      private void output(String msg) {
         System.out.println(msg + answerX + " @(" + (++cnt) + ")" );
      }
      public void yes() { answerX = 1; output("choice answer = "); }
      public void no() { answerX = 0; output("choice answer = ");}
      synchronized public int getAnswer() {
         output("Choice has answer of ");
         return answerX;
         }
}
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