Question

I am trying to convert a working simple Java application to an applet. The application consists of a main.java and a gooey.java

Main.java

package hellow_convert;
import javax.swing.JApplet;
public class main extends JApplet {
public static void main(String[] args) {
gooey gui = new gooey();    
}
public void init() 
{ 
gooey gui = new gooey();        
} 
public void stop() {}
}

gooey.java

package hellow_convert;
import javax.swing.*;
import java.util.*;
import java.awt.*;
public class gooey {    
public  JFrame f = new JFrame();
private JPanel pnlNorth = new JPanel(); 
private JButton btnNorth = new JButton("North");
private JMenuBar mb = new JMenuBar(); // MenuBar
private JMenu mnuFile = new JMenu("File"); // File Entry on Menu bar
private JMenuItem mnuItemAbout = new JMenuItem("About"); // About Entry
public gooey(){
f.setJMenuBar(mb);
mb.add(mnuFile);       
mb.add(mnuHelp);
pnlNorth.add(btnNorth);
f.getContentPane().setLayout(new BorderLayout());
f.getContentPane().add(pnlNorth, BorderLayout.NORTH);
f.setBounds(100, 100, 200, 100);
}
}

It looks like this.

I just cant seem to make it run as an applet. When I run it in debug, an applet window opens, and then, the JFrame window pops up (just as in the application). As an application, it runs as expected, but how do I get controls into the Applet window?
I’m new to this. Any help is appreciated!

Answer 1

Well, JApplet is a Swing container itself and thus you’d have to use the applet’s content pane in your class gooey, instead of always using a JFrame (which is a desktop window and wouldn’t not work with an applet).

Try and pass either the JApplet or the JFrame to the gooey() constructor, instead of creating the JFrame in that class.

Edit: your constructor might look like this:

public gooey(RootPaneContainer c){
  c.getRootPane().setJMenuBar(mb);
  mb.add(mnuFile);       
  mb.add(mnuHelp);
  pnlNorth.add(btnNorth);
  c.getContentPane().setLayout(new BorderLayout());
  c.getContentPane().add(pnlNorth, BorderLayout.NORTH);      

}

Then call it like:

JFrame f = new JFrame(...);
new gooey(f);

or

JApplet a = new JApplet(...);        
new gooey(a);

you could also do this in your main class, since it is already an applet instance

new gooey(this);

The setBounds(...) should only be called when dealing with a JFrame.