ClassCastException: sun.plugin.viewer.frame.IExplorerEmbeddedFrame to ViewerFrame

[Mohiuddin Russel]

When i am going to run my swing application as a applet, it shows an error ClassCastException: sun.plugin.viewer.frame.IExplorerEmbeddedFrame to ViewerFrame. ViewerFrame is a class that is inherited from JFrame. If i run it as a standalone swing application then it runs well. After some debugging i found that when the program run as an applet in the browser, viewer class name changes to IExplorerEmbeddedFrame. Please help me what i have to do? Thanks in advance.

[Matt Cartwright]

Howdy Mohiuddin and welcome to the Ranch

when you say

going to run my swing application as a applet

does that mean you are using the appletviewer?

If that is a yes, your code should be something like:

    

import java.applet.Applet;
import java.awt.Graphics;


public class MyApplet extends Applet
{

   private static final long serialVersionUID = 2036409617878214499L;

   private String            string           = null;


   public void init()
   {
      string = "This is my first applet";
   }

   public void paint( Graphics g )
   {
      g.drawString(string, 50, 50);
   }
}

Hope that helps
Matt

[Rob Spoor]

Applets don't use user implemented frames. Instead there is a Frame (not JFrame!) representation of the browser window. The applet is added to this frame.

To run a Swing application as an applet, you need to do the following:
- take away all logic from the frame class, and put it in one (or more) other class(es).
- the frame just adds all components from that (those) other class(es).
- the applet does the same

A very brief:

class ContentPanel extends JPanel
{
    // add all UI code here
}

class MyFrame extends JFrame
{
    public MyFrame()
    {
        add(new ContentPanel());
    }
}

class MyApplet extends JApplet
{
    public MyApplet()
    {
        add(new ContentPanel());
    }
}

[Mohiuddin Russel]

Thank You very much for your help.

It works now.

[Rob Spoor]

You're welcome.