please help...frame based application error

[chandan kuchipudi]

hi ......i'm very new to java...i'm learning core java for 2 months....i'm getting errors while devoloping a frame based checkbox application ....please look into that and help me to devolope that ...


here is the program

//CbDemo.java
import java.awt.*;
import java.awt.event.*;
class Cb extends Frame
{
Checkbox cb1;
Label l1,l2;
Cb()
{
setTitle("checkbox example");
setSize(200,200);
FlowLayout fl=new FlowLayout();
setLayout(fl);


// create the components

cb1=new Checkbox("java");
l1=new Label("select the course");
l2=new Label();

// add components to container

add(l1);add(cb1);add(l2);

// registration

Sathya so=new Sathya();
cb1.addItemListener(so);
setVisible(true);

}//cb ()

class Sathya implements ItemListener

{
public void ItemStateChanged(ItemEvent ie)
{
if(ie.getSource()==cb1)
{
if(cb1.getState())
{
l2.setText("your selected course:"+cb1.getLabel());
}
else
{
l2.setText("please select a course");
}
}//if
}//isc
}//sathya
}//cb
class CbDemo
{
public static void main (String []args)
{
Cb co=new Cb();
}
}






//it is showing that line no. 34 is an error ....

line no.34 : class Sathya implements ItemListener



Cb.Sathya is not abstract method and does not override abstract method ItemStateChanged(ItemEvent) in ItemListener

please let me know what is wrong in that .....thank you ..

[Julien Coe]

class Sathya implements ItemListener
	{
		public void ItemStateChanged(ItemEvent ie)
		{} 
	}

is not the same as :

class Sathya implements ItemListener
	{
		public void itemStateChanged(ItemEvent e)
		{}
	}

itemStateChanged starts with a little 'i'

[chandan kuchipudi]

thank you julien coe .....i've changed "i" .....but still it is showing error like this

line no 53 error : Cb is abstract;cannot be instantiated...

Cb co =new Cb();


i've written it as a part of execution logic class....please look it once...

[Julien Coe]

This is your code with some formatting

import java.awt.*;
import java.awt.event.*;

class Cb extends Frame
{
	Checkbox	cb1;
	Label		l1, l2;

	Cb()
	{
		setTitle("checkbox example");
		setSize(200, 200);
		FlowLayout fl = new FlowLayout();
		setLayout(fl);

		// create the components

		cb1 = new Checkbox("java");
		l1 = new Label("select the course");
		l2 = new Label();

		// add components to container

		add(l1);
		add(cb1);
		add(l2);

		// registration

		Sathya so = new Sathya();
		cb1.addItemListener(so);
		setVisible(true);

	}// cb ()

	class Sathya implements ItemListener
	{
		public void itemStateChanged(ItemEvent e)
		{
			if(e.getSource() == cb1)
			{
				if(cb1.getState())
				{
					l2.setText("your selected course:" + cb1.getLabel());
				}
				else
				{
					l2.setText("please select a course");
				}
			}// if
		}
	}// sathya
}// cb

public class CbDemo
{
	public static void main(String[] args)
	{
		Cb co = new Cb();
	}
}

But when I write it in my IDE, no error's showing. So, it's probably something else.