Answer / sriharsha gowda

public void actionPerformed(ActionEvent ae)
{
String str=ae.getActionCommand();

if(ae.getSource()==b1) setBackground(Color.yellow);
if(ae.getSource()==b2) setBackground(Color.blue);
if(ae.getSource()==b3) setBackground(Color.pink);
}
The above code can be used whenever we have different buttons and when any button is clicked its color changes accordingly

Answer / santoshi

import java.io.*;
import javax.swing.*;
import java.awt.*;
import java.awt.Color.*;
import java.event.*;
class Mypro
{
JFrame jf;
JPanel jp;
Jlabel jl;
JTextField tf;
JButton jb;
public static void main(String n[])
{
Mypro m=new Mypro();
}
public Mypro()
{
jf=new JFrame("MY own");
jp=new JPanel();
jf.add(jp);
jl=new JLabel("enter the color");
jp.add(jl);
tf=new JTextField(8);
jp.add(jf);
jb= new JButton("clikc");
jp.add(jb);
jf.setVisible(true);
jf.setSize(500,500);
}
public void actionPerformed(actionEvent ae)
{
Object o=ae.getSource();
String gt=tf.getText();
if(o==jb)
{
if(gt=="red")
setBackground(Color.red);
if(gt=="yellow")
setBackground(Color.yellow);
}
}
}

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