Create a class called ComboPanel that extends JPanel. The class constructor shou

Question

Create a class called ComboPanel that extends JPanel. The class constructor should add three JComboBox objects to the panel and initialize each of them with Integer objects with values that range from 0 to 255. Each JComboBox will allow the user to select an integer for the three components (red, green, and blue) that make up a Color object. For example, invoking new Color(255, 215, 0) creates a yellowish color object.

Create listener objects for each JComboBox that set the background color of the panel when the user selects an integer. Use the current values supplied by the JComboBox objects to determine the background color.

Use the following code to test your class.

Explanation / Answer

DO Rate if satisfied

import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JComboBox;
import javax.swing.JPanel;

public class ComboPanel extends JPanel implements ActionListener{
JComboBox red;
JComboBox blue;
JComboBox green;
  
ComboPanel(){
Integer intlist [] = new Integer[256];
for(int i=0; i< 256; i++)
intlist[i] = new Integer(i);
red = new JComboBox(intlist);
blue = new JComboBox(intlist);
green = new JComboBox(intlist);
this.add(red);
this.add(blue);
this.add(green);
red.addActionListener(this);
green.addActionListener(this);
blue.addActionListener(this);
this.validate();
}

@Override
public void actionPerformed(ActionEvent e) {
int r = ((Integer)red.getSelectedItem()).intValue();
int g = ((Integer)green.getSelectedItem()).intValue();
int b = ((Integer)blue.getSelectedItem()).intValue();
  
this.setBackground(new Color(r, g, b));
this.validate();
}
  
}

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