Assignment-2

-
 import java.awt.*;
import java.awt.event.*;
public class Prac2 implements ItemListener {
    Frame f;
    Checkbox c1,c2,c3;
    Canvas c;
    int red=0,blue=0,green=0;
    Prac2()
    {
        f=new Frame("Practical-8");
        c1=new Checkbox("Red");
        c2=new Checkbox("Green");
        c3=new Checkbox("Blue");
        
        c1.addItemListener(this);
        c2.addItemListener(this);
        c3.addItemListener(this);
        
        c=new Canvas();
        c.setSize(30,30);
        c.setBackground(Color.BLACK);
   
        f.setLayout(new FlowLayout());
        
        f.add(c1);
        f.add(c2);
        f.add(c3);
        f.add(c);
        
        f.setSize(300,300);
        f.setVisible(true);
    }
    
    public static void main(String[] args)
    {
        Prac2 f=new Prac2();
    }
    public void itemStateChanged(ItemEvent e)
    {
        if(c1.getState())
            red=255;
        else
            red=0;
        if(c2.getState())
            green=255;
        else
            green=0;
        if(c3.getState())
            blue=255;
        else
       blue=0;
      Color clr=new Color(red,green,blue);
      c.setBackground(clr);
    }
}

Output:-





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