A Java Program to make a simple calculator.

Hey Guys!!! Welcome once again.It's  Parth here.In this tutorial we are going to make a simple calculator which can perform addition,subtraction,multiplication,and division operation.For that you need 4 buttons,2 text field to insert input to the calc and a label to print the calculated input.I have used grid layout of 4X4.Here i have used the pannel of 300px X 300px, you can use your own size.

Let's start to program the calculator.

import java.awt.*;

import java.awt.event.*;

class MyFrame extends Frame implements ActionListener

{

            Button b1,b2,b3,b4;

            TextField t,tx;

            Label l;

            int n;

MyFrame()

            {

                       

                        t = new TextField(10);

                        tx = new TextField(10);

                        b1= new Button("+");

                        b2= new Button("-");

                        b3= new Button("*");

                        b4= new Button("/");

                        l = new Label("Ans");

                        setLayout(new GridLayout(4,4));

                       

                        add(t);

                        add(tx);                       

                        add(b1);

                        add(b2);

                        add(b3);

                        add(b4);

add(l);

                       

b1.addActionListener(this);

                        b2.addActionListener(this);

                        b3.addActionListener(this);

                        b4.addActionListener(this);

}

public void actionPerformed(ActionEvent e)

            {           String a=t.getText();

                        int n1=Integer.parseInt(a);

                        String b=tx.getText();

                        int n2=Integer.parseInt(a);

                        String s=e.getActionCommand();

                       

                        if(s.equals("+"))

                        {

                                    n=n1+n2;

                        }

                        else if(s.equals("-"))

                        {

                                    n=n1-n2;

                        }

                        else if(s.equals("*"))

                        {

                                    n=n1*n2;

                        }

                        else if(s.equals("/"))

                        {

                                    n=n1/n2;

                        }                      

l.setText(n+" ");

}

}

class Demo

{

            public static void main(String args[])

            {          

                        MyFrame a=new MyFrame();

                        a.setSize(300,300);

                        a.setVisible(true);

            }

}

Output of this program is same as the above image.If you have any query comment below.