Question

any help please

using Swing GUI, which simulates a calculator.

Answer 1

import javax.swing.*;

import java.awt.event.*;

class Calc implements ActionListener

{

    JFrame f;

    JTextField t;

    JButton b1,b2,b3,b4,b5,b6,b7,b8,b9,b0,bdiv,bmul,bsub,badd,bdec,beq,bdel,bclr;

    static double a=0,b=0,result=0;

    static int operator=0;

    Calc()

    {

        f=new JFrame("Calculator");

        t=new JTextField();

        b1=new JButton("1");

        b2=new JButton("2");

        b3=new JButton("3");

        b4=new JButton("4");

        b5=new JButton("5");

        b6=new JButton("6");

        b7=new JButton("7");

        b8=new JButton("8");

        b9=new JButton("9");

        b0=new JButton("0");

        bdiv=new JButton("/");

        bmul=new JButton("*");

        bsub=new JButton("-");

        badd=new JButton("+");

        bdec=new JButton(".");

        beq=new JButton("=");

        bdel=new JButton("Delete");

        bclr=new JButton("Clear");

        

        t.setBounds(30,40,280,30);

        b7.setBounds(40,100,50,40);

        b8.setBounds(110,100,50,40);

        b9.setBounds(180,100,50,40);

        bdiv.setBounds(250,100,50,40);

        

        b4.setBounds(40,170,50,40);

        b5.setBounds(110,170,50,40);

        b6.setBounds(180,170,50,40);

        bmul.setBounds(250,170,50,40);

        

        b1.setBounds(40,240,50,40);

        b2.setBounds(110,240,50,40);

        b3.setBounds(180,240,50,40);

        bsub.setBounds(250,240,50,40);

        

        bdec.setBounds(40,310,50,40);

        b0.setBounds(110,310,50,40);

        beq.setBounds(180,310,50,40);

        badd.setBounds(250,310,50,40);

        

        bdel.setBounds(60,380,100,40);

        bclr.setBounds(180,380,100,40);

        

        f.add(t);

        f.add(b7);

        f.add(b8);

        f.add(b9);

        f.add(bdiv);

        f.add(b4);

        f.add(b5);

        f.add(b6);

        f.add(bmul);

        f.add(b1);

        f.add(b2);

        f.add(b3);

        f.add(bsub);

        f.add(bdec);

        f.add(b0);

        f.add(beq);

        f.add(badd);

        f.add(bdel);

        f.add(bclr);

        

        f.setLayout(null);

        f.setVisible(true);

        f.setSize(350,500);

        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        f.setResizable(false);

        

        b1.addActionListener(this);

        b2.addActionListener(this);

        b3.addActionListener(this);

        b4.addActionListener(this);

        b5.addActionListener(this);

        b6.addActionListener(this);

        b7.addActionListener(this);

        b8.addActionListener(this);

        b9.addActionListener(this);

        b0.addActionListener(this);

        badd.addActionListener(this);

        bdiv.addActionListener(this);

        bmul.addActionListener(this);

        bsub.addActionListener(this);

        bdec.addActionListener(this);

        beq.addActionListener(this);

        bdel.addActionListener(this);

        bclr.addActionListener(this);

    }

    public void actionPerformed(ActionEvent e)

    {

        if(e.getSource()==b1)

            t.setText(t.getText().concat("1"));

        

        if(e.getSource()==b2)

            t.setText(t.getText().concat("2"));

        

        if(e.getSource()==b3)

            t.setText(t.getText().concat("3"));

        

        if(e.getSource()==b4)

            t.setText(t.getText().concat("4"));

        

        if(e.getSource()==b5)

            t.setText(t.getText().concat("5"));

        

        if(e.getSource()==b6)

            t.setText(t.getText().concat("6"));

        

        if(e.getSource()==b7)

            t.setText(t.getText().concat("7"));

        

        if(e.getSource()==b8)

            t.setText(t.getText().concat("8"));

        

        if(e.getSource()==b9)

            t.setText(t.getText().concat("9"));

        

        if(e.getSource()==b0)

            t.setText(t.getText().concat("0"));

        

        if(e.getSource()==bdec)

            t.setText(t.getText().concat("."));

        

        if(e.getSource()==badd)

        {

            a=Double.parseDouble(t.getText());

            operator=1;

            t.setText("");

        }

        

        if(e.getSource()==bsub)

        {

            a=Double.parseDouble(t.getText());

            operator=2;

            t.setText("");

        }

        

        if(e.getSource()==bmul)

        {

            a=Double.parseDouble(t.getText());

            operator=3;

            t.setText("");

        }

        

        if(e.getSource()==bdiv)

        {

            a=Double.parseDouble(t.getText());

            operator=4;

            t.setText("");

        }

        

        if(e.getSource()==beq)

        {

            b=Double.parseDouble(t.getText());

        

            switch(operator)

            {

                case 1: result=a+b;

                    break;

        

                case 2: result=a-b;

                    break;

        

                case 3: result=a*b;

                    break;

        

                case 4: result=a/b;

                    break;

        

                default: result=0;

            }

        

            t.setText(""+result);

        }

        

        if(e.getSource()==bclr)

            t.setText("");

        

        if(e.getSource()==bdel)

        {

            String s=t.getText();

            t.setText("");

            for(int i=0;i<s.length()-1;i++)

            t.setText(t.getText()+s.charAt(i));

        }        

    }

    public static void main(String...s)

    {

        new Calc();

    }

}