Having alot of trouble with using java graphics jframe and action listeners. Thi

Question

Having alot of trouble with using java graphics jframe and action listeners.

This calculator must look like the one above and use jframe, buttons , actionlistener ect. Use flowlayout and borderlayout.

only need to do + - * /

The basic principle is

1: Get a number from user

2: check to see if a opporator is selected. If so clear the text box and get the next number.

3: Then execute the opporation if the equal sign is selected or another opporator is selected and display the results .

4: if opporator is already selected display messege.

My calculator 78.0 clear Can't choose an operator again! Create a calculator like the above visual. The clear button resets the calculator. The label will display a warning if the user picks an operator right after an operator has already been picked. The calculator should be fully functioning.

Explanation / Answer

//Calc.java

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");
  
b7.setBounds(40,100,50,40);
b8.setBounds(110,100,50,40);
b9.setBounds(180,100,50,40);
badd.setBounds(250,100,50,40);
  
b4.setBounds(40,170,50,40);
b5.setBounds(110,170,50,40);
b6.setBounds(180,170,50,40);
bsub.setBounds(250,170,50,40);
  
b1.setBounds(40,240,50,40);
b2.setBounds(110,240,50,40);
b3.setBounds(180,240,50,40);
bmul.setBounds(250,240,50,40);
  
bdec.setBounds(40,310,50,40);
b0.setBounds(110,310,50,40);
beq.setBounds(180,310,50,40);
bdiv.setBounds(250,310,50,40);
  
t.setBounds(30,380,200,30);
bclr.setBounds(240,380,80,40);
  
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();
}
}

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.