Java calculator app

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Calculator implements ActionListener{

JFrame frame;
JTextField textfield;
JButton[] numberButtons = new JButton[10];
JButton[] functionButtons = new JButton[9];
JButton addButton,subButton,mulButton,divButton;
JButton decButton, equButton, delButton, clrButton, negButton;
JPanel panel;

Font myFont = new Font("Ink Free",Font.BOLD,30);

double num1=0,num2=0,result=0;
char operator;

Calculator(){

frame = new JFrame("Calculator");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(420, 550);
frame.setLayout(null);

textfield = new JTextField();
textfield.setBounds(50, 25, 300, 50);
textfield.setFont(myFont);
textfield.setEditable(false);

addButton = new JButton("+");
subButton = new JButton("-");
mulButton = new JButton("*");
divButton = new JButton("/");
decButton = new JButton(".");
equButton = new JButton("=");
delButton = new JButton("Del");
clrButton = new JButton("Clr");
negButton = new JButton("(-)");

functionButtons[0] = addButton;
functionButtons[1] = subButton;
functionButtons[2] = mulButton;
functionButtons[3] = divButton;
functionButtons[4] = decButton;
functionButtons[5] = equButton;
functionButtons[6] = delButton;
functionButtons[7] = clrButton;
functionButtons[8] = negButton;

for(int i =0;i<9;i++) {
functionButtons[i].addActionListener(this);
functionButtons[i].setFont(myFont);
functionButtons[i].setFocusable(false);
}

for(int i =0;i<10;i++) {
numberButtons[i] = new JButton(String.valueOf(i));
numberButtons[i].addActionListener(this);
numberButtons[i].setFont(myFont);
numberButtons[i].setFocusable(false);
}

negButton.setBounds(50,430,100,50);
delButton.setBounds(150,430,100,50);
clrButton.setBounds(250,430,100,50);

panel = new JPanel();
panel.setBounds(50, 100, 300, 300);
panel.setLayout(new GridLayout(4,4,10,10));

panel.add(numberButtons[1]);
panel.add(numberButtons[2]);
panel.add(numberButtons[3]);
panel.add(addButton);
panel.add(numberButtons[4]);
panel.add(numberButtons[5]);
panel.add(numberButtons[6]);
panel.add(subButton);
panel.add(numberButtons[7]);
panel.add(numberButtons[8]);
panel.add(numberButtons[9]);
panel.add(mulButton);
panel.add(decButton);
panel.add(numberButtons[0]);
panel.add(equButton);
panel.add(divButton);

frame.add(panel);
frame.add(negButton);
frame.add(delButton);
frame.add(clrButton);
frame.add(textfield);
frame.setVisible(true);
}

public static void main(String[] args) {

Calculator calc = new Calculator();
}

@Override
public void actionPerformed(ActionEvent e) {

for(int i=0;i<10;i++) {
if(e.getSource() == numberButtons[i]) {
textfield.setText(textfield.getText().concat(String.valueOf(i)));
}
}
if(e.getSource()==decButton) {
textfield.setText(textfield.getText().concat("."));
}
if(e.getSource()==addButton) {
num1 = Double.parseDouble(textfield.getText());
operator ='+';
textfield.setText("");
}
if(e.getSource()==subButton) {
num1 = Double.parseDouble(textfield.getText());
operator ='-';
textfield.setText("");
}
if(e.getSource()==mulButton) {
num1 = Double.parseDouble(textfield.getText());
operator ='*';
textfield.setText("");
}
if(e.getSource()==divButton) {
num1 = Double.parseDouble(textfield.getText());
operator ='/';
textfield.setText("");
}
if(e.getSource()==equButton) {
num2=Double.parseDouble(textfield.getText());

switch(operator) {
case'+':
result=num1+num2;
break;
case'-':
result=num1-num2;
break;
case'*':
result=num1*num2;
break;
case'/':
result=num1/num2;
break;
}
textfield.setText(String.valueOf(result));
num1=result;
}
if(e.getSource()==clrButton) {
textfield.setText("");
}
if(e.getSource()==delButton) {
String string = textfield.getText();
textfield.setText("");
for(int i=0;i<string.length()-1;i++) {
textfield.setText(textfield.getText()+string.charAt(i));
}
}
if(e.getSource()==negButton) {
double temp = Double.parseDouble(textfield.getText());
temp*=-1;
textfield.setText(String.valueOf(temp));
}
}
}

great

This was indeed Helpful brother
Thanks for the tutorial

Thank You ❤

Amazing!

Very cool! Helped me alot!

the decbutton button is reapting can you make one time

Thanks a lot bro. I already made it

ActionListener not work

Thanks!!!

what pulgin should I first install to build the calculator????

God when😢

why did you implement constructor

can you change the color of the calculator?

thank you

How do you run your program even if you are not finish with the code? I was following your code then my application wont run because of error. I was checking the design output

it can count for single digit how can we use for double or more digit?

Nice

u can add this also to prevent adding more than one decimal point
if (e.getSource() == decButton) {
//programming the decimal buttons

String temp = textField.getText();
if (!temp.contains(".")) {
//preventing adding more than one cecimal
textField.setText(temp + ".");
}

}

guds

Thanks
Wonderful video ! This video is easy to understand and very helpful.

Your amazing Content makes me to passionate about java more...
I thought to left but ...

Thanks legend🫡💪

Dear Bro you are simply amazing... ❤❤💐💐being sooo... generous in sharing your wealth of knowledge and you certainly deserve a very big appreciation for making me impressed to learn Java programming. God Bless You Bro...🙏🙏. I really loved it and impatient to try it ASAP..... 👌👌👍👍

Best code

man Thank you i really need this tutorial for my computer programming 2

mines working but the result is not correct
how do I fix it?

thanks bro

such are the people who are not stingy.

thanks.

God of Java this guy💯💯❤️🤞

Great, fantastic. It may seem a little but too advanced at the beginning, but you can try it and see:)

We need to click the equal button between the operation like 1+2=3+2=5
How can solve it click equal button between 2 operations

thanks a lot , but why when i used for loop for focButton , it didn't work ;

thanks for the video.
for the decimal point button, i added a little bit of if statement to prevent the program from adding more dots to the textfield:
if(e.getSource()==decButton)
{
String myString = textfield.getText();
if (!myString.contains(".")) { // Check if there is no dot already present
textfield.setText(textfield.getText().concat("."));
}

}

<3

Bro pls... Send the full program code to help ful others to do project... Copy to paste

vajco

thanks for clean work it really help me !you are super good :)

Great tutorial, thank you.

This is an amazing tutorial, thumbs up. I would have loved to see how you handled division by 0. I have also noticed that its possible to have multiple dots in a number which would result in an error during calculations.

I just begun with Java and made my own calculator like this. But after finishing and seeing this video, there is a lot of things I could do to definetly reduce my code size.

I followed through this whole tutorial on Linux with text editor and terminal Javac compiling (no IDE!) and it worked flawlessly even when packaged into a jar file. I feel like I learned stuff but even if I didn’t, I at least understand how the program works and it was fun to feel like I’m coding stuff just by following along

Thanks man

Thank you very much

nice :)