How to change Java code swing to change the GUI

user_14810652 0
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I found this code online and I want to change it. It is code for a calculator.

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

class Main extends JFrame implements ActionListener {
    JTextField tfield;
    double temp, temp1, result, a;
    static double m1, m2;
    int k = 1, x = 0, y = 0, z = 0;
    char ch;
    JButton b1, b2, b3, b4, b5, b6, b7, b8, b9, zero, clr, pow2, pow3, exp,
            fac, plus, min, div, log, rec, mul, eq, addSub, dot, mr, mc, mp,
            mm, sqrt, sin, cos, tan;
    Container cont;
    JPanel textPanel, buttonpanel;

    Main() {
        cont = getContentPane();
        cont.setLayout(new BorderLayout());
        JPanel textpanel = new JPanel();
        tfield = new JTextField(25);
        tfield.setHorizontalAlignment(SwingConstants.RIGHT);
        tfield.addKeyListener(new KeyAdapter() {
            public void keyTyped(KeyEvent keyevent) {
                char c = keyevent.getKeyChar();
                if (c >= '0' && c <= '9') {
                } else {
                    keyevent.consume();
                }
            }
        });
        textpanel.add(tfield);
        buttonpanel = new JPanel();
        buttonpanel.setLayout(new GridLayout(8, 4, 2, 2));
        boolean t = true;
        mr = new JButton("MR");
        buttonpanel.add(mr);
        mr.addActionListener(this);
        mc = new JButton("MC");
        buttonpanel.add(mc);
        mc.addActionListener(this);

        mp = new JButton("M+");
        buttonpanel.add(mp);
        mp.addActionListener(this);

        mm = new JButton("M-");
        buttonpanel.add(mm);
        mm.addActionListener(this);

        b1 = new JButton("1");
        buttonpanel.add(b1);
        b1.addActionListener(this);
        b2 = new JButton("2");
        buttonpanel.add(b2);
        b2.addActionListener(this);
        b3 = new JButton("3");
        buttonpanel.add(b3);
        b3.addActionListener(this);

        b4 = new JButton("4");
        buttonpanel.add(b4);
        b4.addActionListener(this);
        b5 = new JButton("5");
        buttonpanel.add(b5);
        b5.addActionListener(this);
        b6 = new JButton("6");
        buttonpanel.add(b6);
        b6.addActionListener(this);

        b7 = new JButton("7");
        buttonpanel.add(b7);
        b7.addActionListener(this);
        b8 = new JButton("8");
        buttonpanel.add(b8);
        b8.addActionListener(this);
        b9 = new JButton("9");
        buttonpanel.add(b9);
        b9.addActionListener(this);

        zero = new JButton("0");
        buttonpanel.add(zero);
        zero.addActionListener(this);

        plus = new JButton("+");
        buttonpanel.add(plus);
        plus.addActionListener(this);

        min = new JButton("-");
        buttonpanel.add(min);
        min.addActionListener(this);

        mul = new JButton("*");
        buttonpanel.add(mul);
        mul.addActionListener(this);

        div = new JButton("/");
        div.addActionListener(this);
        buttonpanel.add(div);

        addSub = new JButton("+/-");
        buttonpanel.add(addSub);
        addSub.addActionListener(this);

        dot = new JButton(".");
        buttonpanel.add(dot);
        dot.addActionListener(this);

        eq = new JButton("=");
        buttonpanel.add(eq);
        eq.addActionListener(this);

        rec = new JButton("1/x");
        buttonpanel.add(rec);
        rec.addActionListener(this);
        sqrt = new JButton("Sqrt");
        buttonpanel.add(sqrt);
        sqrt.addActionListener(this);
        log = new JButton("log");
        buttonpanel.add(log);
        log.addActionListener(this);

        sin = new JButton("SIN");
        buttonpanel.add(sin);
        sin.addActionListener(this);
        cos = new JButton("COS");
        buttonpanel.add(cos);
        cos.addActionListener(this);
        tan = new JButton("TAN");
        buttonpanel.add(tan);
        tan.addActionListener(this);
        pow2 = new JButton("x^2");
        buttonpanel.add(pow2);
        pow2.addActionListener(this);
        pow3 = new JButton("x^3");
        buttonpanel.add(pow3);
        pow3.addActionListener(this);
        exp = new JButton("Exp");
        exp.addActionListener(this);
        buttonpanel.add(exp);
        fac = new JButton("n!");
        fac.addActionListener(this);
        buttonpanel.add(fac);

        clr = new JButton("AC");
        buttonpanel.add(clr);
        clr.addActionListener(this);
        cont.add("Center", buttonpanel);
        cont.add("North", textpanel);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public void actionPerformed(ActionEvent e) {
        String s = e.getActionCommand();
        if (s.equals("1")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "1");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "1");
                z = 0;
            }
        }
        if (s.equals("2")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "2");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "2");
                z = 0;
            }
        }
        if (s.equals("3")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "3");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "3");
                z = 0;
            }
        }
        if (s.equals("4")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "4");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "4");
                z = 0;
            }
        }
        if (s.equals("5")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "5");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "5");
                z = 0;
            }
        }
        if (s.equals("6")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "6");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "6");
                z = 0;
            }
        }
        if (s.equals("7")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "7");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "7");
                z = 0;
            }
        }
        if (s.equals("8")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "8");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "8");
                z = 0;
            }
        }
        if (s.equals("9")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "9");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "9");
                z = 0;
            }
        }
        if (s.equals("0")) {
            if (z == 0) {
                tfield.setText(tfield.getText() + "0");
            } else {
                tfield.setText("");
                tfield.setText(tfield.getText() + "0");
                z = 0;
            }
        }
        if (s.equals("AC")) {
            tfield.setText("");
            x = 0;
            y = 0;
            z = 0;
        }
        if (s.equals("log")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.log(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("1/x")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = 1 / Double.parseDouble(tfield.getText());
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("Exp")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.exp(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("x^2")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.pow(Double.parseDouble(tfield.getText()), 2);
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("x^3")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.pow(Double.parseDouble(tfield.getText()), 3);
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("+/-")) {
            if (x == 0) {
                tfield.setText("-" + tfield.getText());
                x = 1;
            } else {
                tfield.setText(tfield.getText());
            }
        }
        if (s.equals(".")) {
            if (y == 0) {
                tfield.setText(tfield.getText() + ".");
                y = 1;
            } else {
                tfield.setText(tfield.getText());
            }
        }
        if (s.equals("+")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
                temp = 0;
                ch = '+';
            } else {
                temp = Double.parseDouble(tfield.getText());
                tfield.setText("");
                ch = '+';
                y = 0;
                x = 0;
            }
            tfield.requestFocus();
        }
        if (s.equals("-")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
                temp = 0;
                ch = '-';
            } else {
                x = 0;
                y = 0;
                temp = Double.parseDouble(tfield.getText());
                tfield.setText("");
                ch = '-';
            }
            tfield.requestFocus();
        }
        if (s.equals("/")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
                temp = 1;
                ch = '/';
            } else {
                x = 0;
                y = 0;
                temp = Double.parseDouble(tfield.getText());
                ch = '/';
                tfield.setText("");
            }
            tfield.requestFocus();
        }
        if (s.equals("*")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
                temp = 1;
                ch = '*';
            } else {
                x = 0;
                y = 0;
                temp = Double.parseDouble(tfield.getText());
                ch = '*';
                tfield.setText("");
            }
            tfield.requestFocus();
        }
        if (s.equals("MC")) {
            m1 = 0;
            tfield.setText("");
        }
        if (s.equals("MR")) {
            tfield.setText("");
            tfield.setText(tfield.getText() + m1);
        }
        if (s.equals("M+")) {
            if (k == 1) {
                m1 = Double.parseDouble(tfield.getText());
                k++;
            } else {
                m1 += Double.parseDouble(tfield.getText());
                tfield.setText("" + m1);
            }
        }
        if (s.equals("M-")) {
            if (k == 1) {
                m1 = Double.parseDouble(tfield.getText());
                k++;
            } else {
                m1 -= Double.parseDouble(tfield.getText());
                tfield.setText("" + m1);
            }
        }
        if (s.equals("Sqrt")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.sqrt(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("SIN")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.sin(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("COS")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.cos(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("TAN")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = Math.tan(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        if (s.equals("=")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                temp1 = Double.parseDouble(tfield.getText());
                switch (ch) {
                    case '+':
                        result = temp + temp1;
                        break;
                    case '-':
                        result = temp - temp1;
                        break;
                    case '/':
                        result = temp / temp1;
                        break;
                    case '*':
                        result = temp * temp1;
                        break;
                }
                tfield.setText("");
                tfield.setText(tfield.getText() + result);
                z = 1;
            }
        }
        if (s.equals("n!")) {
            if (tfield.getText().equals("")) {
                tfield.setText("");
            } else {
                a = fact(Double.parseDouble(tfield.getText()));
                tfield.setText("");
                tfield.setText(tfield.getText() + a);
            }
        }
        tfield.requestFocus();
    }

    double fact(double x) {
        int er = 0;
        if (x < 0) {
            er = 20;
            return 0;
        }
        double i, s = 1;
        for (i = 2; i <= x; i += 1.0)
            s *= i;
        return s;
    }

    public static void main(String args[]) {
        try {
            UIManager
                    .setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
        } catch (Exception e) {
        }
        Main f = new Main();
        f.setTitle("ScientificCalculator");
        f.pack();
        f.setVisible(true);
    }
}

while this works just fine, I want to change it a bit but am having trouble understanding the errors when I start to change this code.

I want the numbers to be in this order:

123
456
789
 0

instead of

1234
5678
90

and also to change a couple of other things but I feel like help in this may make it easy for me to understand how to change the rest.

swing java
1 Answers

The GridLayout puts each button, in the order in which you add them, in the grid. starting in the upper left corner and then to the right. If the last field in a row is reached, it goes down to the very left of the next row and proceeds.

You have to change the GridLayout from 4 columns to 3 columns. But be aware of the fact, that you still have to provide enough space for all buttons! And you have to find a place for the button "M-".

This fulfills your requirement with the order of the numbers, although you now have 11x3 fields to provide.

buttonpanel.setLayout(new GridLayout(11, 3, 2, 2));
Admin1
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