whats wrong with this prog?

Question

badae 0 Newbie Poster

14 Years Ago

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



 public class MenuDemo extends JApplet {



    // Text fields for Number 1, Number 2, and Result
    private JTextField jtfNum1, jtfNum2, jtfResult;

    // Buttons "Add", "Subtract", "Multiply" and "Divide"
    private JButton jbtAdd, jbtSub, jbtMul, jbtDiv;

    // Menu items "Add", "Subtract", "Multiply", "Divide" and "Close"
    private JMenuItem jmiAdd, jmiSub, jmiMul, jmiDiv, jmiClose;

    public MenuDemo() {
      // Create menu bar
      JMenuBar jmb = new JMenuBar();
      // Set menu bar to the applet
      setJMenuBar(jmb);

     // Add menu "Operation" to menu bar
      JMenu operationMenu = new JMenu("Operation");
      operationMenu.setMnemonic('O');
      jmb.add(operationMenu);

      // Add menu "Exit" to menu bar
      JMenu exitMenu = new JMenu("Exit");
      exitMenu.setMnemonic('E');
      jmb.add(exitMenu);
      // Add menu items with mnemonics to menu "Operation"
      operationMenu.add(jmiAdd= new JMenuItem("Add", 'A'));
       operationMenu.add(jmiSub = new JMenuItem("Subtract", 'S'));
       operationMenu.add(jmiMul = new JMenuItem("Multiply", 'M'));
       operationMenu.add(jmiDiv = new JMenuItem("Divide", 'D'));
       exitMenu.add(jmiClose = new JMenuItem("Close", 'C'));

       // Set keyboard accelerators
       jmiAdd.setAccelerator(
         KeyStroke.getKeyStroke(KeyEvent.VK_A, ActionEvent.CTRL_MASK));
       jmiSub.setAccelerator(
         KeyStroke.getKeyStroke(KeyEvent.VK_S, ActionEvent.CTRL_MASK));
       jmiMul.setAccelerator(
         KeyStroke.getKeyStroke(KeyEvent.VK_M, ActionEvent.CTRL_MASK));
       jmiDiv.setAccelerator(
         KeyStroke.getKeyStroke(KeyEvent.VK_D, ActionEvent.CTRL_MASK));

       // Panel p1 to hold text fields and labels
       JPanel p1 = new JPanel(new FlowLayout());
       p1.add(new JLabel("Number 1"));
       p1.add(jtfNum1 = new JTextField(3));
       p1.add(new JLabel("Number 2"));
       p1.add(jtfNum2 = new JTextField(3));
       p1.add(new JLabel("Result"));
       p1.add(jtfResult = new JTextField(4));
       jtfResult.setEditable(false);

       // Panel p2 to hold buttons
       JPanel p2 = new JPanel(new FlowLayout());
       p2.add(jbtAdd = new JButton("Add"));
       p2.add(jbtSub = new JButton("Subtract"));
       p2.add(jbtMul = new JButton("Multiply"));
       p2.add(jbtDiv = new JButton("Divide"));

       // Add panels to the frame
       setLayout(new BorderLayout());
       add(p1, BorderLayout.CENTER);
       add(p2, BorderLayout.SOUTH);

       // Register listeners
       jbtAdd.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('+');
         }
       });
     jbtSub.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('-');
         }
       });
       jbtMul.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('*');
         }
       });
       jbtDiv.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('/');
         }
       });
       jmiAdd.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('+');
         }
       });
       jmiSub.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('-');
         }
       });
       jmiMul.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('*');
         }
       });
       jmiDiv.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           calculate('/');
         }
       });
       jmiClose.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
           System.exit(0);
         }
       });
     }

     /** Calculate and show the result in jtfResult */
     private void calculate(char operator) {
       // Obtain Number 1 and Number 2
       int num1 = (Integer.parseInt(jtfNum1.getText().trim()));
       int num2 = (Integer.parseInt(jtfNum2.getText().trim()));
       int result = 0;

       // Perform selected operation
       switch (operator) {
         case '+': result = num1 + num2;
                   break;
         case '-': result = num1 - num2;
                   break;
         case '*': result = num1 * num2;
                   break;
         case '/': result = num1 / num2;
       }


       // Set result in jtfResult
      jtfResult.setText(String.valueOf(result));
     }
  }

java

Edited 11 Years Ago by mike_2000_17 because: Fixed formatting

3 Contributors
3 Replies
191 Views
2 Days Discussion Span
Latest Post 14 Years Ago Latest Post by badae

jon.kiparsky 326 Posting Virtuoso

14 Years Ago

Well, for a start, it's posted without any code tags, so it's hard to read. That's one thing that's wrong with it. For another thing, it doesn't tell me what it's supposed to do, so I can't evaluate whether the code is correct, that's a big problem.

What is the code supposed to do, and what is it doing wrong, or not doing at all?

Reply to this topic

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.

DeadSoul -2 Junior Poster in Training · Answer 1 · 2010-09-20T21:09:55+00:00

There was two mistakes there was no applet code u have specified and there was no main method declared in it i think the below code must have solved your problem

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

/*<applet>
	<applet code = MenuDemo width = 400 height = 400>
</applet>
*/

public class MenuDemo extends JApplet {



// Text fields for Number 1, Number 2, and Result
private JTextField jtfNum1, jtfNum2, jtfResult;

// Buttons "Add", "Subtract", "Multiply" and "Divide"
private JButton jbtAdd, jbtSub, jbtMul, jbtDiv;

// Menu items "Add", "Subtract", "Multiply", "Divide" and "Close"
private JMenuItem jmiAdd, jmiSub, jmiMul, jmiDiv, jmiClose;

public MenuDemo() {
// Create menu bar
JMenuBar jmb = new JMenuBar();
// Set menu bar to the applet
setJMenuBar(jmb);

// Add menu "Operation" to menu bar
JMenu operationMenu = new JMenu("Operation");
operationMenu.setMnemonic('O');
jmb.add(operationMenu);

// Add menu "Exit" to menu bar
JMenu exitMenu = new JMenu("Exit");
exitMenu.setMnemonic('E');
jmb.add(exitMenu);
// Add menu items with mnemonics to menu "Operation"
operationMenu.add(jmiAdd= new JMenuItem("Add", 'A'));
operationMenu.add(jmiSub = new JMenuItem("Subtract", 'S'));
operationMenu.add(jmiMul = new JMenuItem("Multiply", 'M'));
operationMenu.add(jmiDiv = new JMenuItem("Divide", 'D'));
exitMenu.add(jmiClose = new JMenuItem("Close", 'C'));

// Set keyboard accelerators
jmiAdd.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_A, ActionEvent.CTRL_MASK));
jmiSub.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_S, ActionEvent.CTRL_MASK));
jmiMul.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_M, ActionEvent.CTRL_MASK));
jmiDiv.setAccelerator(
KeyStroke.getKeyStroke(KeyEvent.VK_D, ActionEvent.CTRL_MASK));

// Panel p1 to hold text fields and labels
JPanel p1 = new JPanel(new FlowLayout());
p1.add(new JLabel("Number 1"));
p1.add(jtfNum1 = new JTextField(3));
p1.add(new JLabel("Number 2"));
p1.add(jtfNum2 = new JTextField(3));
p1.add(new JLabel("Result"));
p1.add(jtfResult = new JTextField(4));
jtfResult.setEditable(false);

// Panel p2 to hold buttons
JPanel p2 = new JPanel(new FlowLayout());
p2.add(jbtAdd = new JButton("Add"));
p2.add(jbtSub = new JButton("Subtract"));
p2.add(jbtMul = new JButton("Multiply"));
p2.add(jbtDiv = new JButton("Divide"));

// Add panels to the frame
setLayout(new BorderLayout());
add(p1, BorderLayout.CENTER);
add(p2, BorderLayout.SOUTH);

// Register listeners
jbtAdd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('+');
}
});
jbtSub.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('-');
}
});
jbtMul.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('*');
}
});
jbtDiv.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('/');
}
});
jmiAdd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('+');
}
});
jmiSub.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('-');
}
});
jmiMul.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('*');
}
});
jmiDiv.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
calculate('/');
}
});
jmiClose.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
});
}

/** Calculate and show the result in jtfResult */
private void calculate(char operator) {
// Obtain Number 1 and Number 2
int num1 = (Integer.parseInt(jtfNum1.getText().trim()));
int num2 = (Integer.parseInt(jtfNum2.getText().trim()));
int result = 0;

// Perform selected operation
switch (operator) {
case '+': result = num1 + num2;
break;
case '-': result = num1 - num2;
break;
case '*': result = num1 * num2;
break;
case '/': result = num1 / num2;
}


// Set result in jtfResult
jtfResult.setText(String.valueOf(result));
}
public static void main()
{
MenuDemo m1 = new MenuDemo();
}
}

if this thread is solved then mark it as solved.
ok

badae 0 Newbie Poster · Answer 2 · 2010-09-22T08:59:02+00:00

thanks for the reply...i was able to run this program... thank you.....