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Groups > comp.lang.java.programmer > #27119

Re: "cannot find symbol" on menuItem for ActionListener

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When yall do that, in order to call the objects into an action listener, initially set the objects as public before the main. When doing this, there is no need to instantiate the variables.


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

public class MainFrame extends JPanel implements ActionListener {
    private JButton displayButton;
    private JButton findButton;
    private JButton addButton;
    public JTextArea displayWords;
    public JMenuBar menuBar;
    public JTextField wordInput;
    public JTextField inputWord;
    public JLabel mpLabel;
    public JButton deleteButton;
public JMenu fileMenu;
public  JMenuItem exitItem;
public JMenuItem loadItem 
public JMenu configureMenu;
public JMenuItem setwordsItem;  
public JMenu helpMenu;
JMenuItem contentsItem 
    public MainFrame()
    {
        fileMenu = new JMenu ("File");
       exitItem = new JMenuItem ("Exit");
        loadItem = new JMenuItem ("Load");
         configureMenu = new JMenu ("Configure");
       setwordsItem = new JMenuItem ("Set number of
words");
       helpMenu = new JMenu ("Help");
        JMenuItem contentsItem = new JMenuItem ("Contents");
        JMenuItem aboutItem = new JMenuItem ("About");

        fileMenu.add (loadItem);
        fileMenu.add (exitItem);
        configureMenu.add (setwordsItem);
        helpMenu.add (aboutItem);
        helpMenu.add (contentsItem);

        displayButton = new JButton ("Display Words");
        findButton = new JButton ("Find");
        addButton = new JButton ("Add");
        displayWords = new JTextArea (5, 5);
        menuBar = new JMenuBar();
        menuBar.add (fileMenu);
        menuBar.add (configureMenu);
        menuBar.add (helpMenu);
        wordInput = new JTextField (6);
        inputWord = new JTextField (5);
        mpLabel = new JLabel ("E-Dictionary v1.0");
        deleteButton = new JButton ("Delete");

        displayButton.setToolTipText ("Display all words");
        findButton.setToolTipText ("Find a word");
        addButton.setToolTipText ("Add a word");
        deleteButton.setToolTipText ("Delete a word");


        setPreferredSize (new Dimension (281, 460));
        setLayout (null);

        add (displayButton);
        add (findButton);
        add (addButton);
        add (displayWords);
        add (menuBar);
        add (wordInput);
        add (inputWord);
        add (mpLabel);
        add (deleteButton);

        displayButton.addActionListener(this);
            findButton.addActionListener(this);
            addButton.addActionListener(this);
            deleteButton.addActionListener(this);
            exitItem.addActionListener(this);
            setwordsItem.addActionListener(this);

            fileMenu.setMnemonic('F');
            exitItem.setMnemonic('X');
            configureMenu.setMnemonic('C');
            helpMenu.setMnemonic('H');
            loadItem.setMnemonic('L');


        displayButton.setBounds (10, 400, 145, 30);
        findButton.setBounds (175, 40, 95, 25);
        addButton.setBounds (10, 365, 70, 25);
        displayWords.setBounds (10, 75, 260, 280);
        menuBar.setBounds (0, 0, 705, 25);
        wordInput.setBounds (90, 365, 180, 25);
        inputWord.setBounds (10, 40, 155, 25);
        mpLabel.setBounds (5, 440, 135, 25);
        deleteButton.setBounds (165, 400, 110, 30);

        displayWords.setEditable(false);
    }

     public void actionPerformed (ActionEvent jnd)
     {
            if(jnd.getSource() == exitItem)
               {
                    System.exit(0);
               }
     }
On Thursday, October 23, 2008 5:57:46 PM UTC-7, justineee wrote:
> Hi again everyone,
> 
> I am quite new to java and this is what I have with my project..
> My problem is.. the compiler cannot find menu item "exitItem" in the
> actionPerformed method..
> 
> import java.awt.*;
> import java.awt.event.*;
> import javax.swing.*;
> import javax.swing.event.*;
> 
> public class MainFrame extends JPanel implements ActionListener {
>     private JButton displayButton;
>     private JButton findButton;
>     private JButton addButton;
>     private JTextArea displayWords;
>     private JMenuBar menuBar;
>     private JTextField wordInput;
>     private JTextField inputWord;
>     private JLabel mpLabel;
>     private JButton deleteButton;
> 
>     public MainFrame()
>     {
>         JMenu fileMenu = new JMenu ("File");
>         JMenuItem exitItem = new JMenuItem ("Exit");
>         JMenuItem loadItem = new JMenuItem ("Load");
>         JMenu configureMenu = new JMenu ("Configure");
>         JMenuItem setwordsItem = new JMenuItem ("Set number of
> words");
>         JMenu helpMenu = new JMenu ("Help");
>         JMenuItem contentsItem = new JMenuItem ("Contents");
>         JMenuItem aboutItem = new JMenuItem ("About");
> 
>         fileMenu.add (loadItem);
>         fileMenu.add (exitItem);
>         configureMenu.add (setwordsItem);
>         helpMenu.add (aboutItem);
>         helpMenu.add (contentsItem);
> 
>         displayButton = new JButton ("Display Words");
>         findButton = new JButton ("Find");
>         addButton = new JButton ("Add");
>         displayWords = new JTextArea (5, 5);
>         menuBar = new JMenuBar();
>         menuBar.add (fileMenu);
>         menuBar.add (configureMenu);
>         menuBar.add (helpMenu);
>         wordInput = new JTextField (6);
>         inputWord = new JTextField (5);
>         mpLabel = new JLabel ("E-Dictionary v1.0");
>         deleteButton = new JButton ("Delete");
> 
>         displayButton.setToolTipText ("Display all words");
>         findButton.setToolTipText ("Find a word");
>         addButton.setToolTipText ("Add a word");
>         deleteButton.setToolTipText ("Delete a word");
> 
> 
>         setPreferredSize (new Dimension (281, 460));
>         setLayout (null);
> 
>         add (displayButton);
>         add (findButton);
>         add (addButton);
>         add (displayWords);
>         add (menuBar);
>         add (wordInput);
>         add (inputWord);
>         add (mpLabel);
>         add (deleteButton);
> 
>         displayButton.addActionListener(this);
>     	findButton.addActionListener(this);
>     	addButton.addActionListener(this);
>     	deleteButton.addActionListener(this);
>     	exitItem.addActionListener(this);
>     	setwordsItem.addActionListener(this);
> 
>     	fileMenu.setMnemonic('F');
>     	exitItem.setMnemonic('X');
>     	configureMenu.setMnemonic('C');
>     	helpMenu.setMnemonic('H');
>     	loadItem.setMnemonic('L');
> 
> 
>         displayButton.setBounds (10, 400, 145, 30);
>         findButton.setBounds (175, 40, 95, 25);
>         addButton.setBounds (10, 365, 70, 25);
>         displayWords.setBounds (10, 75, 260, 280);
>         menuBar.setBounds (0, 0, 705, 25);
>         wordInput.setBounds (90, 365, 180, 25);
>         inputWord.setBounds (10, 40, 155, 25);
>         mpLabel.setBounds (5, 440, 135, 25);
>         deleteButton.setBounds (165, 400, 110, 30);
> 
>         displayWords.setEditable(false);
>     }
> 
>      public void actionPerformed (ActionEvent jnd)
>      {
>             if(jnd.getSource() == exitItem)
>                {
>                     System.exit(0);
>                }
>      }
> 
> }
> 
> 
> 
> Can anyone pls give me some tips?
> Thanks
> 
> Justine

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Re: "cannot find symbol" on menuItem for ActionListener suku260@gmail.com - 2013-12-30 07:53 -0800

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