actionlistener/itemStateChange help?

[retrosleeper]

Im sorry if this sounds really silly but I could do with some help with a bit of code.
I have setup a jcombobox in my GUI from an array of months i.e jan, feb etc.
What I am trying to do is write an actionlistener/itemStateChange to getselectedindex of the combobox and then at the moment just System.out.println(i)
But I am really struggling as I cannot seem to get it to work. Hope you can help
thank you :)

[Norm]

Post the code you need help with. Be sure to put it in code tags.

[retrosleeper]

public class RainfallGUI extends JFrame implements ActionListener, ItemListener {
	JPanel mainPanel = new JPanel();
	JPanel topPanel = new JPanel();
	JLabel testinfo = new JLabel("Rain",JLabel.CENTER);
	
	String[] YearString = { "1974", "1975", "1976", "1977", "1978", "1979","1980","1981","1982","1983","1984","1985","1986","1987","1988","1989","1990","1991","1992","1993","1994","1995","1996","1997","1998","1999","2000","2001","2002","2003","2004","2005","2006","2007","2008","2009","2010","2011","2012" };
	String[] MonthString = {"January","February","March","April","May","June","July","August","September","October","November","December"};
	String[] DayString = { "1St", "2nd", "3rd", "4th", "5th","6th","7th","8th","9th","10th","11th","12th","13th","14th","15th","16th","17th","18th","19th","20th","21st","22nd","23rd","24th","25th","26th","27th","28th","29th","30th","31st"};
	JComboBox DayList1 = new JComboBox(DayString);
	JComboBox MonthList1 = new JComboBox(MonthString);
	JComboBox YearList1 = new JComboBox(YearString);
	int getdaynumber =0;
	int getmonthnumber =0;
	int getyearnumber =0;
	
	public RainfallGUI() {
		super("rain fall data");
		this.setSize(800,800);
		this.setResizable(false);
		this.setLayout(new BorderLayout());
		this.add("Center", mainPanel);
		
		this.add("North", topPanel);
		topPanel.setLayout(new GridLayout());
		topPanel.add(DayList1);
		topPanel.add(MonthList1);
		topPanel.add(YearList1);
	
	this.setVisible(true);
	this.setDefaultCloseOperation(EXIT_ON_CLOSE);
	
}
	public void actionPerformed(ActionEvent e) {
		        JComboBox getmonthnumber = (JComboBox)e.getSource();
		    	getmonthnumber = MonthList1.getSelectedIndex();
		    	System.out.println(getmonthnumber);
		    }
		}

im trying to get the getmonthnumber variable to change when i change the selection on the MonthList1 combobox and print to the system so know it has changed

[Norm]

I see two variables with that name. Which one are you having problems with?
Does that code compile?

[retrosleeper]

im having a problem with the whole actionperformed part.
it runs and shows no errors in eclipse but does not print anything to system when i change the combo box im rather new to java, i am sorry if its something really silly i have done and am thankful for any help

[Norm]

Why are there two variables with the same name?

it runs and shows no errors in eclipse

The posted code does not compile without errors. Without a clean compile I can not execute it.
Fix the compiler errors and try it again.

Also read up on listeners:
http://docs.oracle.com/javase/tutori...nts/index.html

[retrosleeper]

http://www.java-forums.org/newreply....3171&noquote=1

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

public class RainfallGUI extends JFrame implements ActionListener, ItemListener {
    JPanel mainPanel = new JPanel();
    JPanel topPanel = new JPanel();  
    String[] YearString = { "1974", "1975", "1976", "1977", "1978", "1979","1980","1981","1982","1983","1984" };
    String[] MonthString = {"January","February","March","April","May","June","July","August","September"};
    String[] DayString = { "1St", "2nd", "3rd", "4th", "5th","6th","7th","8th","9th","10th","11th","12th"};
    JComboBox DayList1 = new JComboBox(DayString);
    JComboBox MonthList1 = new JComboBox(MonthString);
    JComboBox YearList1 = new JComboBox(YearString);
    int getdaynumber =0;
    int getmonthnumber =0;
    int getyearnumber =0;
     
    public RainfallGUI() {
        super("rain fall data");
        this.setSize(800,800);
        this.setResizable(false);
        this.setLayout(new BorderLayout());
        this.add("Center", mainPanel);
         
        this.add("North", topPanel);
        topPanel.setLayout(new GridLayout());
        topPanel.add(DayList1);
        topPanel.add(MonthList1);
        topPanel.add(YearList1);
     
    this.setVisible(true);
    this.setDefaultCloseOperation(EXIT_ON_CLOSE);
     
}
    public void actionPerformed(ActionEvent e) {
    	MonthList1 = (JComboBox) e.getSource();
                getmonthnumber = MonthList1.getSelectedIndex();
                System.out.println(getmonthnumber);
            }
	@Override
	public void itemStateChanged(ItemEvent e) {
		// TODO Auto-generated method stub
		
	}
        }

I have removed/corrected some things and made the arrays smaller so they fit on the page this should now compile
cheers

[Norm]

What happens when you execute it?

Have you looked at the tutorial on how to write listeners?
Lesson: Writing Event Listeners (The Java™ Tutorials > Creating a GUI With JFC/Swing)

[DarrylBurke]

Code Conventions for the Java Programming Language: Contents

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