• 0

JAVA GUI error message


Question

package Lab4;

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


public class GUI_Element implements ActionListener{
    // Create a frame window

    public static final int WIDTH = 500;
    public static final int HEIGHT = 400;
    public static final int NUMBER_OF_DIGITS = 30;

    private JTextField ioField;
    private double result = 0.0;

    public GUI_Element () {
        JFrame frame = new JFrame ("Mortgage Calculator");
        frame.setSize (WIDTH, HEIGHT);
        frame.setLayout(new GridLayout(7,1,10,10));
}

Okay so I have this java program written. i'm trying to build a GUI for the first time, so just a beginner at this and I'm using Netbeans.

I get this error on the class name GUI_Element

GUI_Element is not abstract and does not override abstract method actionPerformed in java.awt.event.ActionListener

I have no idea why I'm getting this error.

Please help

Link to comment
https://www.neowin.net/forum/topic/886128-java-gui-error-message/
Share on other sites

10 answers to this question

Recommended Posts

  • 0

I dont mess with gui at all but it could be that you need super() in your constructor as the class is implementing the awt.

^ thats not it.

you could just make the class abstract and implement everything that is needed in your constructor.

public abstract class GUI_Element implements ActionListener{

  • 0

Your class GUI_Element implements an interface (ActionListener). ActionListener requires that implementing classes override the method actionPerformed. You need to define a method called actionPerformed.

It must match the signature in http://java.sun.com/javase/6/docs/api/java/awt/event/ActionListener.html .

so something like:

public void actionPerfomed(ActionEvent e){
   if(e.getSource()==jButton1){
      //do work
   }
}

  • 0

Okay so after adding more code to my file, this is what I ended up with. It looks right to me but the only thing that I need is to make the text field, button smaller so that I can fit the outputs on the same window. I have in all 7 outputs. In the picture I've only shown 2 for now.

Is there a way to make the textfield and button smaller?

Thanks.

post-234729-12694907304266.jpg

  • 0

A GridLayout will make every Component in the Grid the same size no matter what. GridBagLayout will let you set relative sizes, but it's somewhat difficult to figure out. The best bet if you don't want to code the GUI by hand is to use NetBeans IDE. It has a drag-and-drop GUI creator.

Otherwise, you'll want to read this: http://java.sun.com/docs/books/tutorial/uiswing/layout/visual.html

  • 0

^ Thanks for the link. I tried using BorderLayout in mine.

Seems okay to me till now.

Now where I'm stuck is, I want the text "Status of the Program: Waiting for user to enter all the values" to fit on the window. However, my GUI cuts it off. I have no idea how to make it not cut the text I've written.

Any help please?

Thanks :)

post-234729-12695709436469.jpg

  • 0

I don't quite understand how we use HTML tags. Can you give me a link that will make things more clearer?

I'm building on Netbeans. I have an assignment and its due tomorrow :(. I can't use the Netbeans GUI builder. I have to write all the code myself.

Thanks for the help :)

EDIT:

nvm I found this link:

http://java.sun.com/docs/books/tutorial/uiswing/components/html.html

Thanks for the kind help dontocsata!

EDIT2:

okay still stuck. So I have this:

        status.setText(" <html><b>Status of the Program: Waiting for user </b> <b>to enter all the values</b>");

where status is a JLabel.

HTML doesn't seem to work in this.

I don't really know if I'm right though.

This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Posts

    • WYSIWYG Web Builder 20.2.1 by Razvan Serea Web Buialder is a WYSIWYG (What-You-See-Is-What-You-Get) program used to create complete web sites. WYSIWYG means that the finished page will display exactly the way it was designed. The program generates HTML (HyperText Markup Language) tags while you point and click on desired functions; you can create a web page without learning HTML. Just drag and drop objects to the page position them "anywhere" you want and when youre finished publish it to your web server (using the build in Publish tool). Web Builder gives you full control over the content and layout of your web pages. One Web Builder project file can hold multiple web pages. Desktop publishing for the web, build web sites as easy as Drag & Drop "One Click Publishing" No FTP program needed. No special hosting required, use with any Hosting Service! Easily create forms using the built-in Form Wizard plus Form validation tools and built-in CAPTCHA. Advanced graphics tools like shapes, textart, rotation, shadows and many other image effects. Fully integrated jQuery UI (Accordion, Tabs etc), animations, effects and built-in ThemeRoller theme editor. Google compatible sitemap generator / PayPal eCommerce Tools Many navigation tools available: Navigation bars, tab menus, dropdown menus, sitetree, slidemenus. Built-in Slide Shows, Photo Galleries, Rollover images, Banners etc. Support for YouTube, Flash Video, Windows Media Player and many other video formats. Unique extension (add-on) system with already more than 250 extensions available! Create HTML5 / CSS3 websites today HTML5 document type (optimized HTML5 output). HTML5 audio/video and YouTube HTML5 support. HTML5 forms: native form validation, new input types and options, web storage. HTML5 canvas and svg support in shapes and other drawing tools. CSS3 @font-face. Use non web safe fonts in all modern browsers. CSS3 opacity, border radius, box shadow. CSS3 gradients. Add cool gradient effects using native CSS3 (no images). CSS3 navigation menu. Create awesome menus without using JavaScript or images. CSS3 animations and transitions. Including support for 2D and 3D transforms! Features for advanced users: Login Tools/Page Password Protection. Built-in Content Management System with many plug-ins (guestbook, faq, downloads, photo album etc). Add custom HTML code with the HTML tools. JavaScript Events: Show/hide objects (with animation), timers, move objects, change styles etc. Layers: Sticky layer, Docking layer, Floating layer, Modal layer, Anchored layer, Strechable layer and more! jQuery Theme Manager, create your own themes for the built-in jQuery UI widgets. Style Manager (global styling, H1, H2, H3 etc). Master Frames and Master Objects: reuse common element in your website. and much more! WYSIWYG Web Builder 20.2.1 changelog: Improved: Images in the properties of Photo Gallery, Photo Grid, Photo Collage and Slide Show can now be re-arrange using drag & drop. Improved: Default aspect ratio of HTML5 audio Fixed: Issue with list item icon offset in workspace. Fixed: 'Edit' button text in Login Admin cannot be changed. Fixed: Issue with Card max-width size calculation in breakpoints Fixed: Issue with (fixed) Layout Grid column height in breakpoints. Download: WYSIWYG Web Builder 64-bit | 30.1 MB (Shareware) Download: WYSIWYG Web Builder 32-bit | 28.0 MB Screenshot: >> Click here << Link: Home Page | Templates | Free extras/addons | Changelog Get alerted to all of our Software updates on Twitter at @NeowinSoftware
    • Damn no doubt this is gonna be good, can't think of many franchises as consistent as RE (apart from 3 remake)
    • There are two version of qbittorrent 5.1.0 The normal version which I think is based of QT5 & the QT6 lt20 version. I'm currently using the QT6 LT20 version of 5.1.0 and it downloaded an ubuntu iso perfectly fine.
    • Are we forgetting the hardware degradation on 13th and 14th gen??
    • Cry more. The Ukrainians who had internet access because of Starlink were trash too, huh?
  • Recent Achievements

    • One Year In
      Vladimir Migunov earned a badge
      One Year In
    • One Month Later
      daelos earned a badge
      One Month Later
    • Week One Done
      daelos earned a badge
      Week One Done
    • Mentor
      Karlston went up a rank
      Mentor
    • One Month Later
      EdwardFranciscoVilla earned a badge
      One Month Later
  • Popular Contributors

    1. 1
      +primortal
      494
    2. 2
      snowy owl
      252
    3. 3
      +FloatingFatMan
      250
    4. 4
      ATLien_0
      225
    5. 5
      +Edouard
      181
  • Tell a friend

    Love Neowin? Tell a friend!