• 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

    • Just WHY... I wonder if some executive really pushed for this to come up because of SOME REASON that bothered the dude... Or maybe so that it doesn't overlap with the OCD in some handheld, something like that?
    • OneDrive search is currently broken for many users by Taras Buria If you are trying to find a certain file in your OneDrive storage, but the service just won't give you the stuff you need, you are likely experiencing an issue that Microsoft has just confirmed. The company updated the official OneDrive documentation with a list of known bugs to clarify that the service currently exhibits problems with the search functionality. According to Microsoft, the bug affects four platforms: Windows, iOS, Android, and Web (macOS users are spared). The company says that affected users see black search results, and the storage does not return files that certainly exist (do not blame Microsoft if OneDrive cannot find the file you accidentally deleted or renamed). Fortunately, files are intact—it is just the search that cannot find them and present them to you. Another good thing is that the issue does not appear to affect 100% of users. Microsoft says only "a subset of users" experience the bug. Neowin checked a bunch of systems with personal and work OneDrive accounts, and all of them found the requested files without any issues. Unfortunately, if you are affected, there is nothing you can do at this point. Microsoft made it clear that there are no workarounds. Therefore, you will have to manually scavenge your OneDrive folders (they can now be colored!) to search for the needed file. Microsoft added that it understands how disruptive this bug could be, and it is "working with urgency" to resolve the bug as quickly as possible. You can check out the list of known OneDrive bugs and their possible workarounds in the official support document. In other news about OneDrive frustration, Microsoft recently locked out a user who was attempting to move a bunch of important data from old hard drives to OneDrive. Eighteen attempts to resolve the issue led to nothing but automated replies from Microsoft. You can read more about that wild story here.
    • If anyone thinks bringing manufacturing back will result in a bazillion jobs should heed this information. They will be plants full of robots with human supervisors. It’s the only way the products have a chance to be affordable.
    • You can’t sell BS unless you have autonomy as a sales gimmick. They don’t have the technology, I’ve been in several Tesla Swasticars, they are not safe and self driving barely works - their implementation is incredibly dangerous and still very error prone. They are selling this as a feature to assure safety, the reality is they know their technology isn’t safe and have humans there when it’s not fully able to do what you want it to. If they hired drivers and didn’t have any self driving they are then basically competing with uber and they don’t have the numbers of cars to compete so they sell fake self driving with humans and hope they fix their problems in the meantime. Felon skum has always been a snake oil salesman and people fall for it.
    • Exactly, this defeats the point entirely.
  • Recent Achievements

    • Week One Done
      BlakeBringer earned a badge
      Week One Done
    • Week One Done
      Helen Shafer earned a badge
      Week One Done
    • First Post
      emptyother earned a badge
      First Post
    • Week One Done
      Crunchy6 earned a badge
      Week One Done
    • One Month Later
      KynanSEIT earned a badge
      One Month Later
  • Popular Contributors

    1. 1
      +primortal
      669
    2. 2
      ATLien_0
      271
    3. 3
      Michael Scrip
      229
    4. 4
      Steven P.
      166
    5. 5
      +FloatingFatMan
      161
  • Tell a friend

    Love Neowin? Tell a friend!