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javaswingjframedispose

When I dispose and reopen a JFrame, it doesn't show anything

I have a fairly simple Java Application I created with JFrames. There is more than one JFrame in my program. I have a menu launching at the beginning of the program. After going through the menu, I have the menu JFrame disposed.

The main JFrame has a menu button that should launch the exact same menu at a later time. However, when you launch the menu from inside of the ActionListener (when you press the menu button), the JFrame doesn't launch properly. None of the components show up and colors are off.

However, when the menu is launched from outside of the ActionListener, the JFrame shows up perfectly. I have tried multiple methods to fix this, but none of them have worked.

My full program code is available by clicking here.

  • The main class is "LetsMultiply5.java". This class also sets up the ActionListener.
  • The JFrame causing the problem is "MenuWindow.java".
  • "LetsMultiply5.java" calls the "Booter.java" class, which then calls the "MenuWindow.java".
  • "MainWindow.java" is the JFrame that has the "Menu" button.
  • For proof, "SpeedModer.java" calls the menu window after it has been disposed, and works.

================================EDIT================================

Also, I'd like to let you know that I realize my code is a little bit messy. I am not sure how else to write the code for this program.

I am forced to use Thread.sleep(x); because the Swing timers aren't what I am looking for. The Swing timers activate an ActionListener when the timer goes off. I need a system that will wait a second before continuing on with the code.

I realize that the while (repeater==0) loop with ActionListeners inside of it seems crazy, but that was the only way I could get it to work. If I put a single ActionListener and just had the while loop do no code inside of it, nothing happens when I press the button.

I would, as MadProgrammer mentioned:

Advice: Scrap your current approach and start again.

However, the way that I have my program currently coded is the only way that I know how to get what I need to do done. I read the tutorials, but still don't know how to improve the code in the way that you told me.

I thank everyone for trying to tell me to improve my bad "Java grammar", but as far as I am concerned, I am not going to continue this program for the next 20 years and make my millions off of it.

I have looked at the Swing timers before and I understand the whole new Timer(speed, this); concept, but I don't understand how this would make my code any better.

If anyone would like to show me how to fix my ActionListeners or Thread.sleep(x); lines, please tell me. Thank you.

Solution

  • You're blocking the Event Dispatching Thread with Thread.sleep(3000); - Don't do this, it will prevent the UI from been painted

    See Concurrency in Swing for more details about the problem and How to use Swing Timers for a possible solution

    You may also want to consider having a look at The Use of Multiple JFrames, Good/Bad Practice? and consider using CardLayout or JTabbedPane

    If you need to block the user temporarily (to display a error message or gather important details), consider using a modal JDialog. See How to Make Dialogs for more details