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Re: I need a different approach - suggestions please

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From Lew <lewbloch@gmail.com>
Newsgroups comp.lang.java.programmer
Subject Re: I need a different approach - suggestions please
Date Wed, 27 Jun 2012 18:54:21 -0700 (PDT)
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bilsch wrote:
> Lew wrote:
>> There are a few mistakes in your code.
>>
>> You don't need to call 'super()' in the constructor explicitly.
>> That's what happens by default anyway.
>>
>> You called the constructor directly from the 'main()' routine. That means
>> you called it from the primary thread of the program. You don't know this
>> yet, probably, unless you've already studied concurrency in Java a little bit.
>>
>> The problem is that the GUI won't work right if you do that. You have to
>> move GUI actions onto the "Event Dispatch Thread" (EDT), a background
>> thread that the system creates to handle all GUI actions.
>>
>> Also, you start all the action from the constructor. That's bad. As its name
>> implies, a constructor's purpose is to _construct_ an object, not run its logic.
>> Run the logic after construction completes and the instance is no longer in a
>> partially-built state.
>>
>> And make your indentation consistent with the Java coding conventions (available
>> on line).
>>
>> So all together, you'd do something like:
>>
>>   public static void main(String[] arguments) {
>>      java.awt.EventQueue.invokeAndWait( new Runnable() {
>>          @Override public void run() {
>>               CalcGUIQ1 calculator = new CalcGUIQ1();
>>               calculator.setVisible(true);
>>           }
>>       });
>>   }
> 
> With help I've gotten some errors out of the program but I have reached 
> a point where something just won't work how it should.  Your comments 

What doesn't work, and how should it?

> here lead me to believe the reason is the basic way I have things laid 
> out.  But I don't know how to:
> 
>  > move GUI actions onto the "Event Dispatch Thread" (EDT), further I 
> dont know how to write an EDT, or what specifically are 'GUI actions' as 
> opposed to other lines that relate to the GUI.

You don't write the EDT. Did you read the tutorial link I provided?

<http://docs.oracle.com/javase/tutorial/uiswing/concurrency/index.html>

GUI actions are all things that happen on the GUI, such as creating 
a 'JFrame', calling 'pack()', playing with 'Graphics', or anything else that 
is part of the GUI. Non-GUI actions are things like writing files, calculating 
values, updating the logical model, or anything else that is not part of 
the GUI.

Do please read the tutorial to which I linked. There's a reason I provided 
that link.


> Also, I thought the stuff I have in the constructor belonged there.

Not all of it. The program itself must run from a *completely* 
constructed object. You start the program from inside the 
constructor, therefore it is running on an *incompletely* 
constructed object.

> I dont know where to call the constructor from if not from 'main'.

You should call the constructor from 'main()', provided you properly 
guard it inside the 'invokeAndWait()' call.

Why did you think I recommended otherwise?
 
> I did some reading about threads being unsafe.
> 
> It would be very helpful to me if you could show how to rearrange the 
> code like you say would be better.  If you have the time, it would be 
> very helpful.  Thanks.

What was wrong with what I already showed you (and you quoted)?

-- 
Lew

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Thread

I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-25 15:31 -0700
  Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-25 16:15 -0700
    Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-25 16:47 -0700
      Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-25 18:10 -0700
        Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-26 13:04 -0700
          Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-26 14:01 -0700
          Re: I need a different approach - suggestions please Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-26 17:21 -0400
            Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-27 14:44 -0700
              Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-27 14:56 -0700
              Re: I need a different approach - suggestions please Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-27 18:13 -0400
                Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-27 18:48 -0700
              Re: I need a different approach - suggestions please Patricia Shanahan <pats@acm.org> - 2012-06-27 15:21 -0700
                Re: I need a different approach - suggestions please Jail Bush Cronies <do.not@ask.me> - 2012-06-27 18:46 -0400
          Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-26 14:25 -0700
            Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 14:32 -0700
              Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-26 17:49 -0400
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 15:20 -0700
                Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-27 17:30 -0700
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-27 18:09 -0700
        Re: I need a different approach - suggestions please Wanja Gayk <brixomatic@yahoo.com> - 2012-07-02 11:21 +0200
      Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-25 18:36 -0700
        Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-26 13:24 -0700
          Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 13:49 -0700
          Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-26 14:04 -0700
            Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 14:34 -0700
              Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-26 16:26 -0700
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 16:47 -0700
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-26 20:04 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-26 22:18 -0400
                Re: I need a different approach - suggestions please Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-06-26 22:59 -0400
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-27 21:30 -0400
                Re: I need a different approach - suggestions please Wanja Gayk <brixomatic@yahoo.com> - 2012-07-02 11:32 +0200
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-07-02 09:47 -0700
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-26 20:06 -0700
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-27 11:42 -0700
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 14:09 -0700
                Re: I need a different approach - suggestions please Patricia Shanahan <pats@acm.org> - 2012-06-27 15:11 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-27 21:59 -0400
                Re: I need a different approach - suggestions please Devil's Advocate <legal@hell.org> - 2012-06-27 22:17 -0400
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-27 21:40 -0400
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 19:12 -0700
                Re: I need a different approach - suggestions please Leif Roar Moldskred <leifm@dimnakorr.com> - 2012-06-27 20:47 -0500
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 19:12 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-27 21:28 -0400
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 19:14 -0700
                Re: I need a different approach - suggestions please Hydrangea <hydrangea393@foo.mail.quuzzle.edu> - 2012-06-27 22:28 -0400
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 21:05 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-27 22:32 -0400
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-27 21:08 -0700
          Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-26 14:10 -0700
            Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 14:35 -0700
              Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-26 17:51 -0400
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 15:20 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-26 19:35 -0400
                Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-26 16:44 -0700
                Re: I need a different approach - suggestions please Arne Vajhøj <arne@vajhoej.dk> - 2012-06-26 22:06 -0400
          Re: I need a different approach - suggestions please Patricia Shanahan <pats@acm.org> - 2012-06-27 08:15 -0700
        Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-27 18:36 -0700
          Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-27 18:54 -0700
            Re: I need a different approach - suggestions please B1ll G4tes <wm.gat3s@micro5oft.quux> - 2012-06-27 22:23 -0400
              Re: I need a different approach - suggestions please Lew <lewbloch@gmail.com> - 2012-06-28 09:55 -0700
            Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-28 04:02 -0700
              Re: I need a different approach - suggestions please Mike Winter <mlwinter@gmail.com> - 2012-06-28 04:55 -0700
                Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-28 07:33 -0700
                [OT] Message IDs (Re: I need a different approach - suggestions please) Mike Winter <mlwinter@gmail.com> - 2012-06-28 08:45 -0700
                Re: [OT] Message IDs (Re: I need a different approach - suggestions please) markspace <-@.> - 2012-06-28 09:39 -0700
                Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-28 09:44 -0700
                Re: I need a different approach - suggestions please Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-06-28 12:51 -0400
                Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-28 09:58 -0700
              Re: I need a different approach - suggestions please markspace <-@.> - 2012-06-28 07:32 -0700
  Re: I need a different approach - suggestions please Roedy Green <see_website@mindprod.com.invalid> - 2012-06-26 03:49 -0700
    Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-26 13:59 -0700
  Re: I need a different approach - suggestions please Patricia Shanahan <pats@acm.org> - 2012-06-29 08:12 -0700
    Re: I need a different approach - suggestions please Gene Wirchenko <genew@ocis.net> - 2012-06-29 10:02 -0700
    Re: I need a different approach - suggestions please bilsch <bilsch01@gmail.com> - 2012-06-29 13:07 -0700

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