Want a toolbar status window for a modal application...

Posted on 2001-06-08
Last Modified: 2010-04-06
I need my application to have a "Machine status" tool window so the machine can be controlled using the tool window.

The problem is that this part of the application uses modal windows and I need the tool window to be accessable from any of the windows.

"TestForm" modal window
     \ test type 1 modal window
     \ test type 2 modal window

What I've found so far is that if I create the form and have it owned by TestForm, the "child" modal forms don't allow you to press buttons on the tool window.  What I did so far is that when I display a new "test type" form, I recreate the tool window and make it owned by the "test type".

I think I'm going about this the wrong way.  Here's what I've tried:

FormCreate:  Not really suitable for various reasons but if I use it anyhow, I can't access the window (it's as though it's owned by another form).

FormShow:  If it's put here, I get some pretty ugly flickering when the form loads.  LockWindowUpdate didn't help.

FormResize:  Definitely not a good idea to put it here; sometimes get access violations even though I'm always checking to ensure the form is there first.  Always setting to nil immediatly upon Free.

How can I share this window without recreating it all the time?  Hopefully someone has an idea which will fit my situation.

Question by:mikepj
  • 4
  • 2

Expert Comment

ID: 6169386
Can't you try to do it the other way?
Let your "tool window" create the "machine window"?

Or don't make your tool window a modal window.

Author Comment

ID: 6169431
Thank you for your reply.

The tool window won't necessarily exist.

If I were to be able to change the order, I would think I would have the same problem because the tool window would instead own the modal test window.

I think I've solved the problem by:

1) using the FormResize event as a time to recreate the window
2) put up a semaphore so that it's impossible for any use of the window to be attempted between FREE and :=nil (there's nothing inbetween them but when I did that, it seems to work fine.)

Thanks again for your comments!  Just now I think I'll leave it alone--it works!
LVL 22

Accepted Solution

mnasman earned 200 total points
ID: 6170406

  Try to do that in FormActivate event.
  could u send me a copy of ur program and what do u want to do at
What Security Threats Are You Missing?

Enhance your security with threat intelligence from the web. Get trending threat insights on hackers, exploits, and suspicious IP addresses delivered to your inbox with our free Cyber Daily.


Expert Comment

ID: 6170889
So the answer is:

use the FormResize event as a time to recreate the window
and put up a semaphore so that it's impossible for any use of the window to be
attempted between FREE and :=nil (there's nothing inbetween them but when I did that,
it seems to work fine.

Author Comment

ID: 6171399
Hi Moorrees,

I guess you don't know how Experts Exchange works.  You've "recycled" my answer; if I were to accept the answer, two things happen:

- nobody will provide a better answer
- I give the points away rather than keeping the points when I had I had provided my own answer.


Author Comment

ID: 6171412
Thank you for your answer.  

I totally forgot about FormActivate.  It works great now--thanks!

I also did the following so frmToBeDestroyed would be made unavailable before destruction started.


I knew there must have been a better answer!


Author Comment

ID: 6181990
Found out some more through experience; I figured I'd relate my experiences in case anyone else finds them to be useful.

If form A is the parent of form B I will have problems if I don't destroy form B before closing form A.
I've changed it now so upon activate of form A, form B will be created.  Upon close of  form A, form B will be destroyed.

Featured Post

Maximize Your Threat Intelligence Reporting

Reporting is one of the most important and least talked about aspects of a world-class threat intelligence program. Here’s how to do it right.

Join & Write a Comment

This article explains how to create forms/units independent of other forms/units object names in a delphi project. Have you ever created a form for user input in a Delphi project and then had the need to have that same form in a other Delphi proj…
Introduction I have seen many questions in this Delphi topic area where queries in threads are needed or suggested. I know bumped into a similar need. This article will address some of the concepts when dealing with a multithreaded delphi database…
This video discusses moving either the default database or any database to a new volume.
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

757 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

19 Experts available now in Live!

Get 1:1 Help Now