There is a problem with maximised MDI children

Description

Newsgroups: comp.lang.pascal.delphi.misc
Subject: Problem with maximised MDI children
From: Catherine@polyhdrn.demon.co.uk (Catherine Rees-Lay)
Date: Wed, 07 Feb 96 13:05:20 GMT

Has anyone else seen this problem, or got any ideas on a workaround? I've tried everything I can think of...

The symptom is that if you open an MDI child, minimise it, maximise it, then open another one, the second one comes up maximised and the first one is restored to its minimised state. So far so good. However, the system menu on the first one is now disabled. Click on the icon and bang, the system locks up (Win 3.1 or Win 95). The BorderIcons property still contains all 3 possibilities, and if you maximise the window then minimise it again the system menu icon reappears (under Win 95) - so it knows it's supposed to have one!

Unfortunately, I can't reproduce the problem with a test case - but I can reproduce the disastrous (system-hang) side effects - just create a project with the MDI template, remove biSystemMenu from the MDI children's bordericons, run the project, open a child window and click Minimise All. Now click on the child window's icon. Crunch.

Does anyone have any ideas as to how to get round either the symptom or the side-effect? Deleting then adding biSystemMenu to the bordericons works, but it won't let me put this in a WM_SIZE message as I get an error saying I can't change Visible in OnShow or OnHide (I thought I could at least avoid the system-lock this way) and I can't think of another suitable catch-all place.

My next trick will be to build another MDI frame and add all my code back to it routine by routine in the hope that it will go away, since it doesn't happen with a trivial MDI application, but given the current size of my project I'm not looking forward to it :-(

I have Delphi 1.02 and the VCL source code, and it's not happening anywhere I can single-step to.

Borland has accidentally left out the ISAPI and NSAPI DLL support from the Delphi 3.0 Professional distribution CD-ROM.

Description

Solution / workaround

The Client/Server edition is not affected. The missing files have been put on Borland's WWW server for download. The address is:
http://www.borland.com/devsupport/delphi/whatsnew.html
"Place in the \Source\RTL\Win directory"

There is a problem with TQuery and sorting by time

Description

Newsgroups: comp.lang.pascal.delphi.databases
Subject: Re: Delphi SQL broken?????? DOES NOT WORK!!!!!!
From: gregc@cryptocard.com (Greg Carter)
Date: 15 Feb 1996 16:23:13 GMT

I have a database table that I am successfully accessing using the TQuery component and i need to sort the records in various ways. One way I need to sort it is by date and time. I have a BDE created database with the field names Date and Time and the following code snippet generates errors at runtime....

Dates work, Times DON'T. Who knows why, but I have tried and tried, even spent an hour on the phone with a Borland tech guy, who confirmed they don't. I ended up using a TTable and applying a RANGE, which seems to work, but TQUERY just does't like compares on times field.

There is a problem with the DBLookupCombo

Description

Newsgroups: comp.lang.pascal.delphi.misc
Subject: Re: DBLookupCombo problem
From: koterski@borland.com (Steve Koterski)
Date: Fri, 09 Feb 1996 02:31:27 GMT

On 8 Feb 1996 14:43:11 GMT, drewsxer@superlink.net (Eric Drews) wrote:

I had the form wizard create a form for an application. After some modiciations, in which I added a DBLookupCombo to the form, I was (relatively) satisfied with the form performance. After further review, I decided to change the FormStyle property to fsStayOnTop. The form now stays on top of the application main form. All's cool! Now the problem.

For the DBLookupCombo, the drop-down part of it drops down BEHIND the form when the little arrow is clicked. I received a suggestion from a fellow Delphi-ite regarding Z-Order which I duly investigated and found that changes there did not solve the problem. If the FormStyle is changed back to fsNormal again, the DBLookupCombo works okay. There is also a DBComboBox on the form as well, it works just fine.

The problem you are encountering is known, and it has nothing to do with the Database Form Expert. It has to do with the nature of the TDBLookupCombo component.

This component is not a true Windows combobox. Basically, the list for this component is a derivative of a window. Thus, when the form has a FormStyle setting of fsStayOnTop, the form's window stays on top of the TDBLookupCombo list window.

There is currently no workaround for this, aside from not combining a TDBLookupCombo component with a stay-on-top window. It can be recreated by adding a TTable, a TDataSource, and a TDBLookupCombo to a blank form, resizing the form to force the list to exceed the form's boundary, and setting that form's FormStyle property to fsStayOnTop. The equivalent component in Delphi 2.0 does not exhibit this incorrect behavior.

There can be floating point problems in a DLL

Description

Floating point operations inside a DLL may cause problems.

The problem is that the TextToFloat procedure (found in FFMT.ASM, if you have the VCL Source) tries to access a global variable with the app's DSeg loaded rather than the DLL's DSeg.

Solution / workaround

By Steve Teixeira
If you have the source, you can work-around this problem by inserting a POP DS instruction immediately prior to the call to Power10 in the TextToFloat proc. You must also remove the POP DS instruction found immediately prior to the @@8: label in TextToFloat. I'm afraid there is currently no work-around if you don't have the VCL source.