Active X "Catastrophic Failure"...

[Roberto Sarti]

We wrote a simple ActiveX control using Visual C++ 5.0 with service
pack 2 of Visual Studio.

The control was created by MFC Active X control wizard, setting the
"invisible at run time" and "windowless activation" checks.

The control code is very simple: it has only a property (short MyValue),
three methods
(void increment(), void decrement() and short obtainvalue()) and one
event fired when MyValue becomes 10.

It works correctly in VC++, VBasic and Excel!

Under Delphi 3.0, calling any of the methods raises an exception class
EOleSysError with message "Catastrophic failure" and the process
stops.

This doesn't happen if the control is generated "Visible at run time".

How can we write ActiveX controls, possibly with Delphi 3, that are not
visible at run time and that are dynamically instantiable (like UDP
control in Delphi component palette) ?

Thanks.

[Butcher]

Add a property in the control. Then set it before you call any methods.
This will allow the control to work. I don't know why, but it does.

If anyone knows why, I'd like to know.
--
Thanks,
Butch Raines

bu...@videogate.com

Roberto Sarti <rarti_...@mail.asianet.it> wrote in article
<3469CE...@mail.asianet.it>...

[Roberto Sarti]

After the upgrade to Delphi 3.01 the control works correctly.

!:-)

We 're now trying to do the same using only Delphi...

There's still some problem with the visibility at design time...

I'll start a new news thread if the problem persists.

Thanks to all.