ActiveX Component Expert

Posted on 1998-05-05
Last Modified: 2010-04-06
When I try to convert my component to an ActiveX control using the ActiveX expert (New ... ActiveX ... ActiveXControl), my component is not visible in the dropdownlist of VCL components. It is correctly installed and working as normal VCL component though, any ideas?
Question by:arnoldu
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Expert Comment

ID: 1341377
What does your component inherit from?


Author Comment

ID: 1341378
The component is inherited from TComponent - is there a problem with invisible components?

Accepted Solution

JimBob091197 earned 200 total points
ID: 1341379
Yip.  You can't have anything inherited directly from TComponent.  It must be a control (inherited from TCustomControl, or maybe TControl).

You could try changing it from "TMyWhatsIt = class(TComponent)" to TMyWhatsIt = class(TCustomControl)" and then in the constructor setting the Width & Height to 24, and keeping the Visible property False.  A bit of a work-around, but it should work.


Expert Comment

ID: 1341380
According to Delphi's help, a TActiveXControl must be derived from a TWinControl.

"TActiveXControl defines the core behavior and interfaces required of an ActiveX control and connects that behavior to any VCL control derived from TWinControl."


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