[fpc-pascal] Moving callbackfunctions to class

Michael Van Canneyt michael at freepascal.org
Thu Dec 30 18:01:38 CET 2010

On Thu, 30 Dec 2010, Darius Blaszyk wrote:

> Hi,
> GLut defines callback functions, one of them is the display function, which is defined as:
> TGlutVoidCallback = procedure; cdecl;
> This is set by calling glutDisplayFunc(@MyDisplayFunc); 
> As these functions are needed per window, I would like to encapsulate each window in a class something like:
> TMyGLutWindow = class
>   private
>     procedure MyDisplayFunc; cdecl;
>   public
>     constructor Create;
> end;
> In the constructor I would like to set the displayfunction. But doing this I get the error:
> Error: Incompatible types: got "<procedure variable type of procedure of object;CDecl>" expected "<procedure variable type of
> procedure;CDecl>"
> Though I understand the error, I do not know if there is a way to circumvent this?

No, there isn't.


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