Puedo colocar un método en el campo lpfnWndProc del registro WndClassEX Es decir algo parecido a esto :

VAR
  ClaseVentana : WndClassEX;
   ...
   ClaseVentana.lpfnWndProc := WndProc(Método);

***************************** TRANSALATE *******************************

may I allocate a metthod in the field lpfnWndProc of the WndClassEX Registers?
Like this :

VAR
  ClaseVentana : WndClassEX;
   ...
   ClaseVentana.lpfnWndProc := WndProc(Método);

No, you cannot assign methods to normal procedure variables, only normal procedures. The reason is that methods always expect an extra parameter containing the self pointer of the object/class instance they are working on. If you do the above, then when windows calls you "wndproc" (which isn't really a wndproc, since you have to add an explicit type cast for the compiler to accept the statement), it won't pass any self pointer and as such the method will not work correctly.

Jonas

Message: 4
Date: Fri, 12 Oct 2001 15:53:25 +0200
Subject: Re: [fpc-pascal]Method in WndClassEX
From: Jonas Maebe
To:
Reply-To:

No, you cannot assign methods to normal procedure variables, only normal procedures. The reason is that methods always expect an extra parameter containing the self pointer of the object/class instance they are working on. If you do the above, then when windows calls you "wndproc" (which isn't really a wndproc, since you have to add an explicit type cast for the compiler to accept the statement), it won't pass any self pointer and as such the method will not work correctly.

Jonas

Existe alguna manera de pasar un metodo al registro lpfnWndProc usando ensamblador o algo mejor?

Do you know when allocate a metthod in the field lpfnWndProc of the WndClassEX using Assembler or something best?

As I said: no, there is no way to use a method instead of a normal procedure as a call-back if the call-back is supposed to be a normal procedure. No matter how much assembler you use, Windows will never pass a self pointer to your method.

Jonas

----- Original Message -----