A property missing (MouseMove)

[Peiman]

Hi.

I have a same definition of custom graphics for two projects. While one is compiled easily the other raises the "unknown identifier" error.

both of them are nearly like below

type
  TStyleCanvas = class(TCustomControl)
  public
    SRC : HDC;
    procedure EraseBackground(DC: HDC); override;
    procedure Paint; override;
  end;
 ...
var
  StCan : TStyleCanvas;
...
stCan.OnMouseMove := @MMove;
...

In one of the project it says that "OnMouseMove" is an unknown identifier while in the other no such error.
The only difference is that in the error-giving project the TStyleCanvas is defined in another unit, while in the running project it is define in the main unit. I think this is the problem. but, Why?
The mousemove event path : TControl > TWinControl > TCustomControl

Does anyone know what the problem is?

Thank u.

[theo]

It's protected in TControl. Do this in your TStyleCanvas:

Code: [Select]

type
  TStyleCanvas = class(TCustomControl)
  public
    SRC : HDC;
    procedure EraseBackground(DC: HDC); override;
    procedure Paint; override;
  published
    property OnMouseMove; //<-raise to published
  end;


[Peiman]

Thank u.
It worked.
But, as I said, the definition of the both "TStyleCanvas"es were the same. I mean none of them had "published". So , why one of them worked without this declaration while the other didn't? Was there any compiler option for that?

[theo]

Classes in the same unit can access protected and private methods and variables of each other. It has always been this way in Delphi too.