WindowProc Subclassing

[schu-r]

Hi

I Used to Subclass WindowProc for some Controls in Delphi to Write my own WindowHandler (of course I called the Base Window Handler after it) just to react on some Windowmessages.

But in Lazarus i cannot change the WindowProc Handler.


Is there a different Way to get to the window Messages of an individual Control?

[Vincent Snijders]

You still can subclass the window procedure, using Windows.SetWindowLong.

[felipemdc]

You can just override the default WindowProc, like this, on your TForm window:

  TMainWindow = class(TForm)
     ......
  public
{$IFDEF Win32}
    procedure WndProc(var Message : TMessage); override;
{$ENDIF}
  end;

[schu-r]

I need to set them at Runtime. Because I look at the Controls of a Form and then I decide which Controls to subclass. The code Searches all the Controls and Subclasses them.
This is a kind of LayoutManager similar to Java. It works so far in Delphi (can change the Look and Feel and even the behaviour of some Fields).