[lazarus] Notebook pages LM_SETITEMINDEX

Mattias Gaertner nc-gaertnma at netcologne.de
Mon Dec 16 04:18:07 EST 2002

On Sun, 15 Dec 2002 23:45:25 +0100
"Vincent Snijders" <vslist at zonnet.nl> wrote:

> Hi all,
> I am working on the notebook pages in win32 and I have a question.
> In line 662 of CustomNotebook.inc (part of TCustomNotebook.SetPageIndex)
> FPageIndex is set to 0 if it is smaller than zero, just before sending the
> LM_SETITEMINDEX message to the interface.
> The problem is that this message is also send on destroying pages

I changed that.

> and now it
> is difficult to see, if the interface needs to show the a tabpage. Why
> isn't -1 not a valid value for a PageIndex? 

IMO, if a notebook has pages, then there is also a top page. Gtk thinks the
same (it will select the last as default). I didn't know, that Delphi and
win32 supports no active page. For compatibility I removed the auto

> Why can't -1 be sent as a page
> index? I seem to have no way of detecting an empty notebook, because
> Pages.Count is still 1.


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