Re: [boost] Re: C++ GUI - another view

From: John Torjo (john.lists_at_[hidden])
Date: 2004-09-22 09:10:11

David Abrahams wrote:

> Matt S Trentini <matt_trentini_at_[hidden]> writes:
> 
> 
>>John Torjo wrote:
>>
>>
>>>Could you elaborate a bit? What do you think is the window handle
>>>limit under win32?
>>
>>I think that perhaps Mathew is talking about the GDI object limit.  At
>>least under Windows 2000 and earlier versions (I'm not sure about XP)
>>there is a firm limit of 16K handles that can be allocated system wide
>>- 
>>regardless of your particular specs (ie adding memory does not
>>help). When this limit is reached weird stuff [1] happens which can
>>only be fixed by a reboot.
>>
>>Any object that allocates a handle under Windows (pens, brushes, dc's,
>>etc) consume those resources and if you've got a graphically intense
>>GUI using a greedy GUI library (ie one that holds it's handles for a
>>long duration) that limit isn't too hard to break.
> 
> 
> Yes, IIRC, that's why a spreadsheet implemented with a Window per cell
> will have a very small maximum size, and why ultimately, any robust
> window framework under Win32 has to have an abstraction layer that
> makes the issue of whether or not there's a real "windows window"
> running the show in any given pane disappear.

Why not just use an existing list control or grid?

Best,
John

-- 
John Torjo
-- john_at_[hidden]
Contributing editor, C/C++ Users Journal
-- "Win32 GUI Generics" -- generics & GUI do mix, after all
-- http://www.torjo.com/win32gui/
-- v1.4 - save_dlg - true binding of your data to UI controls!
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