Fwd: Comment to "ListBox Keyholes"

>From: Peter Manfred <[email protected]>
>To: "'smeyers-Q9ZaqOuDrMJWk0Htik3J/[email protected]'" <[email protected]>
>Subject: Comment to "ListBox Keyholes"
>Date: Wed, 30 Jul 2003 14:08:32 +0200
>X-Mailer: Internet Mail Service (5.5.2653.19)
>
>Hello, Scott Meyers!
>
>In the chapter "ListBox Keyholes", wrapped around edge between pages 16 and 
>17, you write:
>
>> We can divide listboxes into two categories. Static listboxes are 
>> those whose contents are fixed and known before runtime. State-selection 
>> listboxes (Figure ??-4), month selection listboxes (Figure ??-5), drive 
>> letter selection listboxes (Figure ??-6), and day selection listboxes for 
>> a particular month (Figure ??-13) are examples of static listboxes.
>
>The selection of drive letters is definitely not fixed even at runtime. 
>Under DOS and Windows, you can create network drives and SUBSTitute local 
>paths with drives *anytime*. ZIP-Drives, memory sticks/cards, digital 
>cameras and similar devices ususally show themselves as new drives; at 
>least with USB devices this can happen at runtime. 
>
>The maximum number of drives is commonly assumed to be constant, as drive 
>letters may range from A: to Z:. Alas I dimly remember some undocumented 
>feature that allows drive letters like ':, so I wouldn't rely on a maximum 
>of 26 drives. (That really *is* a tick as drive letter!)
>
>To comment on the definition of fixed size list boxes: I think the 
>fixedness of the content isn't the crucial point, because a listbox
>usually reduces its size if there is less to display. What matters is 
>the maximum number of items. If you know this number, you can define 
>the listbox to cover that size - Et violin! No keyhole possible! 
>(Except if you forgot to count one or more items - you already mention 
>such a case on the top of page 7.)
>
>In the hope it's useful,
>
>	M.Peter (aka Freddy)
>
>	[email protected]
>	or [email protected]