Scroll events

Andreas Raab andreas.raab at
Fri Mar 18 21:36:03 UTC 2005

Hi John,

John M McIntosh wrote:
> I'm sure this is a change from our original thoughts to generate  
> unicode values for the keydown/keyup.

It's certainly not a change from my original thoughts (though I might 
have expressed them inadequately ;-) It has always been my intention to 
make keyDown/keyUp events so that (in theory) the image could construct 
the corresponding keyChar events itself. The only reason we wouldn't do 
this is pure lazyness (and the need to know a few things from the OS in 
order to make the integration smooth).

> I'll note you could be using a  
> input palette and not a keyboard device so you won't get any key  
> up/down events, and you imply that you are supplying unicode values for  
> the keystroke, versus the historical MacRoman? So how does a  unicode  
> character flow up in Windows?

Right now, no Unicode gets up to Windows. It really depends on what we 
decide to do with it (see my other post - I think having a new event 
type is the easiest and cleanest way to deal with the issue).

> For the most part I am using the unix keyboard logic for os-x to track  
> the key up/down strokes, so given your accented character
> a) we remember the keyDown,
> b) translation input services gives us the unicode for  á (accented-a)  
> which I generate as a keyDown  unicode. This is after translation  
> services has digested all the keystrokes and made a decision on what it  
> all means.
> c) I translate that into the macroman character for  á (accented-a)  
> which could depending on your language choice be different than the  
> unicode, which I generate as a KeyChar
> d) when the key goes up I have remembered the unicode for  á  
> (accented-a) which I generate as a keyUp.
> *If input services gives us a unicode, or input  palette services give  
> us a unicode for which there is no MacRoman translation then the  
> keyChar value is unicode. I'll note that input  palette services can  
> give us a string of unicode which is translated into synthetic  
> keydown/keychar/keyup values.
> It could be possible under os-x to generate the keydown/keyup and  
> keychar as suggested but I'm not sure what that would break.  The only  
> information I have is the keycodes which are values mapped to keys and  
> depend on the keyboard used and would require a translation table in  
> smalltalk.

I'd say let's just list that unicode in a new event and everything 
should be pretty much fine.

   - Andreas

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