From Forum Nokia Wiki

The Nokia N95's slider sends the following key events:

(1) Open keyboard slider
aType = 0x0003, iCode = 0x0000, iScanCode = 0x00ac  (EStdKeyDevice8)
aType = 0x0002, iCode = 0x0000, iScanCode = 0x00ac
 
(2) Close keyboard slider
aType = 0x0003, iCode = 0x0000, iScanCode = 0x00ad  (EStdKeyDevice9)
aType = 0x0002, iCode = 0x0000, iScanCode = 0x00ad
 
(3) Open music slider
aType = 0x0003, iCode = 0x0000, iScanCode = 0x00a8  (EStdKeyDevice4)
aType = 0x0002, iCode = 0x0000, iScanCode = 0x00a8
 
(4) Close music slider
aType = 0x0003, iCode = 0x0000, iScanCode = 0x00a9  (EStdKeyDevice5)
aType = 0x0002, iCode = 0x0000, iScanCode = 0x00a9

Take care! In the S60 SDK (eikon.hrh), there are some helpful ids defined:

#define EKeyGripOpen EKeyDevice4
#define EKeyGripClose EKeyDevice5
#define EKeyTwistOpen EKeyDevice8
#define EKeyTwistClose EKeyDevice9

But they do not help. There is never a iCode sent. The slider only sends iScanCode events. There is no EStdKeyGripOpen defined, so you have to put the generic defines from Symbian into your code.