KeycodeFromUniChar

Hi All,

The program I’m trying to create is to increase accessibility to text fields so for a given set of preset strings the user can click a button and the app will post that string (or single key) to whichever app is active. I found the method CGPostKeyboardEvent but it requires a keycode as opposed to a string. So in theory I thought I would iterate through each character in my string and “post” them separately. I’m trying to figure out how to get the keycode for a given character.

Thanks in advance for any help.

This is not exactly what you asked for (nor it is a perfect solution), but it’s close enough that I’m sure it will be of some help to you. I got most of this code elsewhere, from a google cache of an online forum post I can’t find anymore (that was written in french, and loosely translated by me). I wish I could take credit, but somebody smarter than me figured it out.

BOOL Ascii2Virtual(char pcar, BOOL *pshift, BOOL *palt, char *pkeycode) { KeyboardLayoutRef keyboard; const void *keyboardData; // keyboard layout data UInt16 nbblocs; char *modblocs, *blocs, *deadkeys; int ix, ifin, numbloc, keycode;

BOOL shift, alt;

// r�cup�ration du clavier courant
// get the current keyboard
if(KLGetCurrentKeyboardLayout(&keyboard)) return NO;

// r�cup�ration de la description (keyboard layout) du clavier courant
// get the description of the current keyboard layout
if(KLGetKeyboardLayoutProperty(keyboard, kKLKCHRData, &keyboardData)) return NO;

// r�cup�ration du pointeur de d�but des num�ros de blocs pour chaque combinaison de modifiers
// get pointer early numbers of blocks for each combination of modifiers
modblocs = ((char *)keyboardData) + 2;

// r�cup�ration de nombre de blocs keycode->ascii
// get number of blocks keycode->ascii
nbblocs = *((UInt16 *)(keyboardData + 258));

// r�cup�ration du pointeur de d�but des blocs keycode->ascii
// get pointer early blocks keycode-> ascii
blocs = ((char *)keyboardData) + 260;

// on d�termine la taille de toutes les tables keycode->ascii � scanner
// determining the size of all tables keycode-> ascii a scanner
ifin = nbblocs*128;

// on d�termine le pointeur de d�but de la tables des dead keys
// determining pointer early in the tables of dead keys
deadkeys = blocs+ifin;

// maintenant on parcourt les blocs keycode->ascii pour retrouver le car ascii
// Now it runs blocks keycode-> ascii to find the car ascii
for (ix=0; ix<ifin; ix++)
{
    if (blocs[ix]==pcar)
    {
        // car ascii trouv� : il faut d�terminer dans quel bloc (num�ro du bloc) il se trouve
        // found ascii value: now we must determine which block it is
        keycode = ix & 0x7f; // 0111 1111 mask
        numbloc = ix >> 7;
        break;
    }
}

// car non trouv� : on termine (avec erreur)
// not found: bail out (error)
if (ix >= ifin) return NO;

// � partir du num�ro de bloc, il faut retrouver la combinaison de modifiers utilisant ce bloc
// from block number, we must find the combination of modifiers using this block
for (ix=0; ix<15; ix++)
{
    // on ne traite pas si les modifiers ne sont pas "majuscule" et "option"
    // it does not address whether the modifiers are not "capital" and "option"
    if (ix&1 || ix&4) continue;
    
    // combinaison de modifiers trouv�e pour le bloc
    // Combining modifiers found for the block
    if (modblocs[ix]==numbloc)
    {
        shift = (ix&2) ? YES : NO;
        alt   = (ix&8) ? YES : NO;
        break;         
    }
}

// combinaison modifiers non trouv� : on termine (avec erreur)
// combination modifiers not found: bail
if (ix>=15) return NO;

// mise � jour des param�tres
// save our parameters
*pkeycode=keycode;
*pshift=shift;
*palt=alt;

return YES; }

Don’t ask me how the guy who wrote that figured it out, but I can assure you that it does indeed work :P You could then write a simple method to get every character in a string and send them.

(int)keyCodeForCharacter: (NSString*)character { if(![character length]) return -1;

char code; BOOL shift, alt; if(Ascii2Virtual( (char)[character characterAtIndex: 0], &shift, &alt, &code)) { return code; } return -1; }

I hope this helps you. - Jon

CocoaDev