CS6::canceling a keystroke

Question

Hi
I have an edit box that may accept only alpha characters. I added my own iplementantion of IID_IEVENTHANDLER on my kTextEditBoxWidgetBoss.
I get the event but, I do not know how to cancel, I try this code, it seems to work in windows, but it fails to mac.
how should I do it?
Thank you
bool16 CAlphaEventHandler::KeyCmd(IEvent* pEvent)
    if (pEvent == NULL )
        return kFalse ;
    const SysChar    nCharCode = pEvent->GetChar();
    if (
        ((nCharCode >= 'a' ) && (nCharCode <= 'z' ) ) ||
        ((nCharCode >= 'A' ) && (nCharCode <= 'Z' ) )
        return PlatformEditBoxEventHandler::KeyDown(pEvent); 
    pEvent->SetChar(0 );
    return PlatformEditBoxEventHandler::KeyDown(pEvent);

Answer 1

jcs--
Unfortunately, SetChar()'s documentation hasn't been accurate for many, many versions. Instead, just replace PlatformEditBoxEventHandler's KeyDown() with one that checks for unwanted characters and filters them out by invoking
Utils<IEventUtils>()->RemoveNextKeyCmd(pEvent)
pEvent->SetSystemHandledState(IEvent::kDontCall);
return kTrue; // indicate 'handled'
Keys that you want to keep should be passed along to the original (base class's) KeyDown() like you're doing in your code snippet above. This works on both OSes and in CS5 thru CC.
Oh, and be careful not to filter out virtual keys like left/right arrow, Enter, etc. :-)
Hope this helps.
chris