Q I found the following declaration in
Script.h:
extern PASCAL Boolean IsCmdChar(const EventRecord
*eventRecord, short test)
FOURWORDINLINE(0x2F3C, 0x8206, 0xFFD0, 0xA8B5);
I can't seem to find any documentation for this call; does such
documentation exist? If this is what I think it is, it could be very
useful.
A Whoops -- thanks for pointing this out. That
routine was introduced with System 7. Here's a description of the
routine:
FUNCTION IsCmdChar(keyEvent: EventRecord; testChar:
INTEGER): BOOLEAN;
This function tests whether the Command key is being pressed in
conjunction with another key (or keys) that could generate
testChar for some combination of Command up or down and
Shift up or down. This accommodates European keyboards that may have
testChar as a shifted character, and non-Roman keyboards
that will only generate testChar if Command is down.
It's most useful for testing for Command-period, but it can test for
command-AnyCharacter.
The caller passes in the event record, which is assumed by the
function to be an event record for a key-down or auto-key event with
the Command key down. The caller also passes in the character to be
tested for (for example, "."). The function returns TRUE
if testChar is produced with the current modifier keys,
or if it would be produced by changing the current modifier key bits
in either or both of the following ways:
- turning the Command bit off
- toggling the Shift bit
A sample of how you might use this function:
OSErr HandleKeys (EventRecord *eventPtr) {
OSErr err = noErr;
if (eventPtr->modifiers & cmdKey) {
if (IsCmdChar (eventPtr, '.')) {
gStop = true;
} else {
err = DispatchMenuChoice (MenuKey (eventPtr->message & charCodeMask));
}
}
return err;
}
|
Note: The IsCmdChar function returns the
0xFF to represent true. IsCmdChar
does not return 1, so make sure that your code works
correctly when 0xFF is returned. Don't test the function
result against whavever happens to be defined as
true by your development environment unless
you know that true has been defined to be 0xFF.
MacTypes.h defines true == 1,
which would cause the expression to always evaluate as
false.
|
[Jul 06 1998]
|
