|
|
PATH Mac OS 8 and 9 Developer Documentation
> Human Interface Toolbox
> Control Manager
>
|
Programming With the Mac OS 8.5 Control Manager
|
If you implement a custom control definition function, when the Control Manager passes the message kControlMsgGetRegion in your control definition function's message parameter, it also passes a pointer to a structure of type ControlGetRegionRec in the param parameter. Your control definition function is responsible for setting the region field of the ControlGetRegionRec structure to the region that contains the control part which the Control Manager specifies in the part field.
See Control Definition Message Constants for more details on the kControlMsgGetRegion message.
struct ControlGetRegionRec
{
RgnHandle region;
ControlPartCode part;
};
typedef struct ControlGetRegionRec ControlGetRegionRec;
typedef ControlGetRegionRec* ControlGetRegionPtr;