PE_BEGINDATA
Sent to the
window specified by the htrgTarget member of the TARGET structure the first time
any pen data is directed toward that window. Submessage of WM_PENEVENT.
Parameters
wParam
PE_BEGINDATA
lParam
Address of a TARGET
structure.
Comments
A target
window can initialize the dwData member of the TARGET structure
with a handle to pen data (HPENDATA), a handwriting recognition object (HRC),
or some private data type. If dwData is an HPENDATA object, the HPENDATA
object should be in standard scale with no OEM data. For example, the HPENDATA
object can be created as follows:
CreatePenDataEx(NULL, PDTS_STANDARDSCALE, CPD_TIME,
0);
The target
window informs Windows of the type of data in the dwData member of the TARGET structure by returning
LRET_HPENDATA, LRET_HRC, or LRET_PRIVATE (or LRET_DONE). If the application
lets the message fall down to the Windows DefWindowProc function, then the
function creates a handwriting recognition object (HRC) for this target.
The window
can ignore all input except gestures. In this case, it must create a
handwriting recognition object and customize it to recognize only gestures.
For an example
of how an application can handle PE_BEGINDATA, see the source code for PENAPP.C
in Chapter 7, A Sample Pen Application.
See Also