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."