DdfBitmap - Example Code

After initializing a DDF buffer with DdfInitialize, the example obtains a device context (DevOpenDC), creates a presentation space (GpiCreatePS), and loads a bit map (GpiLoadBitmap). It then uses DdfBitmap to place a reference to the bit map in the DDF buffer. For a more detailed example and discussion of initializing DDF, see the DdfInitialize sample.

#define INCL_WINWINDOWMGR       /* General window management     */
#define INCL_WINMESSAGEMGR      /* Message management            */
#define INCL_GPICONTROL         /* Basic PS control              */
#define INCL_GPIBITMAPS         /* Bit maps and Pel Operations   */
#define INCL_GPIPRIMITIVES      /* Drawing Primitives/Attributes */
#define INCL_DDF                /* Dynamic Data Facility         */
#include <os2.h>
#include <pmhelp.h>

#define ACVP_HAB  12
#define BM_HPS    16
#define BM_HDC    20
#define BM_HWND   24
#define ID_LEFT   255

MRESULT WindowProc( HWND hwnd, ULONG ulMsg, MPARAM mp1, MPARAM mp2 )
{
    HWND    hwndParent;     /* parent window                        */
    HWND    hwndInstance;   /* help instance window                 */
    HDDF    hDdf;           /* DDF handle                           */
    HDC     hdc;            /* device context handle                */
    HPS     hps;            /* presentation space handle            */
    HAB     hab;            /* anchor block handle                  */
    SIZEL   sizel = {0L,0L};/* size of new PS                       */
    HBITMAP hBitmap;        /* bit map handle                       */
    HMODULE hModule;        /* module handle                        */

    switch( ulMsg )
    {
    case HM_QUERY_DDF_DATA:
        hwndParent = WinQueryWindow( hwnd, QW_PARENT );
        hwndParent = WinQueryWindow( hwndParent, QW_PARENT );
        hwndInstance = (HWND)WinSendMsg( hwndParent, HM_QUERY,
                                 MPFROMSHORT( HMQW_INSTANCE ), NULL );

        /* Allocate 1K Buffer (default)  */
        hDdf = DdfInitialize(
                       hwndInstance,  /* Handle of help instance */
                       0L,            /* Default buffer size     */
                       0L             /* Default increment       */
                       );

        if (hDdf == NULLHANDLE)       /* Check return code       */
        {
            return (MRESULT)FALSE;
        }

        /* get module handle for bit map */
        DosQueryModuleHandle("bitmap", &hModule);
        if (hModule == NULLHANDLE)
        {
            return (MRESULT)FALSE;
        }

        /* get hab for this window */
        if ((hab = (HAB)WinQueryWindowULong(hwnd, ACVP_HAB)) == NULLHANDLE)
        {
            return (MRESULT)FALSE;
        }

        /* create a device context */
        if ((hdc = DevOpenDC(hab, OD_MEMORY, "*", 0L,
                            (PDEVOPENDATA)NULL, (HDC)NULL)) == NULLHANDLE)
        {
           return (MRESULT)FALSE;
        }

        /* save hdc in reserved word */
        WinSetWindowULong(hwnd, BM_HDC, (ULONG)hdc);

        /* create a noncached micro presentation space */
        /* and associate it with the window */
        if ((hps = GpiCreatePS(hab, hdc, &sizel,
                   PU_PELS | GPIF_DEFAULT
                   | GPIT_MICRO | GPIA_ASSOC)) == NULLHANDLE)
        {
           return (MRESULT)FALSE;
        }

        /* save hps in reserved word */
        WinSetWindowULong(hwnd, BM_HPS, (ULONG)hps);

        /* Load the Bit map to display */
        if ((hBitmap = GpiLoadBitmap(hps, hModule, ID_LEFT, 300L,
                                     300L)) == NULLHANDLE)
        {
            return (MRESULT)FALSE;
        }

        /* save bit map hwnd in reserved word */
        WinSetWindowULong(hwnd, BM_HWND, (ULONG)hBitmap);

        /* Display the bit map align left */
        if (!DdfBitmap(hDdf, hBitmap, ART_LEFT))
        {
            return (MRESULT)FALSE;
        }

        return (MRESULT)hDdf;

    case WM_CLOSE:
        /* release PS, DC, and bit map */
        GpiDestroyPS((HPS)WinQueryWindowULong(hwnd, BM_HPS));
        DevCloseDC((HDC)WinQueryWindowULong(hwnd, BM_HDC));
        GpiDeleteBitmap((HBITMAP)WinQueryWindowULong(hwnd, BM_HWND));
        WinDestroyWindow(WinQueryWindow(hwnd, QW_PARENT));
        return (MRESULT)TRUE;
    }
}