Visual Basic Toolbox/Visual Basic Toolbox (P.I.E.)(1996).ISO/clocks/ttcode/modblast.c

C/C++ Source or Header | 1994-10-20 | 19.2 KB | 657 lines

//---------------------------------------------------------------------------
// modblast.c
//---------------------------------------------------------------------------
// Contains control procedure for ModBlaster control
//---------------------------------------------------------------------------

#define  NOCOMM
#include <windows.h>

#include <vbapi.h>
#include <string.h>
#define CTL_DATA
#include "modblast.h"

//---------------------------------------------------------------------------
// Global Variables
//---------------------------------------------------------------------------
HANDLE hmodDLL;
CONTROLSTUFF controls[MAX_MSGBLASTERS];
HANDLE taskDevEnvironment = NULL;


//---------------------------------------------------------------------------
// Utility Functions - added by BJ 1/15/94
//---------------------------------------------------------------------------
WORD FAR PASCAL _export mbLoWord(DWORD dword)
{
    return (WORD)dword;
}

WORD FAR PASCAL _export mbHiWord(DWORD dword)
{
    return (WORD)(dword >> 16);
}

WORD FAR PASCAL _export mbGetControlIndex(HWND hwnd)
{
    DWORD index;
    HCTL hCtl;
    if ((hCtl = VBGetHwndControl(hwnd)) &&
        (VBGetControlProperty(hCtl, IPROP_STD_INDEX, (LPVOID)&index) == 0))
        return (WORD)index;
    else
        return (WORD)-1;
}

ULONG FAR PASCAL _export mbSetControlFlags(HWND hwnd, ULONG mask, ULONG value)
{
    return VBSetControlFlags(VBGetHwndControl(hwnd), mask, value);
}

//---------------------------------------------------------------------------
// MsgBlaster Control Procedure
//---------------------------------------------------------------------------
LONG FAR PASCAL _export MsgBlasterCtlProc(HCTL hctl, HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
{
      switch (msg)
    {

    case WM_NCCREATE:
    {
        int i;
        // deref MsgBlaster control struct now - valid until we call VB procedure (BJ)
        PMSGBLASTER lpMsgBlaster = LpblastDEREF(hctl);

        // Look for an open slot in the array and save the hctl
        for(i = 0; i < MAX_MSGBLASTERS; i++)
        {
            if(controls[i].hctlMain == NULL)
            {
                controls[i].hctlMain = hctl;
                break;
            }
        }

        // If users are trying to use this many blasters, then they are
        // probably doing something wrong. Besides, using 25 blasters would
        // slow down the entire system
        if (i == MAX_MSGBLASTERS)
        {
            MessageBox(hwnd, "Too many message blasters", "Error!", MB_OK);
            return(0);
        }

        // make sure that the hWndTargets are zeroed out.
        lpMsgBlaster->hWndTarget = NULL;

        // initialize the passage var to pass msgs onto the origproc
        // after firing the event. This is the default behavior.
        // There was a bug here - replaced MAX_MSGBLASTERS with MAX_TRAPPABLEMSGS (BJ)
        for(i = 0; i < MAX_TRAPPABLEMSGS; i++)
            lpMsgBlaster->MsgPassage[i] = 1;

          VBSetControlProperty(hctl, IPROP_MSGBLASTER_ABOUTBOX,
              (LONG)(LPSTR)"Click on \"...\" for the About Box ---->");

    }
    break;

    case VBM_SETPROPERTY:
        switch(wp)
        {
        case IPROP_MSGBLASTER_HWNDTARGET:
        {
            int i, j;

            // we only process this message if we are in run mode
            if (VBGetMode() != MODE_DESIGN)
            {
                // deref MsgBlaster control struct now - valid until we call VB procedure (BJ)
                PMSGBLASTER lpMsgBlaster = LpblastDEREF(hctl);

                // find the next slot and save the hWndTarget
                for(i = 0; i < MAX_MSGBLASTERS; i++)
                {
                    if(controls[i].hctlMain == hctl)
                    {
                        // Check to see if this blaster is already being
                        // used to subclass a control
                        // if it is, un-subclass it.
                        // This could happen when the vb programmer changes
                        // the target control at run time
                        if(controls[i].hWndTarget) {
                            UnSubClass(controls[i].hWndTarget,hctl);
                            // initialize messages and passage when target changes (BJ)
                            for(j = 0; j < MAX_TRAPPABLEMSGS; j++) {
                                lpMsgBlaster->MsgList[j] = 0;
                                lpMsgBlaster->MsgPassage[j] = 1;
                            }
                        }

                        controls[i].hWndTarget = (HWND)lp;
                        break;
                    }
                }

                // sublcass the target control
                // only if target not == NULL (BJ)
                if ((HWND)lp != NULL && !FSubClass((HWND)lp))
                    MessageBox(hwnd, "Unable to subclass control", "Error", MB_OK);
            }
        }
        return 0L;

        case IPROP_MSGBLASTER_MSGLIST:
        {
            // This is where we store the list of messages to trap
            // normally, the vb programmer will load this in the
            // form load event.
            LONG i;
            LPDATASTRUCT lpDs = (LPDATASTRUCT)lp;

            i = lpDs->index[0].data;

            // I put an arbitrary limit on the number of messages
            // that could be trapped. My think is that they really shouldn't
            // be doing a lot of message processing in VB.
            if (i < 0 || i >= MAX_TRAPPABLEMSGS)
                return ERRBADINDEX;

                        LpblastDEREF(hctl)->MsgList[i] = (UINT)lpDs->data;
            return 0L;
        }

        case IPROP_MSGBLASTER_MSGPASSAGE:
        {
            // This property determines how each message will be processed
            // There are 3 valid possibilities; -1, 0, 1.
            // -1 means preprocess the message. This means pass it on to the
            //      VBDefControlProc first
            // 0  means eat the message. i.e. never pass it on
            // 1 means pass the message on after firing the event
            // This is the default.
            LONG i;
            LPDATASTRUCT lpDs = (LPDATASTRUCT)lp;

            i = lpDs->index[0].data;
            if (i < 0 || i >= MAX_TRAPPABLEMSGS)
                return ERRBADINDEX;

            LpblastDEREF(hctl)->MsgPassage[i] = (SHORT)lpDs->data;
            return 0L;
        }

    }
    break;


    case VBM_GETPROPERTY:
        switch(wp)
        {
        case IPROP_MSGBLASTER_MSGLIST:
        {
            LONG i;
            LPDATASTRUCT lpDs = (LPDATASTRUCT)lp;

            i = lpDs->index[0].data;
            if (i < 0 || i >= MAX_TRAPPABLEMSGS)
                return ERRBADINDEX;

                        lpDs->data = (LONG)LpblastDEREF(hctl)->MsgList[i];
            return 0L;
        }
        case IPROP_MSGBLASTER_MSGPASSAGE:
        {
            LONG i;
            LPDATASTRUCT lpDs = (LPDATASTRUCT)lp;

            i = lpDs->index[0].data;
            if (i < 0 || i >= MAX_TRAPPABLEMSGS)
                return ERRBADINDEX;

            lpDs->data = LpblastDEREF(hctl)->MsgPassage[i];
            return 0L;
        }
        case IPROP_MSGBLASTER_HWNDTARGET:
        {
            LONG i;
            LPDATASTRUCT lpDs = (LPDATASTRUCT)lp;

            i = lpDs->index[0].data;
            if (i < 0 || i >= MAX_TRAPPABLEMSGS)
                return ERRBADINDEX;

            lpDs->data = LpblastDEREF(hctl)->hWndTarget;
            return 0L;
        }

        } // end of switch
        break;

        case VBM_INITPROPPOPUP:
               if(wp == IPROP_MSGBLASTER_ABOUTBOX)
            {
                HWND hwndList = (HWND)LOWORD(lp);
                return (LONG)HwndInitAboutBox();
            }
            break;
        case IPROP_MSGBLASTER_ABOUTBOX:
            // force a repaint
            InvalidateRect(hwnd, NULL, FALSE);
            break;

        case WM_NCDESTROY:
            if(LpblastDEREF(hctl)->hszAbout)
                VBDestroyHsz(LpblastDEREF(hctl)->hszAbout);
            break;

        case WM_DESTROY:
        {
            int i;

            // find which control we are dealing with
            for(i = 0; i < MAX_MSGBLASTERS; i++)
                if(controls[i].hctlMain == hctl)
                    break;

            // ****>>> We *must* unsubclass the hwndTarget when
            // this hctl goes away!
            UnSubClass(controls[i].hWndTarget,hctl);

            controls[i].hWndTarget = NULL;
            controls[i].hctlMain = NULL;
        }
        break;
    }
    return VBDefControlProc(hctl, hwnd, msg, wp, lp);
}


//---------------------------------------------------------------------------
// Sub class routine for target control window proc.
//---------------------------------------------------------------------------
LONG FAR PASCAL _export SubClassProc(HWND hwnd, UINT msg, WPARAM wp, LPARAM lp)
{
      LONG rc;
      int  i, j;
    UINT m;
    HCTL hctlMain;

    // find the correct hctlMain
    // I could have called FindhctlMain, but I wanted to avoid the overhead
    // we need the most speed we can get in this routine.
    for(j = 0; j < MAX_MSGBLASTERS; j++)
        if(controls[j].hWndTarget == hwnd)
            break;

    // The first part of this if is a sanity check
    if(j == MAX_MSGBLASTERS)
        MessageBox(hwnd, "Big trouble. We're gonna die.", "TROUBLE", MB_OK);
    else
        hctlMain = controls[j].hctlMain;

        for (i=0; i < MAX_TRAPPABLEMSGS; i++)
    {

        // Get out of the loop if hctlMain is no longer valid
        // ****>>> Since you fire an event, it is possible for hctlMain to
        // disappear during that event, so you must check to see if hctlMain
        // is still non-NULL.  This is also why I added the NULLing out of
        // this variable to the WM_DESTROY case.
        if (!hctlMain)
              break;

        // ****>>> Firing an event invalidates pMsgBlaster!!!!
        // You MUST deref it each time through this loop!!!
                m = LpblastDEREF(hctlMain)->MsgList[i];

        // Get out of the loop if no more messages
        if (!m)
              break;

        if (msg == m)
        {
            int eat;

            // now that we have a hit, determine if we should pass the
            // msg on to the orig proc first, last or
            // do we eat the msg entirely
            eat = LpblastDEREF(hctlMain)->MsgPassage[i];
            switch(eat)
            {
            case -1: // call the orig proc first
                rc = CallWindowProc(LpblastDEREF(hctlMain)->lpfnOrigProc,
                                hwnd, msg, wp, lp);
                rc = FireMessage(hctlMain, msg, wp, lp, rc);
                if (msg == WM_DESTROY)
                {
                    MessageBox(hwnd,
                        "Can't call original proc with WM_DESTROY prior to firing event.",
                        "Error", MB_OK);
                    break;
                }
                return rc;

            case 0: // eat the message
                rc = FireMessage(hctlMain, msg, wp, lp, rc);
                if (msg == WM_DESTROY)
                {
                    MessageBox(hwnd,
                        "Can't eat WM_DESTROY message.",
                        "Error", MB_OK);
                    break;
                }
                return rc;

            case 1: // pass it on afterward
                rc = FireMessage(hctlMain, msg, wp, lp, rc);
                break;

            case 2: // pass it on afterward - MAYBE - BJ
                rc = FireMessage(hctlMain, msg, wp, lp, rc);
                // if the return code is 0 then the message has been handled - BJ
                if (rc == 0) return rc;
                break;

            default:
                MessageBox(hwnd,
                    "Default case in passage test. Should never get.",
                        "Error", MB_OK);
                break;
            }
        }
    }

      // Call the original Window Procedure
      rc = CallWindowProc(LpblastDEREF(hctlMain)->lpfnOrigProc, hwnd, msg, wp, lp);

      // ****>>> Strictly speaking, it is not necessary to unsubclass this window
      // since it is being destroyed, but UnSubClass() does *need* to reset the
      // necessary global variables, and modular programming says we shouldn't
      // do that from here, when UnSubClass() can do that for us...
      if (msg == WM_DESTROY)
        UnSubClass(hwnd, hctlMain);

      return rc;
}


//--------------------------------------------------------------------------
// Fire the msg event
//--------------------------------------------------------------------------
LONG NEAR FireMessage(HCTL hctl, UINT m, WPARAM wp, LPARAM lp, LONG rc)
{
    MSGPARAMS p;
    UINT mval = m;

    p.MsgVal = &mval;
    p.wParam = ℘
    p.lParam = &lp;
    p.lRetVal= &rc;

    VBFireEvent(hctl, IEVENT_MSGBLASTER_MSG, &p);
    return rc;
}


//---------------------------------------------------------------------------
// Register custom control.  This routine is called by VB when the custom
// control DLL is loaded for use.
//---------------------------------------------------------------------------
BOOL FAR PASCAL _export VBINITCC(USHORT usVersion, BOOL fRuntime)
{
    // Avoid warnings on unused (but required) formal parameters
    fRuntime  = fRuntime;

    // Register control(s)
    if (usVersion < VB200_VERSION)
      return FALSE;

    // Register popup class if this is from the development environment.
    if (!fRuntime)
    {
    WNDCLASS class;

    class.style        = 0;
    class.lpfnWndProc   = AboutBoxProc;
    class.cbClsExtra    = 0;
    class.cbWndExtra    = 0;
    class.hInstance     = hmodDLL;
    class.hIcon            = NULL;
    class.hCursor        = NULL;
    class.hbrBackground = NULL;
    class.lpszMenuName  = NULL;
    class.lpszClassName = CLASS_ABOUTBOX;

    if (!RegisterClass(&class))
        return FALSE;

    // Remember the task associated with the development environment
    taskDevEnvironment = GetCurrentTask();

    }


    return VBRegisterModel(hmodDLL, &modelMsgBlaster);
}


//---------------------------------------------------------------------------
// Provide custom control model information to host environment.
//---------------------------------------------------------------------------
LPMODELINFO FAR PASCAL _export VBGetModelInfo(USHORT usVersion)
{
    if (usVersion < VB200_VERSION)
        return NULL;
    else
        return &modelinfoMsgBlaster;
}


//---------------------------------------------------------------------------
// Initialize library.    This routine is called when the first client loads
// the DLL.
//---------------------------------------------------------------------------
int FAR PASCAL LibMain(HANDLE hModule, WORD wDataSeg, WORD cbHeapSize, LPSTR lpszCmdLine)
{
    // Avoid warnings on unused (but required) formal parameters
    wDataSeg    = wDataSeg;
    cbHeapSize    = cbHeapSize;
    lpszCmdLine = lpszCmdLine;

    hmodDLL = hModule;

    return 1;
}

//---------------------------------------------------------------------------
// Unregister the property popup , if this unload
//    is from the development environment.
//---------------------------------------------------------------------------

VOID FAR PASCAL _export VBTERMCC()
{
    // Unregister popup class if this is from the development environment
    if (taskDevEnvironment == GetCurrentTask())
    {
        UnregisterClass(CLASS_ABOUTBOX, hmodDLL);
        taskDevEnvironment = NULL;
    }
}

//---------------------------------------------------------------------------
// WEP
//---------------------------------------------------------------------------
// C7 and QCWIN provide default a WEP:
//---------------------------------------------------------------------------
#if (_MSC_VER < 610)

int FAR PASCAL WEP(int fSystemExit);

//---------------------------------------------------------------------------
// For Windows 3.0 it is recommended that the WEP function reside in a
// FIXED code segment and be exported as RESIDENTNAME.  This is
// accomplished using the alloc_text pragma below and the related EXPORTS
// and SEGMENTS directives in the .DEF file.
//
// Read the comments section documenting the WEP function in the Windows
// 3.1 SDK "Programmers Reference, Volume 2: Functions" before placing
// any additional code in the WEP routine for a Windows 3.0 DLL.
//---------------------------------------------------------------------------
#pragma alloc_text(WEP_TEXT,WEP)

//---------------------------------------------------------------------------
// Performs cleanup tasks when the DLL is unloaded.  WEP() is
// called automatically by Windows when the DLL is unloaded (no
// remaining tasks still have the DLL loaded).    It is strongly
// recommended that a DLL have a WEP() function, even if it does
// nothing but returns success (1), as in this example.
//---------------------------------------------------------------------------
int FAR PASCAL WEP(int fSystemExit)
{
    // Avoid warnings on unused (but required) formal parameters
    fSystemExit = fSystemExit;

    return 1;
}
#endif

//---------------------------------------------------------------------------
// ****>>> Aux fn to subclass only valid windows, and only when we're not
// already subclassing a window.  Takes care of setting up and maintaining
// the two necessary globals.  Returns TRUE if it actually subclassed, FALSE
// otherwise.
//---------------------------------------------------------------------------
BOOL FSubClass(HWND hwnd)
{
    int i;
    HCTL hctlMain;

      if (!IsWindow(hwnd))
        return(FALSE);    // Invalid hwnd parameter

    hctlMain = FindhctlMain(hwnd);
    if(!hctlMain)
        return(FALSE);


      if(i < MAX_MSGBLASTERS)
          if (LpblastDEREF(hctlMain)->lpfnOrigProc)
            return FALSE;    // Already are subclassing

      LpblastDEREF(hctlMain)->lpfnOrigProc =
          (FARPROC)SetWindowLong(hwnd, GWL_WNDPROC, (DWORD)SubClassProc);

    return TRUE;
}


//---------------------------------------------------------------------------
// ****>>> Undo what FSubClass() did.  Takes car of clearing out the two
// necessary globals.
//---------------------------------------------------------------------------
VOID UnSubClass(HWND hWndTarget, HCTL hctlMain)
{
    PMSGBLASTER pMsgBlaster;

    pMsgBlaster = LpblastDEREF(hctlMain);

      // Make sure we're actually subclassing before we undo it.        if (pMsgBlaster->lpfnOrigProc)
    {
        SetWindowLong(hWndTarget, GWL_WNDPROC, (LONG)pMsgBlaster->lpfnOrigProc);
        pMsgBlaster->lpfnOrigProc = 0L;
        pMsgBlaster->hWndTarget = NULL;
    }
}

HCTL FindhctlMain(HWND hWnd)
{
    int j;

    // find the correct hctlMain
      for(j = 0; j < MAX_MSGBLASTERS; j++)
    {
        if(controls[j].hWndTarget == hWnd)
            break;
    }

    return(j == MAX_MSGBLASTERS ? NULL:controls[j].hctlMain);
}


//---------------------------------------------------------------------------
// Create our property popup-window.  Since we want to put up a dialog, this
// window never becomes visible.  Instead, when asked to become visible, it
// will post a message to itself, remining it to put up our dialog.
//
// NOTE: May return NULL!
//---------------------------------------------------------------------------
HWND NEAR HwndInitAboutBox(VOID)
{
    return(CreateWindow(CLASS_ABOUTBOX, NULL, WS_POPUP,
            0, 0, 0, 0, NULL, NULL,
            hmodDLL, NULL));
}

//---------------------------------------------------------------------------
// We asked to show ourself, remain invisible and post a CM_OPENABOUT to
// ourself.  When we receive this message, open the dialog box.
//---------------------------------------------------------------------------
LONG _export FAR PASCAL AboutBoxProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{

    switch (msg)
    {
    case WM_SHOWWINDOW:
        if (wParam)
        {
            PostMessage(hWnd, CM_OPENABOUTBOX, 0, 0L);
            return 0L;
        }
        break;

    case CM_OPENABOUTBOX:
        VBDialogBoxParam(hmodDLL, "AboutBox", (FARPROC)AboutBoxDlgProc, 0L);
        return 0L;
    }

    return DefWindowProc(hWnd, msg, wParam, lParam);
}


//---------------------------------------------------------------------------
// The Dialog Procedure for the AboutBox dialog.
//---------------------------------------------------------------------------
BOOL FAR PASCAL _export AboutBoxDlgProc(HWND hDlg, UINT msg, WPARAM wParam, LPARAM lParam)
{
    switch (msg)
    {
    case WM_INITDIALOG:
    {
        RECT rect;
        int  nx, ny;      // New x and y
        int  width, height;

        // Position dialog so it looks nice:
        GetWindowRect(hDlg, &rect);
        width  = rect.right - rect.left;
        height = rect.bottom - rect.top;
        nx = (GetSystemMetrics(SM_CXSCREEN) - width)  / 2;
        ny = (GetSystemMetrics(SM_CYSCREEN) - height) / 3;
        MoveWindow(hDlg, nx, ny, width, height, FALSE);
        return TRUE;
    }

    case WM_COMMAND:
        if(wParam ==  IDOK)
        {
            EndDialog(hDlg, TRUE);
            return TRUE;
        }
    }
    return FALSE;
}

//-- EOF -------------------------------------------------------------------