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/ Windows 95 API Bible / Windows 95 API Bible 3 Disc Set.iso / Win32 API Bible Book 3 of 3 / CHAPTE18 / YIELD.C < prev    next >
C/C++ Source or Header  |  1996-04-29  |  10KB  |  300 lines
  1.  
  2. #include <windows.h>
  3. #include <stdio.h>
  4. #include "Yield.h"
  5.  
  6. #if defined (WIN32)
  7.     #define IS_WIN32 TRUE
  8. #else
  9.     #define IS_WIN32 FALSE
  10. #endif
  11.  
  12. #define IS_NT      IS_WIN32 && (BOOL)(GetVersion() < 0x80000000)
  13. #define IS_WIN32S  IS_WIN32 && (BOOL)(!(IS_NT) && (LOBYTE(LOWORD(GetVersion()))<4))
  14. #define IS_WIN95   (BOOL)(!(IS_NT) && !(IS_WIN32S)) && IS_WIN32
  15.  
  16. HINSTANCE hInst;   // current instance
  17.  
  18. LPCTSTR lpszAppName = "MyApp";
  19. LPCTSTR lpszTitle   = "mciSetYieldProc()"; 
  20.  
  21.  
  22. BOOL RegisterWin95( CONST WNDCLASS* lpwc );
  23.  
  24.  
  25. int APIENTRY WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance,
  26.                       LPTSTR lpCmdLine, int nCmdShow)
  27. {
  28.    MSG      msg;
  29.    HWND     hWnd; 
  30.    WNDCLASS wc;
  31.  
  32.    wc.style         = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
  33.    wc.lpfnWndProc   = (WNDPROC)WndProc;       
  34.    wc.cbClsExtra    = 0;                      
  35.    wc.cbWndExtra    = 0;                      
  36.    wc.hInstance     = hInstance;              
  37.    wc.hIcon         = LoadIcon (hInstance, lpszAppName); 
  38.    wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
  39.    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
  40.    wc.lpszMenuName  = lpszAppName;              
  41.    wc.lpszClassName = lpszAppName;              
  42.  
  43.    if ( IS_WIN95 )
  44.    {
  45.       if ( !RegisterWin95( &wc ) )
  46.          return( FALSE );
  47.    }
  48.    else if ( !RegisterClass( &wc ) )
  49.       return( FALSE );
  50.  
  51.    hInst = hInstance; 
  52.  
  53.    hWnd = CreateWindow( lpszAppName, 
  54.                         lpszTitle,    
  55.                         WS_OVERLAPPEDWINDOW, 
  56.                         CW_USEDEFAULT, 0, 
  57.                         CW_USEDEFAULT, 0,  
  58.                         NULL,              
  59.                         NULL,              
  60.                         hInstance,         
  61.                         NULL               
  62.                       );
  63.  
  64.    if ( !hWnd ) 
  65.       return( FALSE );
  66.  
  67.    ShowWindow( hWnd, nCmdShow ); 
  68.    UpdateWindow( hWnd );         
  69.  
  70.    while( GetMessage( &msg, NULL, 0, 0) )   
  71.    {
  72.       TranslateMessage( &msg ); 
  73.       DispatchMessage( &msg );  
  74.    }
  75.  
  76.    return( msg.wParam ); 
  77. }
  78.  
  79.  
  80. BOOL RegisterWin95( CONST WNDCLASS* lpwc )
  81. {
  82.     WNDCLASSEX wcex;
  83.  
  84.    wcex.style         = lpwc->style;
  85.    wcex.lpfnWndProc   = lpwc->lpfnWndProc;
  86.    wcex.cbClsExtra    = lpwc->cbClsExtra;
  87.    wcex.cbWndExtra    = lpwc->cbWndExtra;
  88.    wcex.hInstance     = lpwc->hInstance;
  89.    wcex.hIcon         = lpwc->hIcon;
  90.    wcex.hCursor       = lpwc->hCursor;
  91.    wcex.hbrBackground = lpwc->hbrBackground;
  92.    wcex.lpszMenuName  = lpwc->lpszMenuName;
  93.    wcex.lpszClassName = lpwc->lpszClassName;
  94.  
  95.    // Added elements for Windows 95.
  96.    //...............................
  97.    wcex.cbSize = sizeof(WNDCLASSEX);
  98.    wcex.hIconSm = LoadImage(wcex.hInstance, lpwc->lpszClassName, 
  99.                             IMAGE_ICON, 16, 16,
  100.                             LR_DEFAULTCOLOR );
  101.             
  102.    return RegisterClassEx( &wcex );
  103. }
  104.  
  105. #define MSG_LEN          1024
  106.  
  107.  
  108. char             msg[MSG_LEN+1];
  109. HWND             hListBox = NULL;
  110. MCIERROR         rc;
  111. MCIDEVICEID      uDeviceId = 0;
  112. MCI_OPEN_PARMS   open;
  113. MCI_PLAY_PARMS   play;
  114. UINT             uTimer;
  115. UINT             nYieldProcCalled;
  116.  
  117. int CALLBACK MyYieldProc(MCIDEVICEID uDeviceId, DWORD dwData);
  118.  
  119.  
  120. LRESULT CALLBACK WndProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam )
  121. {
  122.    BOOL      brc;   // tmp
  123.    YIELDPROC yp = NULL;
  124.  
  125.    switch( uMsg )
  126.    {
  127.       case WM_CREATE :
  128.               // Create ListBox
  129.               //...............
  130.  
  131.               hListBox = CreateWindow( "LISTBOX", "",    
  132.                                        WS_CHILD | LBS_NOTIFY | 
  133.                                        WS_VSCROLL | WS_BORDER | 
  134.                                        WS_VISIBLE | LBS_NOINTEGRALHEIGHT, 
  135.                                        0, 0, 
  136.                                        0, 0,  
  137.                                        hWnd,              
  138.                                        (HMENU)101,              
  139.                                        hInst,         
  140.                                        NULL );
  141.               break;
  142.  
  143.       case WM_SIZE :
  144.               MoveWindow( hListBox, 0, 0, 
  145.                           LOWORD( lParam ), 
  146.                           HIWORD( lParam ), TRUE );
  147.               break;
  148.  
  149.       case WM_COMMAND :
  150.               switch( LOWORD( wParam ) )
  151.               {
  152.                  case IDM_TEST:
  153.                         {
  154.                            SendMessage(hListBox, LB_RESETCONTENT, 0, 0);
  155.  
  156.                            // open device
  157.                            //............
  158.  
  159.                            open.dwCallback       = (DWORD)hWnd;
  160.                            open.lpstrDeviceType  = "waveaudio";
  161.                            open.lpstrElementName = "sample2.wav";
  162.                            open.lpstrAlias       = "song";
  163.  
  164.                            rc = mciSendCommand(0, MCI_OPEN, 
  165.                                                MCI_OPEN_TYPE    | 
  166.                                                MCI_OPEN_ELEMENT |
  167.                                                MCI_OPEN_ALIAS,
  168.                                                (DWORD)&open);
  169.  
  170.                            if (rc)
  171.                            {
  172.                                mciGetErrorString(rc, msg, MSG_LEN);
  173.                                MessageBox(hWnd, msg, NULL, MB_ICONSTOP|MB_OK);
  174.                                mciSendCommand(MCI_ALL_DEVICE_ID, MCI_CLOSE, 
  175.                                               MCI_WAIT, (DWORD)NULL);
  176.                                return(0);
  177.                            }
  178.  
  179.                            // setup stuff
  180.                            //............
  181.  
  182.                            uDeviceId = open.wDeviceID;
  183.  
  184.                            if ( uDeviceId != mciGetDeviceID("song") )
  185.                            {
  186.                                sprintf(msg, "Device Id mis-match %ld != %ld",
  187.                                        uDeviceId, mciGetDeviceID("song") );
  188.                                MessageBox(hWnd, msg, NULL, MB_ICONSTOP|MB_OK);
  189.                                mciSendCommand(MCI_ALL_DEVICE_ID, MCI_CLOSE, 
  190.                                               MCI_WAIT, (DWORD)NULL);
  191.                                return(0);
  192.                            }
  193.  
  194.                            play.dwCallback   = (DWORD)hWnd;
  195.                            nYieldProcCalled  = 0;
  196.  
  197.                            // display Creator Task
  198.                            //.....................
  199.  
  200.                            sprintf(msg, "Creater task handle = %d",
  201.                                         mciGetCreatorTask(uDeviceId) );
  202.                            SendMessage(hListBox, LB_ADDSTRING, 0, (LPARAM)msg);
  203.  
  204.                            // set yield proc address
  205.                            //.......................
  206.                            yp = mciGetYieldProc(uDeviceId, NULL);
  207.  
  208.                            brc = mciSetYieldProc(uDeviceId, MyYieldProc, (DWORD)NULL);
  209.                            uTimer = SetTimer(hWnd, 1, 20, NULL);
  210.  
  211.                            // playback
  212.                            //.........
  213.                            rc = mciSendCommand(uDeviceId, 
  214.                                                MCI_PLAY, 
  215.                                                MCI_WAIT, 
  216.                                                (DWORD)&play);
  217.  
  218.                            mciSendCommand(uDeviceId, MCI_CLOSE, 0, (DWORD)NULL);
  219.                            KillTimer(hWnd, uTimer);
  220.  
  221.                            sprintf(msg, "MyYieldProc() function called %ld times", 
  222.                                    nYieldProcCalled);
  223.                            SendMessage(hListBox, LB_ADDSTRING, 0, (LPARAM)msg);
  224.  
  225.                            // Restore old yield proc.
  226.                            //........................
  227.                            mciSetYieldProc(uDeviceId, yp, (DWORD)NULL);
  228.                         }
  229.                         break;
  230.  
  231.                  case IDM_ABOUT :
  232.                         DialogBox( hInst, "AboutBox", hWnd, About );
  233.                         break;
  234.  
  235.                  case IDM_EXIT :
  236.                         DestroyWindow(hWnd);
  237.                         break;
  238.               }
  239.               break;
  240.  
  241.       case MM_MCINOTIFY:
  242.               // close waveform-audio device
  243.               //............................
  244.               mciSendCommand(uDeviceId, MCI_CLOSE, 0, (DWORD)NULL);
  245.               break;
  246.  
  247.       case WM_DESTROY :
  248.               PostQuitMessage(0);
  249.               break;
  250.  
  251.       default :
  252.             return( DefWindowProc( hWnd, uMsg, wParam, lParam ) );
  253.    }
  254.  
  255.    return( 0L );               
  256. }
  257.  
  258.  
  259. int CALLBACK MyYieldProc(MCIDEVICEID uDeviceId, DWORD dwData)
  260. {
  261.    nYieldProcCalled++;
  262.    
  263.    return(0);
  264. }
  265.  
  266.  
  267. LRESULT CALLBACK About( HWND hDlg,           
  268.                         UINT message,        
  269.                         WPARAM wParam,       
  270.                         LPARAM lParam)
  271. {
  272.    switch (message) 
  273.    {
  274.        case WM_INITDIALOG: 
  275.                return (TRUE);
  276.  
  277.        case WM_COMMAND:                              
  278.                if (   LOWORD(wParam) == IDOK         
  279.                    || LOWORD(wParam) == IDCANCEL)    
  280.                {
  281.                        EndDialog(hDlg, TRUE);        
  282.                        return (TRUE);
  283.                }
  284.                break;
  285.    }
  286.  
  287.    return (FALSE); 
  288. }
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