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1 *------------------------------------- 2 BEEPER1.C -- Timer Demo Program No.1 3 (c) Charles Petzold, 1998 4 -------------------------------------*/ 5 6 #include <Windows.h> 7 8 #define ID_TIMER 1 9 10 LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); 11 12 int WINAPI WinMain( __in HINSTANCE hInstance 13 , __in_opt HINSTANCE hPrevInstance 14 , __in LPSTR lpCmdLine 15 , __in int nShowCmd ) 16 { 17 static TCHAR szAppName[] = TEXT("Bepper1"); 18 HWND hwnd; 19 MSG msg; 20 WNDCLASS wndclass; 21 22 wndclass.style = CS_HREDRAW | CS_VREDRAW; 23 wndclass.lpfnWndProc = WndProc; 24 wndclass.cbClsExtra = 0; 25 wndclass.cbWndExtra = 0; 26 wndclass.hInstance = hInstance; 27 wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION); 28 wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); 29 wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); 30 wndclass.lpszMenuName = NULL; 31 wndclass.lpszClassName = szAppName; 32 33 if (!RegisterClass(&wndclass)) 34 { 35 MessageBox(NULL, TEXT("Program requires Windows NT!") 36 , szAppName, MB_ICONERROR); 37 return 0; 38 } 39 40 hwnd = CreateWindow(szAppName, TEXT("Beeper1 Timer Demo") 41 , WS_OVERLAPPEDWINDOW 42 , CW_USEDEFAULT, CW_USEDEFAULT 43 , CW_USEDEFAULT, CW_USEDEFAULT 44 , NULL, NULL, hInstance, NULL); 45 46 ShowWindow(hwnd, nShowCmd); 47 UpdateWindow(hwnd); 48 49 while (GetMessage(&msg, NULL, 0, 0)) 50 { 51 TranslateMessage(&msg); 52 DispatchMessage(&msg); 53 } 54 55 return msg.wParam; 56 } 57 58 LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) 59 { 60 static BOOL fFlipFlop = FALSE; 61 HBRUSH hBrush; 62 HDC hdc; 63 PAINTSTRUCT ps; 64 RECT rc; 65 66 switch (message) 67 { 68 case WM_CREATE: 69 SetTimer(hwnd, ID_TIMER, 1000, NULL); 70 return 0; 71 72 case WM_TIMER: 73 MessageBeep(-1); 74 fFlipFlop = !fFlipFlop; 75 InvalidateRect(hwnd, NULL, FALSE); 76 return 0; 77 78 case WM_PAINT: 79 hdc = BeginPaint(hwnd, &ps); 80 81 GetClientRect(hwnd, &rc); 82 hBrush = CreateSolidBrush(fFlipFlop ? RGB(255, 0, 0) : RGB(0, 0, 255)); 83 FillRect(hdc, &rc, hBrush); 84 85 EndPaint(hwnd, &ps); 86 DeleteObject(hBrush); 87 return 0; 88 89 case WM_DESTROY: 90 KillTimer(hwnd, ID_TIMER); 91 PostQuitMessage(0); 92 return 0; 93 } 94 95 return DefWindowProc(hwnd, message, wParam, lParam); 96 }