Question

According to everything I’ve seen, the following C++ program should be displaying a balloon tool tip from the tray icon when I left-click in the application window, yet it’s not working. Can anyone tell me what I’m missing?

This is on XP with version 6.0 of Shell32.dll (verified with DllGetVersion).

Thanks!

    #include 'stdafx.h'     #include 'shellapi.h'      LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);      int APIENTRY _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow)     {         MSG msg;          WNDCLASS wc;         memset(&wc, 0, sizeof(wc));         wc.lpfnWndProc = WndProc;         wc.hInstance = hInstance;         wc.hCursor = LoadCursor(NULL, IDC_ARROW);         wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);         wc.lpszClassName = 'sysTrayTest';         RegisterClass(&wc);          HWND hWnd = CreateWindow('sysTrayTest', '',                                  WS_OVERLAPPEDWINDOW,                                 CW_USEDEFAULT, 0, 500, 500,                                  NULL, NULL, hInstance, NULL);         if (hWnd)         {             ShowWindow(hWnd, nCmdShow);             while (GetMessage(&msg, NULL, 0, 0))             {                 TranslateMessage(&msg);                 DispatchMessage(&msg);             }         }          return 0;     }      LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)     {         switch (message)         {             case WM_DESTROY:             {                 NOTIFYICONDATA nid;                 memset(&nid, 0, sizeof(NOTIFYICONDATA));                 nid.cbSize = sizeof(NOTIFYICONDATA);                 nid.hWnd = hWnd;                 nid.uID = 1;                 Shell_NotifyIcon(NIM_DELETE, &nid);                  PostQuitMessage(0);             }             break;              case WM_CREATE:             {                 NOTIFYICONDATA nid;                 memset(&nid, 0, sizeof(NOTIFYICONDATA));                 nid.cbSize = sizeof(NOTIFYICONDATA);                 nid.hWnd = hWnd;                 nid.uID = 1;                 nid.uFlags = NIF_ICON | NIF_MESSAGE | NIF_TIP;                 nid.uCallbackMessage = WM_USER + 200;                 nid.hIcon = LoadIcon(NULL, IDI_INFORMATION);                 lstrcpy (nid.szTip, 'Test Tip');                 Shell_NotifyIcon(NIM_ADD, &nid);             }             break;              case WM_LBUTTONDOWN:             {                 NOTIFYICONDATA nid;                 memset(&nid, 0, sizeof(NOTIFYICONDATA));                 nid.cbSize = sizeof(NOTIFYICONDATA);                 nid.hWnd = hWnd;                 nid.uID = 1;                 nid.uFlags = NIF_INFO;                 lstrcpy(nid.szInfo, 'Test balloon tip');                 lstrcpy(nid.szInfoTitle, 'Test Title');                 nid.dwInfoFlags = NIIF_INFO;                 nid.uTimeout = 15000;                 Shell_NotifyIcon(NIM_MODIFY, &nid);             }             break;              default:                 return DefWindowProc(hWnd, message, wParam, lParam);         }         return 0;     } 

Answer 1

Bah, I figured it out. For some reason with the headers I have…

sizeof(NOTIFYICONDATA) == 508

whereas…

NOTIFYICONDATA_V3_SIZE == 504
NOTIFYICONDATA_V2_SIZE == 488
NOTIFYICONDATA_V1_SIZE == 88

If I specify either V2 or V3 instead of sizeof(NOTIFYICONDATA) the balloon tips show up just fine.