Shell_NotifyIcon uses IUserNotification under the hood. I played around with it and made a utility out of it. I heard of a visually impaired sysadmin who uses it to make his scripts screen reader compatible. It is command line, it does not have a message loop.
It is self aware, meaning that notifications sent to it will be queued (you have control over it). For that to work, I provided a IQueryContinue implementation. The project is in C++ and is open source, help yourself.
Here is the guts of it :
HRESULT NotifyUser(const NOTIFU_PARAM& params, IQueryContinue *querycontinue, IUserNotificationCallback *notifcallback)
{
HRESULT result = E_FAIL;
IUserNotification *un = 0;
IUserNotification2 *deux = 0; //French pun : "un" above stands for UserNotification but it also means 1 in French. deux means 2.
//First try with the Vista/Windows 7 interface
//(unless /xp flag is specified
if (!params.mForceXP)
result = CoCreateInstance(CLSID_UserNotification, 0, CLSCTX_ALL, IID_IUserNotification2, (void**)&deux);
//Fall back to Windows XP
if (!SUCCEEDED(result))
{
TRACE(eWARN, L"Using Windows XP interface IUserNotification\n");
result = CoCreateInstance(CLSID_UserNotification, 0, CLSCTX_ALL, IID_IUserNotification, (void**)&un);
}
else
{
TRACE(eINFO, L"Using Vista interface IUserNotification2\n");
un = (IUserNotification*)deux; //Rather ugly cast saves some code...
}
if (SUCCEEDED(result))
{
const std::basic_string<TCHAR> crlf_text(L"\\n");
const std::basic_string<TCHAR> crlf(L"\n");
std::basic_string<TCHAR> text(params.mText);
size_t look = 0;
size_t found;
//Replace \n with actual CRLF pair
while ((found = text.find(crlf_text, look)) != std::string::npos)
{
text.replace(found, crlf_text.size(), crlf);
look = found+1;
}
result = un->SetIconInfo(params.mIcon, params.mTitle.c_str());
result = un->SetBalloonInfo(params.mTitle.c_str(), text.c_str(), params.mType);
//Looks like it controls what happends when the X button is
//clicked on
result = un->SetBalloonRetry(0, 250, 0);
if (deux)
result = deux->Show(querycontinue, 250, notifcallback);
else
result = un->Show(querycontinue, 250);
un->Release();
}
return result;
}
MessageBox()
, in which once could get away with having no owner window. The reason is that my tiny application is designed to run in multiple instances without each knowing about the other. So, I don't have the "luxury" of a central managing app with a single icon. Since the number of those instances can reach hundreds (or thousands) I don't want to each add an icon... I wish popping up a balloon were as simple as aMessageBox()
.