MFC messageloop in dialog window - c++

Question

i created a MFC dialog application.
now i want to use a messageloop, but i can not find it. I read that mfc will create it for me but that it will be hidden. so how can i manipulate the messageloop?
i need the messageloop to recieve events from my tray icon which i created for that application.
so that i can use something like that:
long CALLBACK WndProc(HWND hWnd, UINT nMsg, UINT wParam, LONG lParam)
{
switch(nMsg)
{
case (WM_USER + 1):
{
switch(lParam)
{
case WM_RBUTTONUP:
{
/**/
}
}
return 0;
}
default:
return DefWindowProc(hWnd, nMsg, wParam, lParam);
}
}
I'm still a beginner at mfc.

Answer 1

After installing an icon to the system tray by Shell_NotifyIcon, this icon become the extension of your dialog UI. When the user interact with this icon, the UI messages will be re-directed to your dialog by the OS automatically.
To serve these user messages you needs to perform few steps:
(1) Add a message handler definition (ON_MESSAGE(WM_TRAY_NOTIFY, OnTrayNotify)) inside the (.cpp) file. Must be inside the BEGIN_MESSAGE_MAP/END_MESSAGE_MAP block:
BEGIN_MESSAGE_MAP(CTestDlg, CDialog)
//{{AFX_MSG_MAP(CTestDlg)
ON_WM_PAINT()
ON_WM_QUERYDRAGICON()
...
//}}AFX_MSG_MAP
ON_MESSAGE(WM_TRAY_NOTIFY, OnTrayNotify)
END_MESSAGE_MAP()
(2) Add a message handler implementation in the (.cpp) file, to perform the actual work
void CTestDlg::OnTrayNotify(UINT nID, LPARAM lEvent)
{
if (nID==TRAYICON_ID1)
{
// handle messages here
if (lEvent==WM_LBUTTONDBLCLK)
{ // do left button double click, usually restore application
}
if (lEvent==WM_RBUTTONUP)
{ // do right button up, usually popup a menu at clicked location
}
}
}
(3) Add a prototype definition of this message handler (afx_msg void OnTrayNotify(UINT nID, LPARAM lEvent);) inside the (.h) file. Must be inside the BEGIN_MESSAGE_MAP/END_MESSAGE_MAP block:
// Generated message map functions
//{{AFX_MSG(CTestDlg)
virtual BOOL OnInitDialog();
afx_msg void OnPaint();
afx_msg HCURSOR OnQueryDragIcon();
...
//}}AFX_MSG
afx_msg void OnTrayNotify(UINT nID, LPARAM lEvent);
DECLARE_MESSAGE_MAP()
(4) Add definition inside (.h) file
#define WM_TRAY_NOTIFY WM_USER+567
#define TRAYICON_ID1 0x1234
The code above is assuming:
The dialog name is CTestDlg, change it to your dialog name
The user-callback-message identifier (uCallbackMessage) used to setup Shell_NotifyIcon is WM_TRAY_NOTIFY
The identifier of the tray icon (uID) sed to setup Shell_NotifyIcon is TRAYICON_ID1