Shell Hooks and explorer.exe

[RomeoPapacy]

I'm trying to write a replacement shell for Windows at the moment i have a working system tray and (sort-of) working taskbar.

The issue at the moment is the Taskbar is failing to receive window created/activated/destroyed messages when run on it's own.
If I run it on top of explorer it works fine. Even if i kill explorer and run it, it will work fine, but if a log into my user account with cmd.exe as shell and run it from there it receives no messages.

At the moment I'm using SetWindowsHookEx, Does this function rel on some other process to do it's job? or is there and alternative function that will do this job with the need for explorer to have run?

[Banfa]

What happens if you run your program as the shell as opposed to a command prompt?

[RomeoPapacy]

Thank you for your reply:

Same symptoms as when cmd is shell:
- Notification area works wonderfully
- Taskbar only seems to receive HSHELL_LANGUAGE messages

[RomeoPapacy]

If it will help, here is the code for the hook. This is compiled as a DLL using VC++ 2008 Express:
dllmain.cpp:

HINSTANCE hInst;
BOOL APIENTRY DllMain( HMODULE hModule,
                       DWORD  ul_reason_for_call,
                       LPVOID lpReserved
                     )
{
    switch (ul_reason_for_call)
    {
    case DLL_PROCESS_ATTACH:
        hInst = (HINSTANCE) hModule;
        break;
    case DLL_THREAD_ATTACH:
    case DLL_THREAD_DETACH:
    case DLL_PROCESS_DETACH:
        break;
    }
    return TRUE;
}
 

Hook.cpp:

extern HINSTANCE hInst;
HWND callback=0;
HHOOK hHook=0;
std::fstream fLog("C:\\Logs\\Hook.log",std::fstream::out);
HOOK_API void                SetHook(HWND hWnd){
    hHook=SetWindowsHookEx(WH_SHELL,ShellProc,hInst,NULL);
}
LRESULT CALLBACK    ShellProc(int nCode, WPARAM wParam, LPARAM lParam){ 
    if(nCode<0)return CallNextHookEx(hHook,nCode,wParam,lParam);
    HWND h=FindWindow(TEXT("Shell_TrayWnd"),NULL);
    fLog<<"Hook Message:"<<nCode<<endl;
    switch(nCode){
        case HSHELL_WINDOWCREATED:
        case HSHELL_WINDOWACTIVATED:
        case HSHELL_WINDOWDESTROYED:
            PostMessage(h,WM_HOOKPROXY,(WPARAM)nCode,(LPARAM)wParam);
            break;
        case HSHELL_WINDOWREPLACED:
            PostMessage(h,WM_HOOKPROXY,(WPARAM)HSHELL_WINDOWREPLACING,(LPARAM)wParam);
            PostMessage(h,WM_HOOKPROXY,(WPARAM)HSHELL_WINDOWREPLACED,(LPARAM)wParam);
            break;
    }
    return 0L;
}; 

[Banfa]

From the MSDN page on SetWindowsHookEh this paragraph seems relevant

Note that custom shell applications do not receive WH_SHELL messages. Therefore, any application that registers itself as the default shell must call the SystemParametersInfo function before it (or any other application) can receive WH_SHELL messages. This function must be called with SPI_SETMINIMIZEDMETRICS and a MINIMIZEDMETRICS structure. Set the iArrange member of this structure to ARW_HIDE.

I found it by Googling "WH_SHELL"

[RomeoPapacy]

Once again Banfa - you're a lifesaver
I must have read that page at least 5 times and never noticed that.

Thank you.