DialogBox show nothing

[anrapas]

I've got this slice code inside a DLL:

DWORD processId;
HWND hwndParent;
BOOL CALLBACK enumWindowsProc(HWND hwnd, LPARAM lParam)
{
	DWORD procid;
	GetWindowThreadProcessId(hwnd, &procid);
	if (procid == processId)
	{
		hwndParent = hwnd;
		return FALSE;
	}
	return TRUE;
}

const char* InputBox(LPCSTR title, const char* message, const char* def_value)
{
	HWND hwnd;
	MSG msg;
	processId = GetCurrentProcessId();
	EnumWindows(enumWindowsProc, 0);
	int ret = DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_IB), hwndParent, InputBox_WndProc);

	return "0";
}

Why id doesn't show any Dialog?

Thanks a lot.

[S_M_A]

The best way is to do as they say here http://msdn.microsoft.com/en-us/libr...(v=vs.85).aspx i.e. call GetLastError.

[VictorN]

I've got this slice code inside a DLL:

...
	EnumWindows(enumWindowsProc, 0);
	int ret = DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_IB), hwndParent, InputBox_WndProc);

Why id doesn't show any Dialog?

Why should it show anything?

1. Does IDD_IB template exist?
2. What is hwndParent? Is it a valid handle?
3. What is InputBox_WndProc?

You have to debug your code to be sure all the parameters passed in the DialogBox(...) are valid!
And of course you have to use GetLastError (as S_M_A already mentioned) to obtain the extended error information if some error happened.

[anrapas]

I've found the error.

I use to call the DialogBox function with GetModuleHandle(NULL) instead of DLL HINSTANCE value (provided as first parameter at APIENTRY DllMain function).

Thanks a lot.