I have 1 Picture Control and want to make it not screen record-able.
In .Net, I have been using SetWindowDisplayAffinity
:
WDA_MONTOR = 1;
SetWindowDisplayAffinity(this.Handle, WDA_MONTOR);
Now I have moved to MFC for native performance.
I am using this following code which don't prevent screenshots:
HWND Handle = this->GetDlgItem(IDC_SCREEN)->m_hWnd;
SetWindowDisplayAffinity(Handle, WDA_MONITOR);
Complete example:
if(SetWindowDisplayAffinity(hWnd, WDA_MONITOR)==false)
{
wchar_t buf[256];
FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
buf, (sizeof(buf) / sizeof(wchar_t)), NULL);
AfxMessageBox(buf);
}
GetLastError
says "parameter is incorrect".
According to Raymond chen:
The .NET version was passing the form's window handle (a top-level window), but your MFC version is passing a control's window handle (a child window). Use the top-level window.
That's mean I would have to use Form handle instead of PictureBox handle. So change
HWND Handle = this->GetDlgItem(IDC_SCREEN)->m_hWnd; //PictureBox handle
SetWindowDisplayAffinity(Handle, WDA_MONITOR);
to
HWND Handle = this->m_hWnd; //form handle
SetWindowDisplayAffinity(Handle, WDA_MONITOR);
Reason: Form window is parent and top-level window.