I'm new to GDI-Programming in C++ and I want to grap the device context respectively the bitmap of the device context every time the engines has changed it (just think of an online printing application). My first approach was to get the device context of main window, but then I realized that I need the device context of every tab (=of every gecko instance), also of the hidden ones.
First I started to grap the current active tab in this way:
HWND h = m_pBrowserFrameGlue->GetBrowserFrameNativeWnd(); // whole window
CBrowserFrame* frame = (CBrowserFrame*)CWnd::FromHandle(h); // browser frame
CBrowserView* view = (CBrowserView*)frame->GetActiveView(); // current tab
// get device context of current tab
HDC hDC = CreateCompatibleDC(*(view->GetDC()));
But this device context seems to be invalid. Could anybody tell me how to get the device context of the BrowserView? Or is there any gecko interface to get the internal engine's dc?