放大 Linux：简单 X11 windows 无法共享

Question

I'm using the Zoom video conference system on Ubuntu 20.04 with Gnome and X11 (not Wayland).

I wrote an application which directly uses X11 instructions ( XCreateSimpleWindow() ) to open a window. This window cannot be shared on Zoom; it simply doesn't appear on the list of windows that can selected for sharing (my terminals, editors, web browsers appear in the list). It can be shared with "Share Screen Portion", though.

Does anyone know what qualities a window must have such that it can be shared in Zoom? Does my code have to register the window with some Linux / Gnome instance? Are there any requirements for event handling in my application?

Thanks a lot for your help!

Answer 1

I think, I found a solution. Apparently, Zoom only considers a window for sharing if the X11 property _NET_WM_NAME is set. Here's how I do it from C++ (plain X11 code):

  // set _NET_WM_NAME: without this, the window is not visible for Zoom screen sharing
  // from https://gist.github.com/mattn/105615
  Atom net_wm_name_atom = XInternAtom(dsp, "_NET_WM_NAME", 0);
  Atom utf8_string_atom = XInternAtom(dsp, "UTF8_STRING", 0);
  const char *net_wm_name = "something";
  XChangeProperty(dsp, win, net_wm_name_atom, utf8_string_atom, 8, PropModeReplace,
          (unsigned char*) net_wm_name, strlen(net_wm_name));
  
  // map window to screen
  XMapWindow(dsp, win);

Now the window is no longer invisible for Zoom which means it appears in the list of windows which can be selected for screen sharing.