I am trying Mx toolkit demo code on this page but I get following error:
$ valac --pkg mx-1.0 mxgui.vala
mxgui.vala:4.7-4.8: error: The namespace name `Mx' could not be found
using Mx;
^^
Compilation failed: 1 error(s), 0 warning(s)
I have following clutter packages installed on my Debian Stable Linux system:
$ apt search clutter | grep installed
gir1.2-clutter-1.0/stable,now 1.26.4+dfsg-2 amd64 [installed]
gir1.2-cogl-1.0/stable,now 1.22.8-2 amd64 [installed,automatic]
gir1.2-coglpango-1.0/stable,now 1.22.8-2 amd64 [installed,automatic]
gir1.2-gtkclutter-1.0/stable,now 1.8.4-4 amd64 [installed]
libclutter-1.0-0/stable,now 1.26.4+dfsg-2 amd64 [installed]
libclutter-1.0-common/stable,stable,now 1.26.4+dfsg-2 all [installed,automatic]
libclutter-1.0-dev/stable,now 1.26.4+dfsg-2 amd64 [installed]
libclutter-gtk-1.0-0/stable,now 1.8.4-4 amd64 [installed]
libclutter-gtk-1.0-dev/stable,now 1.8.4-4 amd64 [installed]
libxkbcommon-dev/stable,now 1.0.3-2 amd64 [installed,automatic]
libxkbcommon0/stable,now 1.0.3-2 amd64 [installed,automatic]
Where is the problem and how can it be solved?
Mx is not developed any more, and Clutter has been archived in early 2022 after being in deep maintenance mode since 2016.
You should not use Mx or Clutter in newly written code. The recommendation is to use GTK4.