GtkClutter - Clutter.Stage not receiving pointer events

Question

I am using the excellent PyGI AIO (3.14.0) binaries to develop with Gtk3 and Clutter on Windows. So far it has been working great. However, there seems to be a problem with pointer events not reaching the Clutter.Stage inside a GtkClutter.Embed widget. Here is the code:

import sys

from gi.repository import GtkClutter
GtkClutter.init(sys.argv)
from gi.repository import Clutter, Gdk, Gtk, GObject

def main():
    win = Gtk.Window(Gtk.WindowType.TOPLEVEL)

    # Works
    #win.connect('button-press-event', lambda *args: sys.stdout.write("BP\n"))
    #win.connect('button-release-event', lambda *args: sys.stdout.write("BR\n"))
    #win.connect('motion-notify-event', lambda *args: sys.stdout.write("ME\n"))

    embed = GtkClutter.Embed()
    embed.set_size_request(800, 600)

    # Works
    #embed.connect('button-press-event', lambda *args: sys.stdout.write("BP\n"))
    #embed.connect('button-release-event', lambda *args: sys.stdout.write("BR\n"))
    #embed.connect('motion-notify-event', lambda *args: sys.stdout.write("ME\n"))

    stage = embed.get_stage()
    stage.set_reactive(True)
    stage.set_size(800, 600)
    stage.set_color(Clutter.Color.new(0, 128, 0, 255))

    # Fails
    stage.connect('button-press-event', lambda *args: sys.stdout.write("BP\n"))
    stage.connect('button-release-event', lambda *args: sys.stdout.write("BR\n"))
    stage.connect('motion-event', lambda *args: sys.stdout.write("ME\n"))

    # Works (surprisingly...)
    stage.connect('key-press-event', lambda *args: sys.stdout.write("KP\n"))
    stage.connect('key-release-event', lambda *args: sys.stdout.write("KR\n"))

    stage.show_all()

    win.add(embed)

    win.connect("delete-event", Gtk.main_quit)
    win.show_all()

    Gtk.main()

    return 0

if __name__ == '__main__':
    sys.exit(main())

Is the above code correct? I am wondering whether this is a Windows specific issue. Can anybody reproduce the problem on another OS?

Answer 1

I got this kind of report long time ago by a map apps developer. I suggest him to switch to gdk backend a.k.a

from gi.repository import Clutter
Clutter.set_windowing_backend(Clutter.WINDOWING_GDK)

note: above should be done before other clutter stuff

it should catch events now but still all C examples are working fine without that workaround, so I'm clueless about why it doesn't work at binding level. I think your code also already comform gtk-clutter-test.c as well.