Layer shell support

This is almost completely working under Wayland.  To test, use a
compositor that supports Layer Shell, such as KWin.  KWin can be spawned
nested inside an X11 window, such as what Qubes OS provides.

There are two known limitations:

1. The window is too short.
2. The configuration options that control where the app menu appears do
   not work.

.gitlab-ci.yml

@@ -9,7 +9,7 @@ include:
 checks:pylint:
   stage: checks
   before_script:
-    - sudo dnf install -y python3-gobject gtk3 xorg-x11-server-Xvfb python3-mypy
+    - sudo dnf install -y python3-gobject gtk3 xorg-x11-server-Xvfb python3-mypy gtk-layer-shell
     - pip3 install --quiet -r ci/requirements.txt
     - git clone https://github.com/QubesOS/qubes-core-admin-client ~/core-admin-client
   script:
@@ -23,7 +23,7 @@ checks:tests:
   before_script: &before-script
     - "PATH=$PATH:$HOME/.local/bin"
     - sudo dnf install -y python3-gobject gtk3 python3-pytest python3-pytest-asyncio
-      python3-coverage xorg-x11-server-Xvfb python3-inotify sequoia-sqv
+      python3-coverage xorg-x11-server-Xvfb python3-inotify sequoia-sqv gtk-layer-shell
     - pip3 install --quiet -r ci/requirements.txt
     - git clone https://github.com/QubesOS/qubes-core-admin-client ~/core-admin-client
     - git clone https://github.com/QubesOS/qubes-desktop-linux-manager ~/desktop-linux-manager

debian/control

@@ -13,7 +13,8 @@ Build-Depends:
  qubes-desktop-linux-manager,
  python3-gi,
  gobject-introspection,
- gir1.2-gtk-3.0
+ gir1.2-gtk-3.0,
+ gir1.2-gtklayershell-0.1,
 Standards-Version: 3.9.5
 Homepage: https://www.qubes-os.org/
 X-Python3-Version: >= 3.5

qubes_menu/appmenu.py

@@ -27,7 +27,8 @@
 
 import gi
 gi.require_version('Gtk', '3.0')
-from gi.repository import Gtk, Gdk, GLib, Gio
+gi.require_version('GtkLayerShell', '0.1')
+from gi.repository import Gtk, Gdk, GLib, Gio, GtkLayerShell
 
 import gbulb
 gbulb.install()
@@ -208,12 +209,23 @@ def do_activate(self, *args, **kwargs):
             if not self.start_in_background:
                 self.main_window.show_all()
             self.initialize_state()
-            # set size if too big
+            current_width = self.main_window.get_allocated_width()
             current_height = self.main_window.get_allocated_height()
-            max_height = self.main_window.get_screen().get_height() * 0.9
+            # set size if too big
+            max_height = int(self.main_window.get_screen().get_height() * 0.9)
+            assert max_height > 0
             if current_height > max_height:
-                self.main_window.resize(self.main_window.get_allocated_width(),
-                                        int(max_height))
+                self.main_window.resize(current_height, max_height)
+            if GtkLayerShell.is_supported():
+                # The default for layer shell is no keyboard input.
+                # Explicitly request that the compositor use the normal
+                # rules for keyboard input as if this was a normal window.
+                GtkLayerShell.set_keyboard_mode(self.main_window,
+                                        GtkLayerShell.KeyboardMode.ON_DEMAND)
+                # Work around https://github.com/wmww/gtk-layer-shell/issues/167
+                # by explicitly setting the window size.
+                self.main_window.set_size_request(current_width,
+                                                  min(current_height, max_height))
 
             # grab a focus on the initially selected page so that keyboard
             # navigation works
@@ -341,6 +353,14 @@ def perform_setup(self):
                 'domain-feature-delete:' + feature,
                 self._update_settings)
 
+        if GtkLayerShell.is_supported():
+            GtkLayerShell.init_for_window(self.main_window)
+            GtkLayerShell.auto_exclusive_zone_enable(self.main_window)
+            GtkLayerShell.set_anchor(self.main_window, GtkLayerShell.Edge.LEFT,
+                                     True)
+            GtkLayerShell.set_anchor(self.main_window, GtkLayerShell.Edge.TOP,
+                                     True)
+
     def load_style(self, *_args):
         """Load appropriate CSS stylesheet and associated properties."""
         light_ref = (importlib.resources.files('qubes_menu') /

rpm_spec/qubes-desktop-linux-menu.spec.in

@@ -49,6 +49,7 @@ BuildRequires:  gettext
 Requires:  python%{python3_pkgversion}-setuptools
 Requires:  python%{python3_pkgversion}-gbulb
 Requires:  gtk3
+Requires:  gtk-layer-shell
 Requires:  python%{python3_pkgversion}-qubesadmin >= 4.1.8
 Requires:  qubes-artwork >= 4.1.5
 Requires:  qubes-desktop-linux-manager