scrolling over the tray icon switches among devices; fixes #101

It now works for the standard systray as well, not just the
appindicator.

lib/solaar/ui/tray.py

@@ -67,15 +67,14 @@ def _create_menu(quit_handler):
 	return menu
 
 
-try:
-	# raise ImportError
-	from gi.repository import AppIndicator3
-
-	if _log.isEnabledFor(_DEBUG):
-		_log.debug("using AppIndicator3")
-
 _last_scroll = 0
-	def _scroll(ind, _ignore, direction):
+def _scroll(tray_icon, event, direction=None):
+	if direction is None:
+		direction = event.direction
+		now = event.time / 1000.0
+	else:
+		now = None
+
 	if direction != ScrollDirection.UP and direction != ScrollDirection.DOWN:
 		# ignore all other directions
 		return
@@ -88,7 +87,7 @@ try:
 	# scroll events come way too fast (at least 5-6 at once)
 	# so take a little break between them
 	global _last_scroll
-		now = _timestamp()
+	now = now or _timestamp()
 	if now - _last_scroll < 0.33:  # seconds
 		return
 	_last_scroll = now
@@ -144,6 +143,13 @@ try:
 	_update_tray_icon()
 
 
+try:
+	# raise ImportError
+	from gi.repository import AppIndicator3
+
+	if _log.isEnabledFor(_DEBUG):
+		_log.debug("using AppIndicator3")
+
 	def _create(menu):
 		theme_paths = Gtk.IconTheme.get_default().get_search_path()
 
@@ -210,10 +216,9 @@ except ImportError:
 		icon.set_title(NAME)
 		icon.set_tooltip_text(NAME)
 		icon.connect('activate', _window_toggle)
-
+		icon.connect('scroll-event', _scroll)
-		icon.connect('popup_menu',
+		icon.connect('popup-menu',
-						lambda icon, button, time:
+						lambda icon, button, time: menu.popup(None, None, icon.position_menu, icon, button, time))
-							menu.popup(None, None, icon.position_menu, icon, button, time))
 
 		return icon