rind: Check notifications from the main thread

Gtk really doesn't like notifications coming from other threads, so we
need to handle notifications from the main thread through an idle task.

Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>

rind/gtk.py

@@ -1,7 +1,8 @@
 # Copyright 2019 (c) Anna Schumaker.
+import curds
 import gi
 gi.require_version("Gtk", "3.0")
-from gi.repository import Gtk
+from gi.repository import Gtk, GLib
 
 Builder = Gtk.Builder()
 Builder.add_from_file("emmental.ui")
@@ -9,7 +10,8 @@ Builder.add_from_file("emmental.ui")
 class EmmentalApplication(Gtk.Application):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, application_id="org.gtk.emmental", **kwargs)
-        self.window = None
+        self.window  = None
+        self.idle_id = None
 
     def do_activate(self):
         if self.window == None:
@@ -17,4 +19,16 @@ class EmmentalApplication(Gtk.Application):
             self.add_window(self.window)
         self.window.present()
 
+    def do_shutdown(self):
+        Gtk.Application.do_shutdown(self)
+        GLib.source_remove(self.idle_id)
+
+    def do_startup(self):
+        Gtk.Application.do_startup(self)
+        self.idle_id = GLib.idle_add(self.on_idle)
+
+    def on_idle(self):
+        curds.Notify.run_queued()
+        return GLib.SOURCE_CONTINUE
+
 Application  = EmmentalApplication()

rind/manager.py

@@ -2,7 +2,6 @@
 from . import gtk
 from . import playlist
 import curds
-import threading
 from gi.repository import GObject, Gtk, GLib
 
 toplevel = [ "Collection", "Previous", None, "Library" ]
@@ -10,11 +9,8 @@ toplevel = [ "Collection", "Previous", None, "Library" ]
 class ManagerModel(GObject.GObject, Gtk.TreeModel):
     def __init__(self, *args, **kwargs):
         GObject.GObject.__init__(self)
-        curds.Notify.notify_me("add-track", self.on_add_track)
-        curds.Notify.notify_me("new-library-playlist", self.on_new_library)
-
-        self.update_lock  = threading.Lock()
-        self.update_queue = [ ]
+        curds.Notify.notify_me("add-track", self.on_add_track, queue=True)
+        curds.Notify.notify_me("new-library-playlist", self.on_new_library, queue=True)
 
     def can_select_path(self, selection, model, path, current):
         plist = self.iter_playlist(self.get_iter(path))
@@ -105,17 +101,9 @@ class ManagerModel(GObject.GObject, Gtk.TreeModel):
         return None
 
     def on_add_track(self, plist, track):
-        with self.update_lock:
-            if not plist in self.update_queue:
-                self.update_queue.append(plist)
-                GLib.idle_add(self.on_idle, priority=GLib.PRIORITY_DEFAULT)
-
-    def on_idle(self, *args):
-        with self.update_lock:
-            plist = self.update_queue.pop(0)
-            iter  = self.find_playlist(plist)
+        iter  = self.find_playlist(plist)
+        if iter:
             self.row_changed(self.get_path(iter), iter)
-        return GLib.SOURCE_REMOVE
 
     def on_new_library(self, plist):
         iter = self.find_playlist(plist)

rind/playlist.py

@@ -10,7 +10,7 @@ class PlaylistModel(GObject.GObject, Gtk.TreeModel):
     def __init__(self, *args, **kwargs):
         GObject.GObject.__init__(self)
         self.playlist = curds.PlaylistManager["Collection"]
-        curds.Notify.notify_me("add-track", self.on_add_track)
+        curds.Notify.notify_me("add-track", self.on_add_track, queue=True)
         RandomButton.connect("toggled", self.on_random_toggled)
 
     def do_get_column_type(self, col):

rind/test_gtk.py

@@ -20,6 +20,7 @@ class TestGtk(unittest.TestCase):
         while gtk.Application.window == None:
             time.sleep(0.1)
         self.assertTrue(window.is_visible())
+        self.assertGreater(gtk.Application.idle_id, 0)
         gtk.Application.quit()
         thread.stop()