[gnome-music/wip/mschraal/grltracker-batch-initial-fill: 3/3] grltrackerwrapper: Batch listmodel updates

[Marinus Schraal <mschraal src gnome org>]

commit 0ba494b483a67e6c4f807cc7af46d207829537aa
Author: Marinus Schraal <mschraal gnome org>
Date:   Mon Nov 4 14:13:53 2019 +0100

    grltrackerwrapper: Batch listmodel updates
    
    Grilo provides Music query results one at a time, this results in a lot
    of signal traffic adding songs, albums and artists to the different
    listmodels.
    
    This patch adds batch update functionality to the initial fill queries,
    reducing the amount of signals and improve loading times.

 gnomemusic/grilowrappers/grltrackerwrapper.py | 27 ++++++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)
---
diff --git a/gnomemusic/grilowrappers/grltrackerwrapper.py b/gnomemusic/grilowrappers/grltrackerwrapper.py
index ceb8242e..ecda4968 100644
--- a/gnomemusic/grilowrappers/grltrackerwrapper.py
+++ b/gnomemusic/grilowrappers/grltrackerwrapper.py
@@ -38,6 +38,8 @@ class GrlTrackerWrapper(GObject.GObject):
     """Wrapper for the Grilo Tracker source.
     """
 
+    _SPLICE_SIZE = 100
+
     METADATA_KEYS = [
         Grl.METADATA_KEY_ALBUM,
         Grl.METADATA_KEY_ALBUM_ARTIST,
@@ -341,6 +343,7 @@ class GrlTrackerWrapper(GObject.GObject):
 
     def _initial_songs_fill(self, source):
         self._window.notifications_popup.push_loading()
+        songs_added = []
 
         def _add_to_model(source, op_id, media, user_data, error):
             if error:
@@ -349,12 +352,16 @@ class GrlTrackerWrapper(GObject.GObject):
                 return
 
             if not media:
+                self._model.splice(self._model.get_n_items(), 0, songs_added)
                 self._window.notifications_popup.pop_loading()
                 return
 
             song = CoreSong(media, self._coreselection, self._grilo)
-            self._model.append(song)
+            songs_added.append(song)
             self._hash[media.get_id()] = song
+            if len(songs_added) == self._SPLICE_SIZE:
+                self._model.splice(self._model.get_n_items(), 0, songs_added)
+                songs_added.clear()
 
         query = """
         SELECT
@@ -390,6 +397,7 @@ class GrlTrackerWrapper(GObject.GObject):
 
     def _initial_albums_fill(self, source):
         self._window.notifications_popup.push_loading()
+        albums_added = []
 
         def _add_to_albums_model(source, op_id, media, user_data, error):
             if error:
@@ -398,12 +406,18 @@ class GrlTrackerWrapper(GObject.GObject):
                 return
 
             if not media:
+                self._albums_model.splice(
+                    self._albums_model.get_n_items(), 0, albums_added)
                 self._window.notifications_popup.pop_loading()
                 return
 
             album = CoreAlbum(media, self._coremodel)
-            self._albums_model.append(album)
             self._album_ids[media.get_id()] = album
+            albums_added.append(album)
+            if len(albums_added) == self._SPLICE_SIZE:
+                self._albums_model.splice(
+                    self._albums_model.get_n_items(), 0, albums_added)
+                albums_added.clear()
 
         query = """
         SELECT
@@ -437,6 +451,7 @@ class GrlTrackerWrapper(GObject.GObject):
 
     def _initial_artists_fill(self, source):
         self._window.notifications_popup.push_loading()
+        artists_added = []
 
         def _add_to_artists_model(source, op_id, media, user_data, error):
             if error:
@@ -445,13 +460,19 @@ class GrlTrackerWrapper(GObject.GObject):
                 return
 
             if not media:
+                self._artists_model.splice(
+                    self._artists_model.get_n_items(), 0, artists_added)
                 self._coremodel.emit("artists-loaded")
                 self._window.notifications_popup.pop_loading()
                 return
 
             artist = CoreArtist(media, self._coremodel)
-            self._artists_model.append(artist)
             self._artist_ids[media.get_id()] = artist
+            artists_added.append(artist)
+            if len(artists_added) == self._SPLICE_SIZE:
+                self._artists_model.splice(
+                    self._artists_model.get_n_items(), 0, artists_added)
+                artists_added.clear()
 
         query = """
         SELECT