[gnome-music/wip/jfelder/coremodel-reset-item-changed-signal] coremodel: Correctly disconnect items-changed for player model

[Marinus Schraal <mschraal src gnome org>]

commit 2568f87db60cedbaab96f580ff18f4fd4864479d
Author: Jean Felder <jfelder src gnome org>
Date:   Mon Sep 9 21:23:35 2019 +0200

    coremodel: Correctly disconnect items-changed for player model
    
    When a new player playlist is set, an existing "items-changed" signal
    is disconnected if the new playlist type matches the current playlist
    type. This is wrong because the new model will replace the existing
    one whatever its type is.
    
    Fix the issue by disconnecting an "items-changed" signal as soon as
    the playlist changes.

 gnomemusic/coremodel.py | 38 +++++++++++++++-----------------------
 1 file changed, 15 insertions(+), 23 deletions(-)
---
diff --git a/gnomemusic/coremodel.py b/gnomemusic/coremodel.py
index ef1d67e6..d068257d 100644
--- a/gnomemusic/coremodel.py
+++ b/gnomemusic/coremodel.py
@@ -79,10 +79,9 @@ class CoreModel(GObject.GObject):
         super().__init__()
 
         self._flatten_model = None
-        self._playlist_signal_id = None
+        self._player_signal_id = None
+        self._current_playlist_model = None
         self._previous_playlist_model = None
-        self._search_signal_id = None
-        self._song_signal_id = None
 
         self._model = Gio.ListStore.new(CoreSong)
         self._songliststore = SongListStore(self._model)
@@ -251,6 +250,11 @@ class CoreModel(GObject.GObject):
                 if song.props.state in played_states:
                     song.props.state = SongWidget.State.UNPLAYED
 
+            if self._player_signal_id is not None:
+                self._current_playlist_model.disconnect(self._player_signal_id)
+                self._player_signal_id = None
+                self._current_playlist_model = None
+
             self._playlist_model.remove_all()
 
             if playlist_type == PlayerPlaylist.Type.ALBUM:
@@ -261,7 +265,7 @@ class CoreModel(GObject.GObject):
 
                 self._flatten_model = Gfm.FlattenListModel.new(
                     CoreSong, proxy_model)
-                self._flatten_model.connect("items-changed", _on_items_changed)
+                self._current_playlist_model = self._flatten_model
 
                 for model_song in self._flatten_model:
                     song = CoreSong(
@@ -287,7 +291,7 @@ class CoreModel(GObject.GObject):
 
                 self._flatten_model = Gfm.FlattenListModel.new(
                     CoreSong, proxy_model)
-                self._flatten_model.connect("items-changed", _on_items_changed)
+                self._current_playlist_model = self._flatten_model
 
                 for model_song in self._flatten_model:
                     song = CoreSong(
@@ -305,9 +309,7 @@ class CoreModel(GObject.GObject):
 
                 self.emit("playlist-loaded")
             elif playlist_type == PlayerPlaylist.Type.SONGS:
-                if self._song_signal_id:
-                    self._songliststore.props.model.disconnect(
-                        self._song_signal_id)
+                self._current_playlist_model = self._songliststore.props.model
 
                 for song in self._songliststore.props.model:
                     self._playlist_model.append(song)
@@ -315,26 +317,16 @@ class CoreModel(GObject.GObject):
                     if song.props.state == SongWidget.State.PLAYING:
                         song.props.state = SongWidget.State.PLAYED
 
-                self._song_signal_id = self._songliststore.props.model.connect(
-                    "items-changed", _on_items_changed)
-
                 self.emit("playlist-loaded")
             elif playlist_type == PlayerPlaylist.Type.SEARCH_RESULT:
-                if self._search_signal_id:
-                    self._song_search_flatten.disconnect(
-                        self._search_signal_id)
+                self._current_playlist_model = self._song_search_flatten
 
                 for song in self._song_search_flatten:
                     self._playlist_model.append(song)
 
-                self._search_signal_id = self._song_search_flatten.connect(
-                    "items-changed", _on_items_changed)
-
                 self.emit("playlist-loaded")
             elif playlist_type == PlayerPlaylist.Type.PLAYLIST:
-                if self._playlist_signal_id:
-                    self._previous_playlist_model.disconnect(
-                        self._playlist_signal_id)
+                self._current_playlist_model = model
 
                 for model_song in model:
                     song = CoreSong(
@@ -351,11 +343,11 @@ class CoreModel(GObject.GObject):
                         GObject.BindingFlags.BIDIRECTIONAL
                         | GObject.BindingFlags.SYNC_CREATE)
 
-                self._playlist_signal_id = model.connect(
-                    "items-changed", _on_items_changed)
-
                 self.emit("playlist-loaded")
 
+        if self._current_playlist_model is not None:
+            self._player_signal_id = self._current_playlist_model.connect(
+                "items-changed", _on_items_changed)
         self._previous_playlist_model = model
 
     def stage_playlist_deletion(self, playlist):