[gnome-music/wip/jfelder/albumsview-selection-mode-launch: 2/2] artistsview: Correctly select the first artist on launch

[Jean Felder <jfelder src gnome org>]

commit 66458b41b1718919cd0fc7fea885776ac1bd8e8c
Author: Jean Felder <jfelder src gnome org>
Date:   Tue Mar 24 16:32:11 2020 +0100

    artistsview: Correctly select the first artist on launch
    
    On some setups (mostly flatpak), the first artist from the
    ArtistsView's sidebar may not be selected on launch.
    Indeed, it relies on listening to the artists-loaded signal from the
    CoreModel to select the first artist once the artists model is
    loaded. However, this signal may already have been emitted when the
    ArtistView is built. In that case, the first artist will never be
    selected.
    
    Fix the issue by changing artists-loaded signal to a property. This
    allows to check if the artist model is already loaded:
    - if the artists are available, the first first artist can be selected
    - if the artists are not available, listen to artists_available change
    to select the first artist when the artists are available

 gnomemusic/coremodel.py                       |  2 +-
 gnomemusic/grilowrappers/grltrackerwrapper.py |  2 +-
 gnomemusic/views/artistsview.py               | 18 +++++++++++++-----
 3 files changed, 15 insertions(+), 7 deletions(-)
---
diff --git a/gnomemusic/coremodel.py b/gnomemusic/coremodel.py
index ef3b19ce..897fe2e8 100644
--- a/gnomemusic/coremodel.py
+++ b/gnomemusic/coremodel.py
@@ -65,7 +65,6 @@ class CoreModel(GObject.GObject):
     """
 
     __gsignals__ = {
-        "artists-loaded": (GObject.SignalFlags.RUN_FIRST, None, ()),
         "playlist-loaded": (GObject.SignalFlags.RUN_FIRST, None, (int,)),
         "smart-playlist-change": (GObject.SignalFlags.RUN_FIRST, None, ())
     }
@@ -73,6 +72,7 @@ class CoreModel(GObject.GObject):
     active_playlist = GObject.Property(type=Playlist, default=None)
     grilo = GObject.Property(type=CoreGrilo, default=None)
     songs_available = GObject.Property(type=bool, default=False)
+    artists_available = GObject.Property(type=bool, default=False)
 
     def __init__(self, application):
         """Initiate the CoreModel object
diff --git a/gnomemusic/grilowrappers/grltrackerwrapper.py b/gnomemusic/grilowrappers/grltrackerwrapper.py
index 22e7796f..b4c163e3 100644
--- a/gnomemusic/grilowrappers/grltrackerwrapper.py
+++ b/gnomemusic/grilowrappers/grltrackerwrapper.py
@@ -499,7 +499,7 @@ class GrlTrackerWrapper(GObject.GObject):
             if not media:
                 self._artists_model.splice(
                     self._artists_model.get_n_items(), 0, artists_added)
-                self._coremodel.emit("artists-loaded")
+                self._coremodel.props.artists_available = True
                 self._window.notifications_popup.pop_loading()
                 return
 
diff --git a/gnomemusic/views/artistsview.py b/gnomemusic/views/artistsview.py
index a5454ae5..7a25b107 100644
--- a/gnomemusic/views/artistsview.py
+++ b/gnomemusic/views/artistsview.py
@@ -53,6 +53,7 @@ class ArtistsView(BaseView):
         self._artists = {}
 
         self._selected_artist = None
+        self._loaded_artists = []
 
         self._window = application.props.window
         self._coremodel = application.props.coremodel
@@ -61,8 +62,13 @@ class ArtistsView(BaseView):
         self._model.connect_after(
             "items-changed", self._on_model_items_changed)
         self._sidebar.bind_model(self._model, self._create_widget)
-        self._loaded_id = self._coremodel.connect(
-            "artists-loaded", self._on_artists_loaded)
+
+        if self._coremodel.props.artists_available is False:
+            self._loaded_id = self._coremodel.connect(
+                "notify::artists-available", self._on_artists_available)
+        else:
+            self._loaded_id = 0
+            self._on_artists_available()
 
         sidebar_container.props.width_request = 220
         sidebar_container.get_style_context().add_class('sidebar')
@@ -74,7 +80,6 @@ class ArtistsView(BaseView):
         self._ctrl.props.button = Gdk.BUTTON_PRIMARY
         self._ctrl.connect("released", self._on_sidebar_clicked)
 
-        self._loaded_artists = []
         self._loading_id = 0
 
         self.show_all()
@@ -112,8 +117,11 @@ class ArtistsView(BaseView):
         removed_frame = self._view.get_child_by_name(removed_artist)
         self._view.remove(removed_frame)
 
-    def _on_artists_loaded(self, klass):
-        self._coremodel.disconnect(self._loaded_id)
+    def _on_artists_available(self, klass=None, value=None):
+        if self._loaded_id > 0:
+            self._coremodel.disconnect(self._loaded_id)
+            self._loaded_id = 0
+
         first_row = self._sidebar.get_row_at_index(0)
         if first_row is None:
             return