Fix crashes when batch downloading

The callbacks from AdapterManager.batch_download_songs happen on a
separate thread, which means any GTK-related functions must be avoided.

sublime_music/ui/artists.py

@@ -465,13 +465,17 @@ class ArtistDetailPanel(Gtk.Box):
     def on_download_all_click(self, _):
         AdapterManager.batch_download_songs(
             self.get_artist_song_ids(),
-            before_download=lambda _: self.update_artist_view(
+            before_download=lambda _: GLib.idle_add(
+                lambda: self.update_artist_view(
                     self.artist_id,
                     order_token=self.update_order_token,
+                )
             ),
-            on_song_download_complete=lambda _: self.update_artist_view(
+            on_song_download_complete=lambda _: GLib.idle_add(
+                lambda: self.update_artist_view(
                     self.artist_id,
                     order_token=self.update_order_token,
+                )
             ),
         )
 

sublime_music/ui/browse.py

@@ -440,7 +440,7 @@ class MusicDirectoryList(Gtk.Box):
         self.loading_indicator.hide()
 
     def on_download_state_change(self, _):
-        self.update()
+        GLib.idle_add(self.update)
 
     # Create Element Helper Functions
     # ==================================================================================

sublime_music/ui/common/album_with_songs.py

@@ -206,7 +206,7 @@ class AlbumWithSongs(Gtk.Box):
             allow_deselect = False
 
             def on_download_state_change(song_id: str):
-                self.update_album_songs(self.album.id)
+                GLib.idle_add(lambda: self.update_album_songs(self.album.id))
 
             # Use the new selection instead of the old one for calculating what
             # to do the right click on.
@@ -238,8 +238,8 @@ class AlbumWithSongs(Gtk.Box):
     def on_download_all_click(self, btn: Any):
         AdapterManager.batch_download_songs(
             [x[-1] for x in self.album_song_store],
-            before_download=lambda _: self.update(),
-            on_song_download_complete=lambda _: self.update(),
+            before_download=lambda _: GLib.idle_add(self.update),
+            on_song_download_complete=lambda _: GLib.idle_add(self.update),
         )
 
     def play_btn_clicked(self, btn: Any):