Yeah, I can use AsyncCall. If I have to. I guess.

The uninstall-game dialog computes folder sizes one at  time. With this commit, it updates the UI for each one as it completes, instead of waiting for the whole set to be done.

 Looks nicer this way.

lutris/gui/dialogs/uninstall_game.py

@@ -1,7 +1,7 @@
 # pylint: disable=no-member
 import os
 from gettext import gettext as _
-from typing import Callable, Dict, Iterable, List
+from typing import Callable, Iterable, List
 
 from gi.repository import GObject, Gtk
 
@@ -92,16 +92,19 @@ class UninstallMultipleGamesDialog(Gtk.Dialog):
     def update_folder_sizes(self, new_games: List[Game]) -> None:
         """Starts fetching folder sizes for new games added to the dialog; we only
         do this for the games given in 'new_games', however."""
-        folders_to_size = set()
+        folders_to_size = []
+        folders_seen = set()
 
         for row in self.uninstall_game_list.get_children():
             game = row.game
             if game in new_games and game.is_installed and game.directory:
-                folders_to_size.add(game.directory)
+                if game.directory not in folders_seen:
+                    folders_seen.add(game.directory)
+                    folders_to_size.append(game.directory)
                 row.show_folder_size_spinner()
 
         if folders_to_size:
-            AsyncCall(self._get_disk_size, self._folder_size_cb, folders_to_size)
+            AsyncCall(self._get_next_folder_size, self._get_next_folder_size_cb, folders_to_size)
 
     def update_subtitle(self) -> None:
         """Updates the dialog subtitle according to what games are being removed."""
@@ -266,21 +269,26 @@ class UninstallMultipleGamesDialog(Gtk.Dialog):
             self.destroy()
 
     @staticmethod
-    def _get_disk_size(directories: List[str]) -> Dict[str, int]:
-        folder_sizes = {}
-        for directory in directories:
-            folder_sizes[directory] = get_disk_size(directory)
-        return folder_sizes
+    def _get_next_folder_size(directories):
+        """This runs on a thread and computes the size of the first directory in
+        directories; the _get_next_folder_size_cb will run this again if required,
+        until all directories have been sized."""
+        directory = directories.pop(0)
+        size = get_disk_size(directory)
+        return directory, size, directories
 
-    def _folder_size_cb(self, folder_sizes: Dict[str, int], error):
+    def _get_next_folder_size_cb(self, result, error):
         if error:
             logger.error(error)
             return
 
+        directory, size, remaining_directories = result
+
+        if remaining_directories:
+            AsyncCall(self._get_next_folder_size, self._get_next_folder_size_cb, remaining_directories)
+
         for row in self.uninstall_game_list.get_children():
-            directory = row.game.directory
-            if directory and directory in folder_sizes:
-                size = folder_sizes[row.game.directory]
+            if directory == row.game.directory:
                 row.show_folder_size(size)
 
     class GameRemovalRow(Gtk.ListBoxRow):