Initial room background implementation

osu.Game/Screens/OnlinePlay/Components/OnlinePlayBackgroundScreen.cs

@@ -1,57 +1,47 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-#nullable enable
-
-using System.Linq;
 using System.Threading;
 using osu.Framework.Allocation;
-using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Screens;
 using osu.Game.Online.Rooms;
 using osuTK;
 
+#nullable enable
+
 namespace osu.Game.Screens.OnlinePlay.Components
 {
-    public class RoomBackgroundScreen : BackgroundScreen
+    public abstract class OnlinePlayBackgroundScreen : BackgroundScreen
     {
         private CancellationTokenSource? cancellationSource;
         private PlaylistItemBackground? background;
 
-        private readonly BindableList<PlaylistItem> playlist = new BindableList<PlaylistItem>();
-
-        public RoomBackgroundScreen()
+        protected OnlinePlayBackgroundScreen()
             : base(false)
         {
-            playlist.BindCollectionChanged((_, __) => updateBackground());
         }
 
         [BackgroundDependencyLoader]
         private void load()
         {
-            switchBackground(new PlaylistItemBackground(null));
+            switchBackground(new PlaylistItemBackground(playlistItem));
         }
 
-        private Room? room;
+        private PlaylistItem? playlistItem;
 
-        public Room? Room
+        protected PlaylistItem? PlaylistItem
         {
-            get => room;
+            get => playlistItem;
             set
             {
-                if (room == value)
+                if (playlistItem == value)
                     return;
 
-                if (room != null)
-                    playlist.UnbindFrom(room.Playlist);
+                playlistItem = value;
 
-                room = value;
-
-                if (room != null)
-                    playlist.BindTo(room.Playlist);
-                else
-                    playlist.Clear();
+                if (LoadState > LoadState.Ready)
+                    updateBackground();
             }
         }
 
@@ -59,7 +49,6 @@ namespace osu.Game.Screens.OnlinePlay.Components
         {
             Schedule(() =>
             {
-                var playlistItem = playlist.FirstOrDefault();
                 var beatmap = playlistItem?.Beatmap.Value;
 
                 if (background?.BeatmapInfo?.BeatmapSet?.OnlineInfo?.Covers?.Cover == beatmap?.BeatmapSet?.OnlineInfo?.Covers?.Cover)

osu.Game/Screens/OnlinePlay/Lounge/LoungeBackgroundScreen.cs

@@ -0,0 +1,45 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+#nullable enable
+
+using System.Linq;
+using osu.Framework.Bindables;
+using osu.Game.Online.Rooms;
+using osu.Game.Screens.OnlinePlay.Components;
+using PlaylistItem = osu.Game.Online.Rooms.PlaylistItem;
+
+namespace osu.Game.Screens.OnlinePlay.Lounge
+{
+    public class LoungeBackgroundScreen : OnlinePlayBackgroundScreen
+    {
+        private readonly BindableList<PlaylistItem> playlist = new BindableList<PlaylistItem>();
+
+        public LoungeBackgroundScreen()
+        {
+            playlist.BindCollectionChanged((_, __) => PlaylistItem = playlist.FirstOrDefault());
+        }
+
+        private Room? selectedRoom;
+
+        public Room? SelectedRoom
+        {
+            get => selectedRoom;
+            set
+            {
+                if (selectedRoom == value)
+                    return;
+
+                if (selectedRoom != null)
+                    playlist.UnbindFrom(selectedRoom.Playlist);
+
+                selectedRoom = value;
+
+                if (selectedRoom != null)
+                    playlist.BindTo(selectedRoom.Playlist);
+                else
+                    playlist.Clear();
+            }
+        }
+    }
+}

osu.Game/Screens/OnlinePlay/Lounge/LoungeSubScreen.cs

@@ -36,7 +36,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
     {
         public override string Title => "Lounge";
 
-        protected override BackgroundScreen CreateBackground() => new RoomBackgroundScreen();
+        protected override BackgroundScreen CreateBackground() => new LoungeBackgroundScreen();
 
         protected override UserActivity InitialActivity => new UserActivity.SearchingForLobby();
 
@@ -169,7 +169,7 @@ namespace osu.Game.Screens.OnlinePlay.Lounge
                 if (drawable != null)
                     scrollContainer.ScrollIntoView(drawable);
 
-                ApplyToBackground(b => ((RoomBackgroundScreen)b).Room = val.NewValue);
+                ApplyToBackground(b => ((LoungeBackgroundScreen)b).SelectedRoom = val.NewValue);
             });
         }
 

osu.Game/Screens/OnlinePlay/Match/RoomBackgroundScreen.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Game.Online.Rooms;
+using osu.Game.Screens.OnlinePlay.Components;
+
+namespace osu.Game.Screens.OnlinePlay.Match
+{
+    public class RoomBackgroundScreen : OnlinePlayBackgroundScreen
+    {
+        public readonly Bindable<PlaylistItem> SelectedItem = new Bindable<PlaylistItem>();
+
+        public RoomBackgroundScreen()
+        {
+            SelectedItem.BindValueChanged(item => PlaylistItem = item.NewValue);
+        }
+    }
+}

osu.Game/Screens/OnlinePlay/Match/RoomSubScreen.cs

@@ -29,6 +29,11 @@ namespace osu.Game.Screens.OnlinePlay.Match
         [Cached(typeof(IBindable<PlaylistItem>))]
         protected readonly Bindable<PlaylistItem> SelectedItem = new Bindable<PlaylistItem>();
 
+        protected override BackgroundScreen CreateBackground() => new RoomBackgroundScreen
+        {
+            SelectedItem = { BindTarget = SelectedItem }
+        };
+
         public override bool DisallowExternalBeatmapRulesetChanges => true;
 
         /// <summary>