Add a dummy beatmap provider for use in BeatmapInfoWedge

osu.Game/Beatmaps/DummyWorkingBeatmap.cs

@@ -0,0 +1,37 @@
+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using System.Collections.Generic;
+using osu.Framework.Audio.Track;
+using osu.Framework.Graphics.Textures;
+using osu.Game.Database;
+using osu.Game.Rulesets.Objects;
+
+namespace osu.Game.Beatmaps
+{
+    internal class DummyWorkingBeatmap : WorkingBeatmap
+    {
+        public DummyWorkingBeatmap()
+            : base(new BeatmapInfo
+            {
+                Metadata = new BeatmapMetadata
+                {
+                    Artist = "please load a beatmap!",
+                    Title = "no beatmaps available!",
+                    Author = "no one",
+                },
+                Difficulty = new BeatmapDifficulty(),
+            })
+        {
+        }
+
+        protected override Beatmap GetBeatmap() => new Beatmap
+        {
+            HitObjects = new List<HitObject>(),
+        };
+
+        protected override Texture GetBackground() => null;
+
+        protected override Track GetTrack() => null;
+    }
+}

osu.Game/Screens/Select/BeatmapInfoWedge.cs

@@ -45,6 +45,14 @@ namespace osu.Game.Screens.Select
             };
         }
 
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            State = Visibility.Visible;
+            AlwaysPresent = true;
+        }
+
         protected override bool HideOnEscape => false;
 
         protected override bool BlockPassThroughMouse => false;
@@ -63,17 +71,8 @@ namespace osu.Game.Screens.Select
 
         public void UpdateBeatmap(WorkingBeatmap beatmap)
         {
-            if (beatmap?.BeatmapInfo == null)
-            {
-                State = Visibility.Hidden;
-                beatmapInfoContainer?.FadeOut(250);
-                beatmapInfoContainer?.Expire();
-                beatmapInfoContainer = null;
-                return;
-            }
-
-            State = Visibility.Visible;
-            AlwaysPresent = true;
+            if (beatmap == null)
+                beatmap = new DummyWorkingBeatmap();
 
             var lastContainer = beatmapInfoContainer;
             float newDepth = lastContainer?.Depth + 1 ?? 0;
@@ -124,7 +123,8 @@ namespace osu.Game.Screens.Select
                     }));
 
                     //get statistics from the current ruleset.
-                    labels.AddRange(beatmapInfo.Ruleset.CreateInstance().GetBeatmapStatistics(beatmap).Select(s => new InfoLabel(s)));
+                    if (beatmapInfo.Ruleset != null)
+                        labels.AddRange(beatmapInfo.Ruleset.CreateInstance().GetBeatmapStatistics(beatmap).Select(s => new InfoLabel(s)));
                 }
 
                 PixelSnapping = true;

osu.Game/osu.Game.csproj

@@ -76,6 +76,7 @@
     <Compile Include="Audio\SampleInfoList.cs" />
     <Compile Include="Beatmaps\Drawables\BeatmapBackgroundSprite.cs" />
     <Compile Include="Beatmaps\DifficultyCalculator.cs" />
+    <Compile Include="Beatmaps\DummyWorkingBeatmap.cs" />
     <Compile Include="Graphics\Containers\OsuClickableContainer.cs" />
     <Compile Include="Graphics\Containers\OsuFocusedOverlayContainer.cs" />
     <Compile Include="Graphics\Containers\OsuScrollContainer.cs" />
@@ -538,4 +539,4 @@
   <Target Name="AfterBuild">
   </Target>
   -->
-</Project>
+</Project>