Make GameBeatmap late-bind its AudioManager for ctor Beatmap access

osu.Game/Beatmaps/GameBeatmap.cs

@@ -1,8 +1,11 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using System;
 using System.Diagnostics;
+using JetBrains.Annotations;
 using osu.Framework.Audio;
+using osu.Framework.Audio.Track;
 using osu.Framework.Configuration;
 
 namespace osu.Game.Beatmaps
@@ -11,18 +14,31 @@ namespace osu.Game.Beatmaps
     /// A <see cref="Bindable{WorkingBeatmap}"/> for the <see cref="OsuGame"/> beatmap.
     /// This should be used sparingly in-favour of <see cref="IGameBeatmap"/>.
     /// </summary>
-    public class GameBeatmap : NonNullableBindable<WorkingBeatmap>, IGameBeatmap
+    public abstract class GameBeatmap : NonNullableBindable<WorkingBeatmap>, IGameBeatmap
     {
-        private readonly AudioManager audioManager;
+        private AudioManager audioManager;
-
         private WorkingBeatmap lastBeatmap;
 
-        public GameBeatmap(WorkingBeatmap defaultValue, AudioManager audioManager)
+        protected GameBeatmap(WorkingBeatmap defaultValue)
             : base(defaultValue)
         {
+        }
+
+        /// <summary>
+        /// Registers an <see cref="AudioManager"/> for <see cref="Track"/>s to be added to.
+        /// </summary>
+        /// <param name="audioManager">The <see cref="AudioManager"/>.</param>
+        protected void RegisterAudioManager([NotNull] AudioManager audioManager)
+        {
+            if (this.audioManager != null) throw new InvalidOperationException($"Cannot register multiple {nameof(AudioManager)}s.");
+
             this.audioManager = audioManager;
 
             ValueChanged += registerAudioTrack;
+
+            // If the track has changed prior to this being called, let's register it
+            if (Value != Default)
+                registerAudioTrack(Value);
         }
 
         private void registerAudioTrack(WorkingBeatmap beatmap)
@@ -46,17 +62,14 @@ namespace osu.Game.Beatmaps
             lastBeatmap = beatmap;
         }
 
+        [NotNull]
         IGameBeatmap IGameBeatmap.GetBoundCopy() => GetBoundCopy();
 
         /// <summary>
         /// Retrieve a new <see cref="GameBeatmap"/> instance weakly bound to this <see cref="GameBeatmap"/>.
         /// If you are further binding to events of the retrieved <see cref="GameBeatmap"/>, ensure a local reference is held.
         /// </summary>
-        public new GameBeatmap GetBoundCopy()
+        [NotNull]
-        {
+        public abstract GameBeatmap GetBoundCopy();
-            var copy = new GameBeatmap(Default, audioManager);
-            copy.BindTo(this);
-            return copy;
-        }
     }
 }

osu.Game/OsuGameBase.cs

@@ -64,7 +64,8 @@ namespace osu.Game
 
         protected override Container<Drawable> Content => content;
 
-        protected GameBeatmap Beatmap;
+        private OsuGameBeatmap beatmap;
+        protected GameBeatmap Beatmap => beatmap;
 
         private Bindable<bool> fpsDisplayVisible;
 
@@ -156,15 +157,15 @@ namespace osu.Game
             Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Venera-Light"));
 
             var defaultBeatmap = new DummyWorkingBeatmap(this);
-            Beatmap = new GameBeatmap(defaultBeatmap, Audio);
+            beatmap = new OsuGameBeatmap(defaultBeatmap, Audio);
             BeatmapManager.DefaultBeatmap = defaultBeatmap;
 
             // tracks play so loud our samples can't keep up.
             // this adds a global reduction of track volume for the time being.
             Audio.Track.AddAdjustment(AdjustableProperty.Volume, new BindableDouble(0.8));
 
-            dependencies.Cache(Beatmap);
+            dependencies.CacheAs<GameBeatmap>(beatmap);
-            dependencies.CacheAs<IGameBeatmap>(Beatmap);
+            dependencies.CacheAs<IGameBeatmap>(beatmap);
 
             FileStore.Cleanup();
 
@@ -235,5 +236,26 @@ namespace osu.Game
         }
 
         public string[] HandledExtensions => fileImporters.SelectMany(i => i.HandledExtensions).ToArray();
+
+        private class OsuGameBeatmap : GameBeatmap
+        {
+            public OsuGameBeatmap(WorkingBeatmap defaultValue, AudioManager audioManager)
+                : this(defaultValue)
+            {
+                RegisterAudioManager(audioManager);
+            }
+
+            private OsuGameBeatmap(WorkingBeatmap defaultValue)
+                : base(defaultValue)
+            {
+            }
+
+            public override GameBeatmap GetBoundCopy()
+            {
+                var copy = new OsuGameBeatmap(Default);
+                copy.BindTo(this);
+                return copy;
+            }
+        }
     }
 }

osu.Game/Tests/Visual/OsuTestCase.cs

@@ -12,31 +12,35 @@ namespace osu.Game.Tests.Visual
 {
     public abstract class OsuTestCase : TestCase
     {
-        protected GameBeatmap Beatmap { get; private set; }
+        private readonly OsuTestBeatmap beatmap = new OsuTestBeatmap(new DummyWorkingBeatmap());
+        protected GameBeatmap Beatmap => beatmap;
 
         private DependencyContainer dependencies;
 
         protected override IReadOnlyDependencyContainer CreateLocalDependencies(IReadOnlyDependencyContainer parent)
         {
-            // The beatmap is constructed here rather than load() because our children get dependencies injected before our load() runs
-            Beatmap = new GameBeatmap(new DummyWorkingBeatmap(), parent.Get<AudioManager>());
-
             dependencies = new DependencyContainer(base.CreateLocalDependencies(parent));
 
-            dependencies.CacheAs<IGameBeatmap>(Beatmap);
+            dependencies.CacheAs<GameBeatmap>(beatmap);
-            dependencies.Cache(Beatmap);
+            dependencies.CacheAs<IGameBeatmap>(beatmap);
 
             return dependencies;
         }
 
+        [BackgroundDependencyLoader]
+        private void load(AudioManager audioManager)
+        {
+            beatmap.SetAudioManager(audioManager);
+        }
+
         protected override void Dispose(bool isDisposing)
         {
             base.Dispose(isDisposing);
 
-            if (Beatmap != null)
+            if (beatmap != null)
             {
-                Beatmap.Disabled = true;
+                beatmap.Disabled = true;
-                Beatmap.Value.Track.Stop();
+                beatmap.Value.Track.Stop();
             }
         }
 
@@ -58,5 +62,22 @@ namespace osu.Game.Tests.Visual
 
             public void RunTestBlocking(TestCase test) => runner.RunTestBlocking(test);
         }
+
+        private class OsuTestBeatmap : GameBeatmap
+        {
+            public OsuTestBeatmap(WorkingBeatmap defaultValue)
+                : base(defaultValue)
+            {
+            }
+
+            public void SetAudioManager(AudioManager audioManager) => RegisterAudioManager(audioManager);
+
+            public override GameBeatmap GetBoundCopy()
+            {
+                var copy = new OsuTestBeatmap(Default);
+                copy.BindTo(this);
+                return copy;
+            }
+        }
     }
 }