Refactor catch default piece to allow reuse

But Fruit in-place update is still incomplete,
as child drawables are recreated when reused.

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableDroplet.cs

@@ -28,10 +28,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         {
             ScaleContainer.Child = new SkinnableDrawable(
                 new CatchSkinComponent(CatchSkinComponents.Droplet),
-                _ => new DropletPiece
+                _ => new DropletPiece());
-                {
-                    HyperDash = { BindTarget = HyperDash },
-                });
         }
 
         protected override void UpdateInitialTransforms()

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableFruit.cs

@@ -36,11 +36,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
 
             ScaleContainer.Child = new SkinnableDrawable(
                 new CatchSkinComponent(this is DrawableBanana ? CatchSkinComponents.Banana : CatchSkinComponents.Fruit),
-                _ => new FruitPiece
+                _ => new FruitPiece());
-                {
-                    VisualRepresentation = { BindTarget = VisualRepresentation },
-                    HyperDash = { BindTarget = HyperDash },
-                });
         }
 
         protected override void UpdateInitialTransforms()

osu.Game.Rulesets.Catch/Objects/Drawables/Pieces/CatchHitObjectPiece.cs

@@ -0,0 +1,54 @@
+// 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 System;
+using JetBrains.Annotations;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Rulesets.Objects.Drawables;
+using osuTK.Graphics;
+
+namespace osu.Game.Rulesets.Catch.Objects.Drawables.Pieces
+{
+    public class CatchHitObjectPiece : CompositeDrawable
+    {
+        public readonly Bindable<Color4> AccentColour = new Bindable<Color4>();
+        public readonly Bindable<bool> HyperDash = new Bindable<bool>();
+
+        [Resolved(canBeNull: true)]
+        private DrawableHitObject drawableHitObject { get; set; }
+
+        [CanBeNull]
+        protected DrawablePalpableCatchHitObject DrawableHitObject => (DrawablePalpableCatchHitObject)drawableHitObject;
+
+        [CanBeNull]
+        protected BorderPiece BorderPiece;
+
+        [CanBeNull]
+        protected HyperBorderPiece HyperBorderPiece;
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            if (DrawableHitObject != null)
+            {
+                AccentColour.BindTo(DrawableHitObject.AccentColour);
+                HyperDash.BindTo(DrawableHitObject.HyperDash);
+            }
+
+            HyperDash.BindValueChanged(hyper =>
+            {
+                if (HyperBorderPiece != null)
+                    HyperBorderPiece.Alpha = hyper.NewValue ? 1 : 0;
+            }, true);
+        }
+
+        protected override void Update()
+        {
+            if (BorderPiece != null && DrawableHitObject?.HitObject != null)
+                BorderPiece.Alpha = (float)Math.Clamp((DrawableHitObject.HitObject.StartTime - Time.Current) / 500, 0, 1);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Objects/Drawables/Pieces/DropletPiece.cs

@@ -1,37 +1,26 @@
 // 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.Allocation;
-using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Game.Rulesets.Objects.Drawables;
 using osuTK;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables.Pieces
 {
-    public class DropletPiece : CompositeDrawable
+    public class DropletPiece : CatchHitObjectPiece
     {
-        public readonly Bindable<bool> HyperDash = new Bindable<bool>();
-
         public DropletPiece()
         {
             Size = new Vector2(CatchHitObject.OBJECT_RADIUS / 2);
-        }
 
-        [BackgroundDependencyLoader]
+            InternalChildren = new Drawable[]
-        private void load(DrawableHitObject drawableObject)
-        {
-            InternalChild = new Pulp
             {
-                RelativeSizeAxes = Axes.Both,
+                new Pulp
-                AccentColour = { BindTarget = drawableObject.AccentColour }
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    AccentColour = { BindTarget = AccentColour }
+                },
+                HyperBorderPiece = new HyperDropletBorderPiece()
             };
-
-            if (HyperDash.Value)
-            {
-                AddInternal(new HyperDropletBorderPiece());
-            }
         }
     }
 }

osu.Game.Rulesets.Catch/Objects/Drawables/Pieces/FruitPiece.cs

@@ -1,17 +1,12 @@
 // 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 System;
-using JetBrains.Annotations;
-using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Game.Rulesets.Objects.Drawables;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables.Pieces
 {
-    internal class FruitPiece : CompositeDrawable
+    internal class FruitPiece : CatchHitObjectPiece
     {
         /// <summary>
         /// Because we're adding a border around the fruit, we need to scale down some.
@@ -19,38 +14,36 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables.Pieces
         public const float RADIUS_ADJUST = 1.1f;
 
         public readonly Bindable<FruitVisualRepresentation> VisualRepresentation = new Bindable<FruitVisualRepresentation>();
-        public readonly Bindable<bool> HyperDash = new Bindable<bool>();
-
-        [CanBeNull]
-        private DrawableCatchHitObject drawableHitObject;
-
-        [CanBeNull]
-        private BorderPiece borderPiece;
 
         public FruitPiece()
         {
             RelativeSizeAxes = Axes.Both;
         }
 
-        [BackgroundDependencyLoader(permitNulls: true)]
+        protected override void LoadComplete()
-        private void load([CanBeNull] DrawableHitObject drawable)
         {
-            drawableHitObject = (DrawableCatchHitObject)drawable;
+            base.LoadComplete();
+
+            if (DrawableHitObject != null)
+            {
+                var fruit = (DrawableFruit)DrawableHitObject;
+                VisualRepresentation.BindTo(fruit.VisualRepresentation);
+            }
+
+            VisualRepresentation.BindValueChanged(_ => recreateChildren(), true);
+        }
+
+        private void recreateChildren()
+        {
+            ClearInternal();
 
             AddInternal(getFruitFor(VisualRepresentation.Value));
 
-            // if it is not part of a DHO, the border is always invisible.
+            if (DrawableHitObject != null)
-            if (drawableHitObject != null)
+                AddInternal(BorderPiece = new BorderPiece());
-                AddInternal(borderPiece = new BorderPiece());
 
             if (HyperDash.Value)
-                AddInternal(new HyperBorderPiece());
+                AddInternal(HyperBorderPiece = new HyperBorderPiece());
-        }
-
-        protected override void Update()
-        {
-            if (borderPiece != null && drawableHitObject?.HitObject != null)
-                borderPiece.Alpha = (float)Math.Clamp((drawableHitObject.HitObject.StartTime - Time.Current) / 500, 0, 1);
         }
 
         private Drawable getFruitFor(FruitVisualRepresentation representation)
@@ -66,9 +59,6 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables.Pieces
                 case FruitVisualRepresentation.Pineapple:
                     return new PineapplePiece();
 
-                case FruitVisualRepresentation.Banana:
-                    return new BananaPiece();
-
                 case FruitVisualRepresentation.Raspberry:
                     return new RaspberryPiece();
             }