Refactor ExpandingControlContainer to no longer rely on controls

osu.Game.Tests/Visual/UserInterface/TestSceneExpandingContainer.cs

@@ -1,20 +1,16 @@
 // 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.Linq;
 using NUnit.Framework;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Framework.Testing;
-using osu.Game.Graphics.UserInterface;
 using osu.Game.Overlays;
 using osu.Game.Overlays.Settings.Sections;
 using osuTK;
-using osuTK.Input;
 
 namespace osu.Game.Tests.Visual.UserInterface
 {
-    public class TestSceneExpandingControlContainer : OsuManualInputManagerTestScene
+    public class TestSceneExpandingContainer : OsuManualInputManagerTestScene
     {
         private TestExpandingContainer container;
         private SettingsToolboxGroup toolboxGroup;
@@ -84,44 +80,22 @@ namespace osu.Game.Tests.Visual.UserInterface
         }
 
         /// <summary>
-        /// Tests hovering over controls expands the parenting container appropriately and does not contract until hover is lost from container.
+        /// Tests hovering expands the container and does not contract until hover is lost.
         /// </summary>
         [Test]
-        public void TestHoveringControlExpandsContainer()
+        public void TestHoveringExpandsContainer()
         {
             AddAssert("ensure container contracted", () => !container.Expanded.Value);
 
-            AddStep("hover slider", () => InputManager.MoveMouseTo(slider1));
+            AddStep("hover container", () => InputManager.MoveMouseTo(container));
             AddAssert("container expanded", () => container.Expanded.Value);
             AddAssert("controls expanded", () => slider1.Expanded.Value && slider2.Expanded.Value);
 
-            AddStep("hover group top", () => InputManager.MoveMouseTo(toolboxGroup.ScreenSpaceDrawQuad.TopLeft + new Vector2(5)));
-            AddAssert("container still expanded", () => container.Expanded.Value);
-            AddAssert("controls still expanded", () => slider1.Expanded.Value && slider2.Expanded.Value);
-
             AddStep("hover away", () => InputManager.MoveMouseTo(Vector2.Zero));
             AddAssert("container contracted", () => !container.Expanded.Value);
             AddAssert("controls contracted", () => !slider1.Expanded.Value && !slider2.Expanded.Value);
         }
 
-        /// <summary>
-        /// Tests dragging a UI control (e.g. <see cref="OsuSliderBar{T}"/>) outside its parenting container does not contract it until dragging is finished.
-        /// </summary>
-        [Test]
-        public void TestDraggingControlOutsideDoesntContractContainer()
-        {
-            AddStep("hover slider", () => InputManager.MoveMouseTo(slider1));
-            AddAssert("container expanded", () => container.Expanded.Value);
-
-            AddStep("hover slider nub", () => InputManager.MoveMouseTo(slider1.ChildrenOfType<Nub>().Single()));
-            AddStep("hold slider nub", () => InputManager.PressButton(MouseButton.Left));
-            AddStep("drag outside container", () => InputManager.MoveMouseTo(Vector2.Zero));
-            AddAssert("container still expanded", () => container.Expanded.Value);
-
-            AddStep("release slider nub", () => InputManager.ReleaseButton(MouseButton.Left));
-            AddAssert("container contracted", () => !container.Expanded.Value);
-        }
-
         /// <summary>
         /// Tests expanding a container will expand underlying groups if contracted.
         /// </summary>
@@ -157,21 +131,21 @@ namespace osu.Game.Tests.Visual.UserInterface
         }
 
         /// <summary>
-        /// Tests expanding a container via <see cref="ExpandingControlContainer{TControl}.Expanded"/> does not get contracted by losing hover.
+        /// Tests expanding a container via <see cref="ExpandingContainer.Expanded"/> does not get contracted by losing hover.
         /// </summary>
         [Test]
         public void TestExpandingContainerDoesntGetContractedByHover()
         {
             AddStep("expand container", () => container.Expanded.Value = true);
 
-            AddStep("hover control", () => InputManager.MoveMouseTo(slider1));
+            AddStep("hover container", () => InputManager.MoveMouseTo(container));
             AddAssert("container still expanded", () => container.Expanded.Value);
 
             AddStep("hover away", () => InputManager.MoveMouseTo(Vector2.Zero));
             AddAssert("container still expanded", () => container.Expanded.Value);
         }
 
-        private class TestExpandingContainer : ExpandingControlContainer<IExpandableControl>
+        private class TestExpandingContainer : ExpandingContainer
         {
             public TestExpandingContainer()
                 : base(120, 250)

osu.Game/Overlays/ExpandableSlider.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Overlays
     /// <summary>
     /// An <see cref="IExpandable"/> implementation for the UI slider bar control.
     /// </summary>
-    public class ExpandableSlider<T, TSlider> : CompositeDrawable, IExpandableControl, IHasCurrentValue<T>
+    public class ExpandableSlider<T, TSlider> : CompositeDrawable, IExpandable, IHasCurrentValue<T>
         where T : struct, IEquatable<T>, IComparable<T>, IConvertible
         where TSlider : OsuSliderBar<T>, new()
     {
@@ -72,8 +72,6 @@ namespace osu.Game.Overlays
 
         public BindableBool Expanded { get; } = new BindableBool();
 
-        bool IExpandable.ShouldBeExpanded => IsHovered || slider.IsDragged;
-
         public override bool HandlePositionalInput => true;
 
         public ExpandableSlider()

osu.Game/Overlays/ExpandingButtonContainer.cs

@@ -1,17 +1,15 @@
 // 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.Game.Graphics.UserInterface;
-
 namespace osu.Game.Overlays
 {
     /// <summary>
-    /// An <see cref="ExpandingControlContainer{TControl}"/> with a long hover expansion delay for buttons.
+    /// An <see cref="ExpandingContainer"/> with a long hover expansion delay.
     /// </summary>
     /// <remarks>
     /// Mostly used for buttons with explanatory labels, in which the label would display after a "long hover".
     /// </remarks>
-    public class ExpandingButtonContainer : ExpandingControlContainer<OsuButton>
+    public class ExpandingButtonContainer : ExpandingContainer
     {
         protected ExpandingButtonContainer(float contractedWidth, float expandedWidth)
             : base(contractedWidth, expandedWidth)

osu.Game/Overlays/ExpandingContainer.cs

@@ -1,23 +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 System.Linq;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Input.Events;
-using osu.Framework.Testing;
 using osu.Framework.Threading;
 using osu.Game.Graphics.Containers;
 
 namespace osu.Game.Overlays
 {
     /// <summary>
-    /// Represents a <see cref="Container"/> with the ability to expand/contract when hovering the controls within it.
+    /// Represents a <see cref="Container"/> with the ability to expand/contract on hover.
     /// </summary>
-    /// <typeparam name="TControl">The type of UI control to lookup for hover expansion.</typeparam>
+    public class ExpandingContainer : Container, IExpandingContainer
-    public class ExpandingControlContainer<TControl> : Container, IExpandingContainer
-        where TControl : class, IDrawable
     {
         private readonly float contractedWidth;
         private readonly float expandedWidth;
@@ -33,7 +29,7 @@ namespace osu.Game.Overlays
 
         protected FillFlowContainer FillFlow { get; }
 
-        protected ExpandingControlContainer(float contractedWidth, float expandedWidth)
+        protected ExpandingContainer(float contractedWidth, float expandedWidth)
         {
             this.contractedWidth = contractedWidth;
             this.expandedWidth = expandedWidth;
@@ -57,7 +53,6 @@ namespace osu.Game.Overlays
         }
 
         private ScheduledDelegate hoverExpandEvent;
-        private TControl activeControl;
 
         protected override void LoadComplete()
         {
@@ -69,61 +64,38 @@ namespace osu.Game.Overlays
             }, true);
         }
 
-        protected override void Update()
-        {
-            base.Update();
-
-            // if the container was expanded from hovering over a control, we have to check per-frame whether we can contract it back.
-            // that's because contracting the container depends not only on whether it's no longer hovered,
-            // but also on whether the hovered control is no longer in a dragged state (if it was).
-            if (hoverExpandEvent != null && !IsHovered && (activeControl == null || !isControlActive(activeControl)))
-            {
-                hoverExpandEvent?.Cancel();
-
-                Expanded.Value = false;
-                hoverExpandEvent = null;
-                activeControl = null;
-            }
-        }
-
         protected override bool OnHover(HoverEvent e)
         {
-            queueExpandIfHovering();
+            updateHoverExpansion();
             return true;
         }
 
         protected override bool OnMouseMove(MouseMoveEvent e)
         {
-            queueExpandIfHovering();
+            updateHoverExpansion();
             return base.OnMouseMove(e);
         }
 
-        private void queueExpandIfHovering()
+        protected override void OnHoverLost(HoverLostEvent e)
         {
-            // if the same control is hovered or dragged, let the scheduled expand play out..
+            if (hoverExpandEvent != null)
-            if (activeControl != null && isControlActive(activeControl))
+            {
+                hoverExpandEvent?.Cancel();
+                hoverExpandEvent = null;
+
+                Expanded.Value = false;
                 return;
+            }
 
-            // ..otherwise check whether a new control is hovered, and if so, queue a new hover operation.
+            base.OnHoverLost(e);
-            hoverExpandEvent?.Cancel();
-
-            // usually we wouldn't use ChildrenOfType in implementations, but this is the simplest way
-            // to handle cases like the editor where the controls may be nested within a child hierarchy.
-            activeControl = FillFlow.ChildrenOfType<TControl>().FirstOrDefault(isControlActive);
-
-            if (activeControl != null && !Expanded.Value)
-                hoverExpandEvent = Scheduler.AddDelayed(() => Expanded.Value = true, HoverExpansionDelay);
         }
 
-        /// <summary>
+        private void updateHoverExpansion()
-        /// Whether the given control is currently active, by checking whether it's hovered or dragged.
-        /// </summary>
-        private bool isControlActive(TControl control)
         {
-            if (control is IExpandable expandable)
+            hoverExpandEvent?.Cancel();
-                return expandable.ShouldBeExpanded;
 
-            return control.IsHovered || control.IsDragged;
+            if (IsHovered && !Expanded.Value)
+                hoverExpandEvent = Scheduler.AddDelayed(() => Expanded.Value = true, HoverExpansionDelay);
         }
     }
 }

osu.Game/Overlays/IExpandable.cs

@@ -3,7 +3,6 @@
 
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Game.Graphics.UserInterface;
 
 namespace osu.Game.Overlays
 {
@@ -16,15 +15,5 @@ namespace osu.Game.Overlays
         /// Whether this drawable is in an expanded state.
         /// </summary>
         BindableBool Expanded { get; }
-
-        /// <summary>
-        /// Whether this drawable should be/stay expanded by a parenting <see cref="IExpandingContainer"/>.
-        /// By default, this is <see langword="true"/> when this drawable is in a hovered or dragged state.
-        /// </summary>
-        /// <remarks>
-        /// This is defined for certain controls which may have a child handling dragging instead.
-        /// (e.g. <see cref="ExpandableSlider{T,TSlider}"/> in which dragging is handled by their underlying <see cref="OsuSliderBar{T}"/> control).
-        /// </remarks>
-        bool ShouldBeExpanded => IsHovered || IsDragged;
     }
 }

osu.Game/Overlays/IExpandableControl.cs

@@ -1,12 +0,0 @@
-// 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.
-
-namespace osu.Game.Overlays
-{
-    /// <summary>
-    /// An interface for UI controls with the ability to expand/contract.
-    /// </summary>
-    public interface IExpandableControl : IExpandable
-    {
-    }
-}