// 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.Diagnostics; using osu.Framework.Bindables; using osu.Framework.Graphics; using osu.Framework.Graphics.Containers; using osu.Framework.Graphics.Pooling; using osu.Framework.Input.Events; using osuTK; namespace osu.Game.Screens.Select.Carousel { public abstract partial class DrawableCarouselItem : PoolableDrawable { public const float MAX_HEIGHT = 80; public override bool IsPresent => base.IsPresent || Item?.Visible == true; public override bool HandlePositionalInput => Item?.Visible == true; public override bool PropagatePositionalInputSubTree => Item?.Visible == true; public readonly CarouselHeader Header; /// <summary> /// Optional content which sits below the header. /// </summary> protected readonly Container<Drawable> Content; protected readonly Container MovementContainer; public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => Header.ReceivePositionalInputAt(screenSpacePos); private CarouselItem? item; public CarouselItem? Item { get => item; set { if (item == value) return; if (item != null) { item.Filtered.ValueChanged -= onStateChange; item.State.ValueChanged -= onStateChange; Header.State.UnbindFrom(item.State); if (item is CarouselGroup group) { foreach (var c in group.Items) c.Filtered.ValueChanged -= onStateChange; } } item = value; if (IsLoaded && !IsDisposed) UpdateItem(); } } protected DrawableCarouselItem() { RelativeSizeAxes = Axes.X; Alpha = 0; InternalChildren = new Drawable[] { MovementContainer = new Container { RelativeSizeAxes = Axes.Both, Children = new Drawable[] { Header = new CarouselHeader(), Content = new Container { RelativeSizeAxes = Axes.Both, } } }, }; } public void SetMultiplicativeAlpha(float alpha) => Header.BorderContainer.Alpha = alpha; protected override void LoadComplete() { base.LoadComplete(); UpdateItem(); } protected override void Update() { base.Update(); Content.Y = Header.Height; } protected virtual void UpdateItem() { if (Item == null) return; Scheduler.AddOnce(ApplyState); Item.Filtered.ValueChanged += onStateChange; Item.State.ValueChanged += onStateChange; Header.State.BindTo(Item.State); if (Item is CarouselGroup group) { foreach (var c in group.Items) c.Filtered.ValueChanged += onStateChange; } } private void onStateChange(ValueChangedEvent<CarouselItemState> obj) => Scheduler.AddOnce(ApplyState); private void onStateChange(ValueChangedEvent<bool> _) => Scheduler.AddOnce(ApplyState); protected virtual void ApplyState() { Debug.Assert(Item != null); // Use the fact that we know the precise height of the item from the model to avoid the need for AutoSize overhead. // Additionally, AutoSize doesn't work well due to content starting off-screen and being masked away. Height = Item.TotalHeight; switch (Item.State.Value) { case CarouselItemState.NotSelected: Deselected(); break; case CarouselItemState.Selected: Selected(); break; } if (!Item.Visible) this.FadeOut(100, Easing.OutQuint); else this.FadeIn(400, Easing.OutQuint); } protected virtual void Selected() { Debug.Assert(Item != null); } protected virtual void Deselected() { } protected override bool OnClick(ClickEvent e) { Debug.Assert(Item != null); Item.State.Value = CarouselItemState.Selected; return true; } protected override void Dispose(bool isDisposing) { base.Dispose(isDisposing); // This is important to clean up event subscriptions. Item = null; } } }