Implement drafted new UI.

Assets/Cryville/Crtr/Browsing/UI/BrowserTabLayout.cs

@@ -0,0 +1,100 @@
+using Cryville.Common;
+using UnityEngine;
+using UnityEngine.EventSystems;
+using UnityEngine.UI;
+
+namespace Cryville.Crtr.Browsing.UI {
+	[ExecuteAlways]
+	internal class BrowserTabLayout : UIBehaviour, ILayoutElement {
+		[SerializeField]
+		float m_minWidth = 150;
+		public float MinWidth {
+			get { return m_minWidth; }
+			set {
+				if (m_minWidth == value) return;
+				m_minWidth = value;
+				UpdateTweener();
+			}
+		}
+
+		float m_layoutMinWidth = -1;
+		float ILayoutElement.minWidth { get { return m_layoutMinWidth; } }
+		void UpdateLayoutMinWidth(float value) {
+			if (m_layoutMinWidth == value) return;
+			m_layoutMinWidth = value;
+			SetDirty();
+		}
+
+		public float preferredWidth { get { return -1; } }
+		public float flexibleWidth { get { return -1; } }
+		public float minHeight { get { return -1; } }
+		public float preferredHeight { get { return -1; } }
+		public float flexibleHeight { get { return -1; } }
+		public int layoutPriority { get { return 1; } }
+
+		bool m_selected;
+		public bool Selected {
+			get { return m_selected; }
+			set {
+				if (m_selected == value) return;
+				m_selected = value;
+				UpdateTweener();
+			}
+		}
+
+		[SerializeField]
+		float m_tweenDuration = 0.2f;
+
+		PropertyTweener<float> _tweener;
+		void UpdateTweener() {
+			var width = MinWidth;
+			if (Selected) {
+				var preferredWidth = LayoutUtility.GetPreferredWidth(transform as RectTransform);
+				if (preferredWidth > width) width = preferredWidth;
+			}
+			_tweener.Start(width, m_tweenDuration);
+		}
+		void Update() {
+			_tweener.Advance(Time.deltaTime);
+		}
+
+		public void CalculateLayoutInputHorizontal() { }
+		public void CalculateLayoutInputVertical() { }
+
+		protected override void OnEnable() {
+			base.OnEnable();
+			m_layoutMinWidth = Selected ? -1 : MinWidth;
+			if (_tweener == null)
+				_tweener = new PropertyTweener<float>(
+					() => m_layoutMinWidth,
+					v => UpdateLayoutMinWidth(v),
+					Tweeners.Float.With(EasingFunctions.OutQuad)
+				);
+			SetDirty();
+		}
+		protected override void OnBeforeTransformParentChanged() {
+			base.OnBeforeTransformParentChanged();
+			SetDirty();
+		}
+		protected override void OnTransformParentChanged() {
+			base.OnTransformParentChanged();
+			SetDirty();
+		}
+		protected override void OnDidApplyAnimationProperties() {
+			base.OnDidApplyAnimationProperties();
+			SetDirty();
+		}
+		protected override void OnValidate() {
+			base.OnValidate();
+			SetDirty();
+		}
+		protected override void OnDisable() {
+			SetDirty();
+			base.OnDisable();
+		}
+		void SetDirty() {
+			if (!IsActive()) return;
+			LayoutRebuilder.MarkLayoutForRebuild(transform as RectTransform);
+		}
+	}
+}