Unity Project

reference
https://cardgames.io/yahtzee/

Library/PackageCache/com.unity.timeline@1.2.15/Editor/treeview/Drawers/TrackDrawer.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+using UnityEngine.Playables;
+using UnityEngine.Timeline;
+namespace UnityEditor.Timeline
+{
+    class TrackDrawer : GUIDrawer
+    {
+        internal WindowState sequencerState { get; set; }
+
+
+        public static TrackDrawer CreateInstance(TrackAsset trackAsset)
+        {
+            if (trackAsset == null)
+                return Activator.CreateInstance<TrackDrawer>();
+
+            TrackDrawer drawer;
+
+            try
+            {
+                drawer = (TrackDrawer)Activator.CreateInstance(TimelineHelpers.GetCustomDrawer(trackAsset.GetType()));
+            }
+            catch (Exception)
+            {
+                drawer = Activator.CreateInstance<TrackDrawer>();
+            }
+
+            drawer.track = trackAsset;
+            return drawer;
+        }
+
+        protected TrackAsset track { get; private set; }
+
+        public virtual bool DrawTrackHeaderButton(Rect rect, TrackAsset track, WindowState state)
+        {
+            return false;
+        }
+
+        public virtual bool DrawTrack(Rect trackRect, TrackAsset trackAsset, Vector2 visibleTime, WindowState state)
+        {
+            return false;
+        }
+
+        public virtual void DrawRecordingBackground(Rect trackRect, TrackAsset trackAsset, Vector2 visibleTime, WindowState state)
+        {
+            EditorGUI.DrawRect(trackRect, DirectorStyles.Instance.customSkin.colorTrackBackgroundRecording);
+        }
+    }
+}