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Source/Editor/GUI/Timeline/Tracks/SingleMediaAssetTrack.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+using FlaxEditor.GUI.Timeline.Undo;
+using FlaxEditor.Scripting;
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.GUI.Timeline.Tracks
+{
+    /// <summary>
+    /// The timeline media that represents a media event with an asset reference.
+    /// </summary>
+    /// <seealso cref="FlaxEditor.GUI.Timeline.Media" />
+    public class SingleMediaAssetMedia : Media
+    {
+        /// <summary>
+        /// The asset id.
+        /// </summary>
+        public Guid Asset;
+    }
+
+    /// <summary>
+    /// The base class for timeline tracks that use single media with an asset reference.
+    /// </summary>
+    /// <typeparam name="TAsset">The type of the asset.</typeparam>
+    /// <typeparam name="TMedia">The type of the media event.</typeparam>
+    /// <seealso cref="FlaxEditor.GUI.Timeline.Track" />
+    public abstract class SingleMediaAssetTrack<TAsset, TMedia> : SingleMediaTrack<TMedia>
+    where TAsset : Asset
+    where TMedia : SingleMediaAssetMedia, new()
+    {
+        /// <summary>
+        /// The asset reference picker control.
+        /// </summary>
+        protected readonly AssetPicker _picker;
+
+        /// <summary>
+        /// Gets or sets the asset.
+        /// </summary>
+        public TAsset Asset
+        {
+            get => FlaxEngine.Content.LoadAsync<TAsset>(TrackMedia.Asset);
+            set
+            {
+                TMedia media = TrackMedia;
+                if (media.Asset == value?.ID)
+                    return;
+
+                media.Asset = value?.ID ?? Guid.Empty;
+                _picker.SelectedAsset = value;
+                OnAssetChanged();
+                Timeline?.MarkAsEdited();
+            }
+        }
+
+        /// <inheritdoc />
+        protected SingleMediaAssetTrack(ref TrackCreateOptions options)
+        : base(ref options)
+        {
+            var width = 50.0f;
+            var height = 36.0f;
+            _picker = new AssetPicker(new ScriptType(typeof(TAsset)), Vector2.Zero)
+            {
+                AnchorPreset = AnchorPresets.MiddleRight,
+                Offsets = new Margin(-width - 2 + _muteCheckbox.Offsets.Left, width, height * -0.5f, height),
+                Parent = this,
+            };
+            _picker.SelectedItemChanged += OnPickerSelectedItemChanged;
+            Height = 4 + _picker.Height;
+        }
+
+        private void OnPickerSelectedItemChanged()
+        {
+            if (Asset == (TAsset)_picker.SelectedAsset)
+                return;
+            using (new TrackUndoBlock(this))
+                Asset = (TAsset)_picker.SelectedAsset;
+        }
+
+        /// <summary>
+        /// Called when selected asset gets changed.
+        /// </summary>
+        protected virtual void OnAssetChanged()
+        {
+        }
+    }
+}