Add option to delete media from Timeline

#519

Source/Editor/GUI/Timeline/Media.cs

@@ -185,6 +185,11 @@ namespace FlaxEditor.GUI.Timeline
         /// </summary>
         public bool CanSplit;
 
+        /// <summary>
+        /// Gets a value indicating whether this media can be removed.
+        /// </summary>
+        public bool CanDelete;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Media"/> class.
         /// </summary>
@@ -200,6 +205,8 @@ namespace FlaxEditor.GUI.Timeline
         /// <param name="controlUnderMouse">The found control under the mouse cursor.</param>
         public virtual void OnTimelineShowContextMenu(ContextMenu.ContextMenu menu, Control controlUnderMouse)
         {
+            if (CanDelete && Track.Media.Count > Track.MinMediaCount)
+                menu.AddButton("Delete media", Delete);
         }
 
         /// <summary>
@@ -284,6 +291,14 @@ namespace FlaxEditor.GUI.Timeline
             return clone;
         }
 
+        /// <summary>
+        /// Deletes this media.
+        /// </summary>
+        public void Delete()
+        {
+            _timeline.Delete(this);
+        }
+
         /// <inheritdoc />
         public override void GetDesireClientArea(out Rectangle rect)
         {

Source/Editor/GUI/Timeline/Timeline.cs

@@ -1451,7 +1451,7 @@ namespace FlaxEditor.GUI.Timeline
         }
 
         /// <summary>
-        /// Deletes the tracks.
+        /// Deletes the track.
         /// </summary>
         /// <param name="track">The track to delete (and its sub tracks).</param>
         /// <param name="withUndo">True if use undo/redo action for track removing.</param>
@@ -1459,8 +1459,6 @@ namespace FlaxEditor.GUI.Timeline
         {
             if (track == null)
                 throw new ArgumentNullException();
-
-            // Delete tracks
             var tracks = new List<Track>(4);
             GetTracks(track, tracks);
             if (withUndo && Undo != null && Undo.Enabled)
@@ -1497,6 +1495,43 @@ namespace FlaxEditor.GUI.Timeline
             track.OnDeleted();
         }
 
+        /// <summary>
+        /// Deletes the media.
+        /// </summary>
+        /// <param name="media">The media to delete.</param>
+        /// <param name="withUndo">True if use undo/redo action for media removing.</param>
+        public void Delete(Media media, bool withUndo = true)
+        {
+            if (media == null)
+                throw new ArgumentNullException();
+            var track = media.Track;
+            if (track == null)
+                throw new InvalidOperationException();
+            if (withUndo && Undo != null && Undo.Enabled)
+            {
+                var before = EditTrackAction.CaptureData(track);
+                OnDeleteMedia(media);
+                var after = EditTrackAction.CaptureData(track);
+                Undo.AddAction(new EditTrackAction(this, track, before, after));
+            }
+            else
+            {
+                OnDeleteMedia(media);
+            }
+            MarkAsEdited();
+        }
+
+        /// <summary>
+        /// Called to delete media.
+        /// </summary>
+        /// <param name="media">The media.</param>
+        protected virtual void OnDeleteMedia(Media media)
+        {
+            SelectedMedia.Remove(media);
+            media.Track.RemoveMedia(media);
+            media.OnDeleted();
+        }
+
         /// <summary>
         /// Duplicates the selected tracks/media events.
         /// </summary>

Source/Editor/GUI/Timeline/Track.cs

@@ -1032,10 +1032,10 @@ namespace FlaxEditor.GUI.Timeline
                 // Show context menu
                 var menu = new ContextMenu.ContextMenu();
                 if (CanRename)
-                    menu.AddButton("Rename", StartRenaming);
+                    menu.AddButton("Rename", "F2", StartRenaming);
                 if (CanCopyPaste)
-                    menu.AddButton("Duplicate", () => Timeline.DuplicateSelection());
-                menu.AddButton("Delete", Delete);
+                    menu.AddButton("Duplicate", "Ctrl+D", () => Timeline.DuplicateSelection());
+                menu.AddButton("Delete", "Del", Delete);
                 if (CanExpand)
                 {
                     menu.AddSeparator();

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

@@ -88,6 +88,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
         public AudioMedia()
         {
             CanSplit = true;
+            CanDelete = true;
             Preview = new AudioClipPreview
             {
                 AnchorPreset = AnchorPresets.StretchAll,

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

@@ -35,6 +35,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
         {
             ClipChildren = true;
             CanSplit = true;
+            CanDelete = true;
         }
 
         /// <summary>
@@ -325,10 +326,10 @@ namespace FlaxEditor.GUI.Timeline.Tracks
         /// <inheritdoc />
         public override void OnTimelineShowContextMenu(ContextMenu.ContextMenu menu, Control controlUnderMouse)
         {
-            base.OnTimelineShowContextMenu(menu, controlUnderMouse);
-
             if (((CameraCutTrack)Track).Camera)
                 menu.AddButton("Refresh thumbnails", () => UpdateThumbnails());
+
+            base.OnTimelineShowContextMenu(menu, controlUnderMouse);
         }
 
         /// <inheritdoc />

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

@@ -36,6 +36,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
         public PostProcessMaterialMedia()
         {
             CanSplit = true;
+            CanDelete = true;
         }
 
         /// <inheritdoc />