Add shared rectangle selection for all timeline tracks to select keyframes

#519

Source/Editor/GUI/CurveEditor.Base.cs

@@ -10,7 +10,7 @@ namespace FlaxEditor.GUI
     /// The base class for <see cref="CurveBase{T}"/> editors. Allows to use generic curve editor without type information at compile-time.
     /// </summary>
     [HideInEditor]
-    public abstract class CurveEditorBase : ContainerControl
+    public abstract class CurveEditorBase : ContainerControl, IKeyframesEditor
     {
         /// <summary>
         /// The UI use mode flags.
@@ -124,6 +124,11 @@ namespace FlaxEditor.GUI
         /// </summary>
         public abstract int KeyframesCount { get; }
 
+        /// <summary>
+        /// Clears the selection.
+        /// </summary>
+        public abstract void ClearSelection();
+
         /// <summary>
         /// Called when curve gets edited.
         /// </summary>
@@ -256,5 +261,20 @@ namespace FlaxEditor.GUI
                                (mode & UseMode.Vertical) == UseMode.Vertical ? value.Y : defaultValue.Y
                               );
         }
+
+        /// <inheritdoc />
+        public IKeyframesEditorContext KeyframesEditorContext { get; set; }
+
+        /// <inheritdoc />
+        public abstract void OnKeyframesDeselect(IKeyframesEditor editor);
+
+        /// <inheritdoc />
+        public abstract void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection);
+
+        /// <inheritdoc />
+        public abstract int OnKeyframesSelectionCount();
+
+        /// <inheritdoc />
+        public abstract void OnKeyframesDelete(IKeyframesEditor editor);
     }
 }

Source/Editor/GUI/CurveEditor.Contents.cs

@@ -40,7 +40,14 @@ namespace FlaxEditor.GUI
             private void UpdateSelectionRectangle()
             {
                 var selectionRect = Rectangle.FromPoints(_leftMouseDownPos, _mousePos);
+                if (_editor.KeyframesEditorContext != null)
+                    _editor.KeyframesEditorContext.OnKeyframesSelection(_editor, this, selectionRect);
+                else
+                    UpdateSelection(ref selectionRect);
+            }
 
+            internal void UpdateSelection(ref Rectangle selectionRect)
+            {
                 // Find controls to select
                 for (int i = 0; i < Children.Count; i++)
                 {
@@ -49,7 +56,6 @@ namespace FlaxEditor.GUI
                         p.IsSelected = p.Bounds.Intersects(ref selectionRect);
                     }
                 }
-
                 _editor.UpdateTangents();
             }
 
@@ -74,6 +80,21 @@ namespace FlaxEditor.GUI
             {
                 _mousePos = location;
 
+                // Start moving selection if movement started from the keyframe
+                if (_leftMouseDown && !_isMovingSelection && GetChildAt(_leftMouseDownPos) is KeyframePoint)
+                {
+                    // Start moving selected nodes
+                    _isMovingSelection = true;
+                    _movedKeyframes = false;
+                    var viewRect = _editor._mainPanel.GetClientArea();
+                    _movingSelectionStart = PointToKeyframes(location, ref viewRect);
+                    if (_movingSelectionOffsets == null || _movingSelectionOffsets.Length != _editor._points.Count)
+                        _movingSelectionOffsets = new Vector2[_editor._points.Count];
+                    for (int i = 0; i < _movingSelectionOffsets.Length; i++)
+                        _movingSelectionOffsets[i] = _editor._points[i].Point - _movingSelectionStart;
+                    _editor.OnEditingStart();
+                }
+
                 // Moving view
                 if (_rightMouseDown)
                 {
@@ -256,30 +277,32 @@ namespace FlaxEditor.GUI
                         // Check if user is pressing control
                         if (Root.GetKey(KeyboardKeys.Control))
                         {
-                            // Add to selection
+                            // Toggle selection
-                            keyframe.IsSelected = true;
+                            keyframe.IsSelected = !keyframe.IsSelected;
                             _editor.UpdateTangents();
                         }
                         // Check if node isn't selected
                         else if (!keyframe.IsSelected)
                         {
                             // Select node
-                            _editor.ClearSelection();
+                            if (_editor.KeyframesEditorContext != null)
+                                _editor.KeyframesEditorContext.OnKeyframesDeselect(_editor);
+                            else
+                                _editor.ClearSelection();
                             keyframe.IsSelected = true;
                             _editor.UpdateTangents();
                         }
-
+                        if (_editor.ShowCollapsed)
-                        // Start moving selected nodes
+                        {
+                            // Synchronize selection for curve points when collapsed so all points fo the keyframe are selected
+                            for (var i = 0; i < _editor._points.Count; i++)
+                            {
+                                var p = _editor._points[i];
+                                if (p.Index == keyframe.Index)
+                                    p.IsSelected = keyframe.IsSelected;
+                            }
+                        }
                         StartMouseCapture();
-                        _isMovingSelection = true;
-                        _movedKeyframes = false;
-                        var viewRect = _editor._mainPanel.GetClientArea();
-                        _movingSelectionStart = PointToKeyframes(location, ref viewRect);
-                        if (_movingSelectionOffsets == null || _movingSelectionOffsets.Length != _editor._points.Count)
-                            _movingSelectionOffsets = new Vector2[_editor._points.Count];
-                        for (int i = 0; i < _movingSelectionOffsets.Length; i++)
-                            _movingSelectionOffsets[i] = _editor._points[i].Point - _movingSelectionStart;
-                        _editor.OnEditingStart();
                         Focus();
                         Tooltip?.Hide();
                         return true;
@@ -306,7 +329,10 @@ namespace FlaxEditor.GUI
                     {
                         // Start selecting
                         StartMouseCapture();
-                        _editor.ClearSelection();
+                        if (_editor.KeyframesEditorContext != null)
+                            _editor.KeyframesEditorContext.OnKeyframesDeselect(_editor);
+                        else
+                            _editor.ClearSelection();
                         _editor.UpdateTangents();
                         Focus();
                         return true;
@@ -354,11 +380,6 @@ namespace FlaxEditor.GUI
                             _editor.OnEditingEnd();
                         }
                     }
-                    // Selecting
-                    else
-                    {
-                        UpdateSelectionRectangle();
-                    }
 
                     _isMovingSelection = false;
                     _isMovingTangent = false;
@@ -388,18 +409,15 @@ namespace FlaxEditor.GUI
 
                         var cm = new ContextMenu.ContextMenu();
                         cm.AddButton("Add keyframe", () => _editor.AddKeyframe(_cmShowPos)).Enabled = _editor.KeyframesCount < _editor.MaxKeyframes;
-                        if (selectionCount == 0)
+                        if (selectionCount > 0)
                         {
+                            cm.AddButton(selectionCount == 1 ? "Edit keyframe" : "Edit keyframes", () => _editor.EditKeyframes(this, location));
                         }
-                        else if (selectionCount == 1)
+                        var totalSelectionCount = _editor.KeyframesEditorContext?.OnKeyframesSelectionCount() ?? selectionCount;
+                        Debug.Log(totalSelectionCount);
+                        if (totalSelectionCount > 0)
                         {
-                            cm.AddButton("Edit keyframe", () => _editor.EditKeyframes(this, location));
+                            cm.AddButton(totalSelectionCount == 1 ? "Remove keyframe" : "Remove keyframes", _editor.RemoveKeyframes);
-                            cm.AddButton("Remove keyframe", _editor.RemoveKeyframes);
-                        }
-                        else
-                        {
-                            cm.AddButton("Edit keyframes", () => _editor.EditKeyframes(this, location));
-                            cm.AddButton("Remove keyframes", _editor.RemoveKeyframes);
                         }
                         cm.AddButton("Edit all keyframes", () => _editor.EditAllKeyframes(this, location));
                         if (_editor.EnableZoom != UseMode.Off || _editor.EnablePanning != UseMode.Off)
@@ -464,5 +482,32 @@ namespace FlaxEditor.GUI
                                   );
             }
         }
+
+        /// <inheritdoc />
+        public override void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            ClearSelection();
+        }
+
+        /// <inheritdoc />
+        public override void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (_points.Count == 0)
+                return;
+            var selectionRect = Rectangle.FromPoints(_contents.PointFromParent(control, selection.UpperLeft), _contents.PointFromParent(control, selection.BottomRight));
+            _contents.UpdateSelection(ref selectionRect);
+        }
+
+        /// <inheritdoc />
+        public override int OnKeyframesSelectionCount()
+        {
+            return SelectionCount;
+        }
+
+        /// <inheritdoc />
+        public override void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            RemoveKeyframesInner();
+        }
     }
 }

Source/Editor/GUI/CurveEditor.cs

@@ -394,7 +394,24 @@ namespace FlaxEditor.GUI
                 UpdateKeyframes();
                 UpdateTangents();
                 if (value)
+                {
+                    // Synchronize selection for curve points when collapsed so all points fo the keyframe are selected
+                    for (var i = 0; i < _points.Count; i++)
+                    {
+                        var p = _points[i];
+                        if (p.IsSelected)
+                        {
+                            for (var j = 0; j < _points.Count; j++)
+                            {
+                                var q = _points[j];
+                                if (q.Index == p.Index)
+                                    q.IsSelected = true;
+                            }
+                        }
+                    }
+
                     ShowWholeCurve();
+                }
             }
         }
 
@@ -590,6 +607,16 @@ namespace FlaxEditor.GUI
 
         private void RemoveKeyframes()
         {
+            if (KeyframesEditorContext != null)
+                KeyframesEditorContext.OnKeyframesDelete(this);
+            else
+                RemoveKeyframesInner();
+        }
+
+        private void RemoveKeyframesInner()
+        {
+            if (SelectionCount == 0)
+                return;
             var indicesToRemove = new HashSet<int>();
             for (int i = 0; i < _points.Count; i++)
             {
@@ -600,8 +627,6 @@ namespace FlaxEditor.GUI
                     indicesToRemove.Add(p.Index);
                 }
             }
-            if (indicesToRemove.Count == 0)
-                return;
 
             OnEditingStart();
             RemoveKeyframesInternal(indicesToRemove);
@@ -630,14 +655,24 @@ namespace FlaxEditor.GUI
             get
             {
                 int result = 0;
-                for (int i = 0; i < _points.Count; i++)
+                if (ShowCollapsed)
-                    if (_points[i].IsSelected)
+                {
-                        result++;
+                    for (int i = 0; i < _points.Count; i++)
+                        if (_points[i].Component == 0 && _points[i].IsSelected)
+                            result++;
+                }
+                else
+                {
+                    for (int i = 0; i < _points.Count; i++)
+                        if (_points[i].IsSelected)
+                            result++;
+                }
                 return result;
             }
         }
 
-        private void ClearSelection()
+        /// <inheritdoc />
+        public override void ClearSelection()
         {
             for (int i = 0; i < _points.Count; i++)
             {
@@ -645,7 +680,10 @@ namespace FlaxEditor.GUI
             }
         }
 
-        private void SelectAll()
+        /// <summary>
+        /// Selects all keyframes.
+        /// </summary>
+        public void SelectAll()
         {
             for (int i = 0; i < _points.Count; i++)
             {
@@ -888,6 +926,7 @@ namespace FlaxEditor.GUI
             TickSteps = null;
             _tickStrengths = null;
             KeyframesChanged = null;
+            KeyframesEditorContext = null;
 
             base.OnDestroy();
         }

Source/Editor/GUI/IKeyframesEditor.cs

@@ -0,0 +1,44 @@
+// Copyright (c) 2012-2021 Wojciech Figat. All rights reserved.
+
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.GUI
+{
+    /// <summary>
+    /// Interface for keyframes/curves editors.
+    /// </summary>
+    public interface IKeyframesEditor
+    {
+        /// <summary>
+        /// Gets or sets the keyframes editor collection used by this editor.
+        /// </summary>
+        IKeyframesEditorContext KeyframesEditorContext { get; set; }
+
+        /// <summary>
+        /// Called when keyframes selection should be cleared for editor.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        void OnKeyframesDeselect(IKeyframesEditor editor);
+
+        /// <summary>
+        /// Called when keyframes selection rectangle gets updated.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        /// <param name="control">The source selection control.</param>
+        /// <param name="selection">The source selection rectangle (in source control local space).</param>
+        void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection);
+
+        /// <summary>
+        /// Called to calculate the total amount of selected keyframes in the editor.
+        /// </summary>
+        /// <returns>The selected keyframes amount.</returns>
+        int OnKeyframesSelectionCount();
+
+        /// <summary>
+        /// Called when keyframes selection should be deleted for all editors.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        void OnKeyframesDelete(IKeyframesEditor editor);
+    }
+}

Source/Editor/GUI/IKeyframesEditorContext.cs

@@ -0,0 +1,39 @@
+// Copyright (c) 2012-2021 Wojciech Figat. All rights reserved.
+
+using FlaxEngine;
+using FlaxEngine.GUI;
+
+namespace FlaxEditor.GUI
+{
+    /// <summary>
+    /// Interface for context for collection of <see cref="IKeyframesEditor"/>.
+    /// </summary>
+    public interface IKeyframesEditorContext
+    {
+        /// <summary>
+        /// Called when keyframes selection should be cleared for all editors.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        void OnKeyframesDeselect(IKeyframesEditor editor);
+
+        /// <summary>
+        /// Called when keyframes selection rectangle gets updated.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        /// <param name="control">The source selection control.</param>
+        /// <param name="selection">The source selection rectangle (in source control local space).</param>
+        void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection);
+
+        /// <summary>
+        /// Called to calculate the total amount of selected keyframes in the editor.
+        /// </summary>
+        /// <returns>The selected keyframes amount.</returns>
+        int OnKeyframesSelectionCount();
+
+        /// <summary>
+        /// Called when keyframes selection should be deleted for all editors.
+        /// </summary>
+        /// <param name="editor">The source editor.</param>
+        void OnKeyframesDelete(IKeyframesEditor editor);
+    }
+}

Source/Editor/GUI/Timeline/GUI/KeyframesEditor.cs

@@ -15,7 +15,7 @@ namespace FlaxEditor.GUI
     /// </summary>
     /// <seealso cref="FlaxEngine.GUI.ContainerControl" />
     [HideInEditor]
-    public class KeyframesEditor : ContainerControl
+    public class KeyframesEditor : ContainerControl, IKeyframesEditor
     {
         /// <summary>
         /// A single keyframe.
@@ -91,7 +91,14 @@ namespace FlaxEditor.GUI
             private void UpdateSelectionRectangle()
             {
                 var selectionRect = Rectangle.FromPoints(_leftMouseDownPos, _mousePos);
+                if (_editor.KeyframesEditorContext != null)
+                    _editor.KeyframesEditorContext.OnKeyframesSelection(_editor, this, selectionRect);
+                else
+                    UpdateSelection(ref selectionRect);
+            }
 
+            internal void UpdateSelection(ref Rectangle selectionRect)
+            {
                 // Find controls to select
                 for (int i = 0; i < Children.Count; i++)
                 {
@@ -123,6 +130,21 @@ namespace FlaxEditor.GUI
             {
                 _mousePos = location;
 
+                // Start moving selection if movement started from the keyframe
+                if (_leftMouseDown && !_isMovingSelection && GetChildAt(_leftMouseDownPos) is KeyframePoint)
+                {
+                    // Start moving selected nodes
+                    _isMovingSelection = true;
+                    _movedKeyframes = false;
+                    var viewRect = _editor._mainPanel.GetClientArea();
+                    _movingSelectionStart = PointToKeyframes(location, ref viewRect).X;
+                    if (_movingSelectionOffsets == null || _movingSelectionOffsets.Length != _editor._keyframes.Count)
+                        _movingSelectionOffsets = new float[_editor._keyframes.Count];
+                    for (int i = 0; i < _movingSelectionOffsets.Length; i++)
+                        _movingSelectionOffsets[i] = _editor._keyframes[i].Time - _movingSelectionStart;
+                    _editor.OnEditingStart();
+                }
+
                 // Moving view
                 if (_rightMouseDown)
                 {
@@ -248,28 +270,20 @@ namespace FlaxEditor.GUI
                         // Check if user is pressing control
                         if (Root.GetKey(KeyboardKeys.Control))
                         {
-                            // Add to selection
+                            // Toggle selection
-                            keyframe.Select();
+                            keyframe.IsSelected = !keyframe.IsSelected;
                         }
                         // Check if node isn't selected
                         else if (!keyframe.IsSelected)
                         {
                             // Select node
-                            _editor.ClearSelection();
+                            if (_editor.KeyframesEditorContext != null)
-                            keyframe.Select();
+                                _editor.KeyframesEditorContext.OnKeyframesDeselect(_editor);
+                            else
+                                _editor.ClearSelection();
+                            keyframe.IsSelected = true;
                         }
-
-                        // Start moving selected nodes
                         StartMouseCapture();
-                        _isMovingSelection = true;
-                        _movedKeyframes = false;
-                        var viewRect = _editor._mainPanel.GetClientArea();
-                        _movingSelectionStart = PointToKeyframes(location, ref viewRect).X;
-                        if (_movingSelectionOffsets == null || _movingSelectionOffsets.Length != _editor._keyframes.Count)
-                            _movingSelectionOffsets = new float[_editor._keyframes.Count];
-                        for (int i = 0; i < _movingSelectionOffsets.Length; i++)
-                            _movingSelectionOffsets[i] = _editor._keyframes[i].Time - _movingSelectionStart;
-                        _editor.OnEditingStart();
                         Focus();
                         Tooltip?.Hide();
                         return true;
@@ -281,7 +295,10 @@ namespace FlaxEditor.GUI
                     {
                         // Start selecting
                         StartMouseCapture();
-                        _editor.ClearSelection();
+                        if (_editor.KeyframesEditorContext != null)
+                            _editor.KeyframesEditorContext.OnKeyframesDeselect(_editor);
+                        else
+                            _editor.ClearSelection();
                         Focus();
                         return true;
                     }
@@ -319,11 +336,6 @@ namespace FlaxEditor.GUI
                             _editor.UpdateKeyframes();
                         }
                     }
-                    // Selecting
-                    else
-                    {
-                        UpdateSelectionRectangle();
-                    }
 
                     _isMovingSelection = false;
                     _movedKeyframes = false;
@@ -343,7 +355,7 @@ namespace FlaxEditor.GUI
                         {
                             // Select node
                             selectionCount = 1;
-                            point.Select();
+                            point.IsSelected = true;
                         }
 
                         var viewRect = _editor._mainPanel.GetClientArea();
@@ -351,18 +363,15 @@ namespace FlaxEditor.GUI
 
                         var cm = new ContextMenu.ContextMenu();
                         cm.AddButton("Add keyframe", () => _editor.AddKeyframe(_cmShowPos)).Enabled = _editor.Keyframes.Count < _editor.MaxKeyframes;
-                        if (selectionCount == 0)
+                        if (selectionCount > 0)
                         {
+                            cm.AddButton(selectionCount == 1 ? "Edit keyframe" : "Edit keyframes", () => _editor.EditKeyframes(this, location));
                         }
-                        else if (selectionCount == 1)
+                        var totalSelectionCount = _editor.KeyframesEditorContext?.OnKeyframesSelectionCount() ?? selectionCount;
+                        Debug.Log(totalSelectionCount);
+                        if (totalSelectionCount > 0)
                         {
-                            cm.AddButton("Edit keyframe", () => _editor.EditKeyframes(this, location));
+                            cm.AddButton(totalSelectionCount == 1 ? "Remove keyframe" : "Remove keyframes", _editor.RemoveKeyframes);
-                            cm.AddButton("Remove keyframe", _editor.RemoveKeyframes);
-                        }
-                        else
-                        {
-                            cm.AddButton("Edit keyframes", () => _editor.EditKeyframes(this, location));
-                            cm.AddButton("Remove keyframes", _editor.RemoveKeyframes);
                         }
                         cm.AddButton("Edit all keyframes", () => _editor.EditAllKeyframes(this, location));
                         if (_editor.EnableZoom && _editor.EnablePanning)
@@ -482,16 +491,6 @@ namespace FlaxEditor.GUI
                 return false;
             }
 
-            public void Select()
-            {
-                IsSelected = true;
-            }
-
-            public void Deselect()
-            {
-                IsSelected = false;
-            }
-
             /// <summary>
             /// Updates the tooltip.
             /// </summary>
@@ -980,7 +979,16 @@ namespace FlaxEditor.GUI
 
         private void RemoveKeyframes()
         {
-            bool edited = false;
+            if (KeyframesEditorContext != null)
+                KeyframesEditorContext.OnKeyframesDelete(this);
+            else
+                RemoveKeyframesInner();
+        }
+
+        private void RemoveKeyframesInner()
+        {
+            if (SelectionCount == 0)
+                return;
             var keyframes = new Dictionary<int, Keyframe>(_keyframes.Count);
             for (int i = 0; i < _points.Count; i++)
             {
@@ -991,12 +999,9 @@ namespace FlaxEditor.GUI
                 }
                 else
                 {
-                    p.Deselect();
+                    p.IsSelected = false;
-                    edited = true;
                 }
             }
-            if (!edited)
-                return;
 
             OnEditingStart();
             _keyframes.Clear();
@@ -1088,19 +1093,25 @@ namespace FlaxEditor.GUI
             }
         }
 
-        private void ClearSelection()
+        /// <summary>
+        /// Clears the selection.
+        /// </summary>
+        public void ClearSelection()
         {
             for (int i = 0; i < _points.Count; i++)
             {
-                _points[i].Deselect();
+                _points[i].IsSelected = false;
             }
         }
 
-        private void SelectAll()
+        /// <summary>
+        /// Selects all keyframes.
+        /// </summary>
+        public void SelectAll()
         {
             for (int i = 0; i < _points.Count; i++)
             {
-                _points[i].Select();
+                _points[i].IsSelected = true;
             }
         }
 
@@ -1182,8 +1193,39 @@ namespace FlaxEditor.GUI
             // Cleanup
             _points.Clear();
             _keyframes.Clear();
+            KeyframesEditorContext = null;
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public IKeyframesEditorContext KeyframesEditorContext { get; set; }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            ClearSelection();
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (_keyframes.Count == 0)
+                return;
+            var selectionRect = Rectangle.FromPoints(_contents.PointFromParent(control, selection.UpperLeft), _contents.PointFromParent(control, selection.BottomRight));
+            _contents.UpdateSelection(ref selectionRect);
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            return SelectionCount;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            RemoveKeyframesInner();
+        }
     }
 }

Source/Editor/GUI/Timeline/Timeline.cs

@@ -21,7 +21,7 @@ namespace FlaxEditor.GUI.Timeline
     /// </summary>
     /// <seealso cref="FlaxEngine.GUI.ContainerControl" />
     [HideInEditor]
-    public class Timeline : ContainerControl
+    public class Timeline : ContainerControl, IKeyframesEditorContext
     {
         private static readonly KeyValuePair<float, string>[] FPSValues =
         {
@@ -2393,5 +2393,49 @@ namespace FlaxEditor.GUI.Timeline
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            for (int i = 0; i < _tracks.Count; i++)
+            {
+                if (_tracks[i] is IKeyframesEditorContext trackContext)
+                    trackContext.OnKeyframesDeselect(editor);
+            }
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            var globalControl = _backgroundArea;
+            var globalRect = Rectangle.FromPoints(control.PointToParent(globalControl, selection.UpperLeft), control.PointToParent(globalControl, selection.BottomRight));
+            for (int i = 0; i < _tracks.Count; i++)
+            {
+                if (_tracks[i] is IKeyframesEditorContext trackContext)
+                    trackContext.OnKeyframesSelection(editor, globalControl, globalRect);
+            }
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            int result = 0;
+            for (int i = 0; i < _tracks.Count; i++)
+            {
+                if (_tracks[i] is IKeyframesEditorContext trackContext)
+                    result += trackContext.OnKeyframesSelectionCount();
+            }
+            return result;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            for (int i = 0; i < _tracks.Count; i++)
+            {
+                if (_tracks[i] is IKeyframesEditorContext trackContext)
+                    trackContext.OnKeyframesDelete(editor);
+            }
+        }
     }
 }

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

@@ -225,7 +225,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
     /// The child volume track for audio track. Used to animate audio volume over time.
     /// </summary>
     /// <seealso cref="FlaxEditor.GUI.Timeline.Track" />
-    class AudioVolumeTrack : Track
+    class AudioVolumeTrack : Track, IKeyframesEditorContext
     {
         /// <summary>
         /// Gets the archetype.
@@ -478,7 +478,11 @@ namespace FlaxEditor.GUI.Timeline.Tracks
                 return;
             Curve.Visible = Visible;
             if (!Visible)
+            {
+                Curve.ClearSelection();
                 return;
+            }
+            Curve.KeyframesEditorContext = Timeline;
             Curve.CustomViewPanning = Timeline.OnKeyframesViewPanning;
             Curve.Bounds = new Rectangle(_audioMedia.X, Y + 1.0f, _audioMedia.Width, Height - 2.0f);
 
@@ -639,5 +643,32 @@ namespace FlaxEditor.GUI.Timeline.Tracks
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesDeselect(editor);
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesSelection(editor, control, selection);
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            return Curve != null && Curve.Visible ? Curve.OnKeyframesSelectionCount() : 0;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesDelete(editor);
+        }
     }
 }

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

@@ -15,7 +15,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
     /// The timeline track for animating object property via Curve.
     /// </summary>
     /// <seealso cref="MemberTrack" />
-    public abstract class CurvePropertyTrackBase : MemberTrack
+    public abstract class CurvePropertyTrackBase : MemberTrack, IKeyframesEditorContext
     {
         private sealed class Splitter : Control
         {
@@ -226,8 +226,12 @@ namespace FlaxEditor.GUI.Timeline.Tracks
                 return;
             Curve.Visible = Visible;
             if (!Visible)
+            {
+                Curve.ClearSelection();
                 return;
+            }
             var expanded = IsExpanded;
+            Curve.KeyframesEditorContext = Timeline;
             Curve.CustomViewPanning = Timeline.OnKeyframesViewPanning;
             Curve.Bounds = new Rectangle(Timeline.StartOffset, Y + 1.0f, Timeline.Duration * Timeline.UnitsPerSecond * Timeline.Zoom, Height - 2.0f);
             Curve.ViewScale = new Vector2(Timeline.Zoom, Curve.ViewScale.Y);
@@ -240,11 +244,13 @@ namespace FlaxEditor.GUI.Timeline.Tracks
             if (expanded)
             {
                 if (_splitter == null)
+                {
                     _splitter = new Splitter
                     {
                         _track = this,
                         Parent = Curve,
                     };
+                }
                 var splitterHeight = 4.0f;
                 _splitter.Bounds = new Rectangle(0, Curve.Height - splitterHeight, Curve.Width, splitterHeight);
             }
@@ -424,6 +430,33 @@ namespace FlaxEditor.GUI.Timeline.Tracks
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesDeselect(editor);
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesSelection(editor, control, selection);
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            return Curve != null && Curve.Visible ? Curve.OnKeyframesSelectionCount() : 0;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            if (Curve != null && Curve.Visible)
+                Curve.OnKeyframesDelete(editor);
+        }
     }
 
     /// <summary>

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

@@ -16,7 +16,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
     /// The timeline track for invoking events on a certain points in the time.
     /// </summary>
     /// <seealso cref="MemberTrack" />
-    public class EventTrack : MemberTrack
+    public class EventTrack : MemberTrack, IKeyframesEditorContext
     {
         /// <summary>
         /// Gets the archetype.
@@ -285,7 +285,11 @@ namespace FlaxEditor.GUI.Timeline.Tracks
                 return;
             Events.Visible = Visible;
             if (!Visible)
+            {
+                Events.ClearSelection();
                 return;
+            }
+            Events.KeyframesEditorContext = Timeline;
             Events.CustomViewPanning = Timeline.OnKeyframesViewPanning;
             Events.Bounds = new Rectangle(Timeline.StartOffset, Y + 1.0f, Timeline.Duration * Timeline.UnitsPerSecond * Timeline.Zoom, Height - 2.0f);
             Events.ViewScale = new Vector2(Timeline.Zoom, 1.0f);
@@ -407,5 +411,32 @@ namespace FlaxEditor.GUI.Timeline.Tracks
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            if (Events != null && Events.Visible)
+                Events.OnKeyframesDeselect(editor);
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (Events != null && Events.Visible)
+                Events.OnKeyframesSelection(editor, control, selection);
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            return Events != null && Events.Visible ? Events.OnKeyframesSelectionCount() : 0;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            if (Events != null && Events.Visible)
+                Events.OnKeyframesDelete(editor);
+        }
     }
 }

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

@@ -15,7 +15,7 @@ namespace FlaxEditor.GUI.Timeline.Tracks
     /// The timeline track for animating object property via keyframes collection.
     /// </summary>
     /// <seealso cref="MemberTrack" />
-    public class KeyframesPropertyTrack : MemberTrack
+    public class KeyframesPropertyTrack : MemberTrack, IKeyframesEditorContext
     {
         /// <summary>
         /// Gets the archetype.
@@ -252,7 +252,11 @@ namespace FlaxEditor.GUI.Timeline.Tracks
                 return;
             Keyframes.Visible = Visible;
             if (!Visible)
+            {
+                Keyframes.ClearSelection();
                 return;
+            }
+            Keyframes.KeyframesEditorContext = Timeline;
             Keyframes.CustomViewPanning = Timeline.OnKeyframesViewPanning;
             Keyframes.Bounds = new Rectangle(Timeline.StartOffset, Y + 1.0f, Timeline.Duration * Timeline.UnitsPerSecond * Timeline.Zoom, Height - 2.0f);
             Keyframes.ViewScale = new Vector2(Timeline.Zoom, 1.0f);
@@ -387,5 +391,32 @@ namespace FlaxEditor.GUI.Timeline.Tracks
 
             base.OnDestroy();
         }
+
+        /// <inheritdoc />
+        public void OnKeyframesDeselect(IKeyframesEditor editor)
+        {
+            if (Keyframes != null && Keyframes.Visible)
+                Keyframes.OnKeyframesDeselect(editor);
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesSelection(IKeyframesEditor editor, ContainerControl control, Rectangle selection)
+        {
+            if (Keyframes != null && Keyframes.Visible)
+                Keyframes.OnKeyframesSelection(editor, control, selection);
+        }
+
+        /// <inheritdoc />
+        public int OnKeyframesSelectionCount()
+        {
+            return Keyframes != null && Keyframes.Visible ? Keyframes.OnKeyframesSelectionCount() : 0;
+        }
+
+        /// <inheritdoc />
+        public void OnKeyframesDelete(IKeyframesEditor editor)
+        {
+            if (Keyframes != null && Keyframes.Visible)
+                Keyframes.OnKeyframesDelete(editor);
+        }
     }
 }