Merge branch 'add-xmlnsprefix' of https://github.com/bmello4688/Avalonia into add-xmlnsprefix

samples/BindingDemo/App.xaml.cs

@@ -26,6 +26,6 @@ namespace BindingDemo
           => AppBuilder.Configure<App>()
                 .UsePlatformDetect()
                 .UseReactiveUI()
-                .LogToDebug();
+                .LogToTrace();
     }
 }

samples/ControlCatalog.Desktop/Program.cs

@@ -18,7 +18,7 @@ namespace ControlCatalog
         /// </summary>
         public static AppBuilder BuildAvaloniaApp()
             => AppBuilder.Configure<App>()
-                .LogToDebug()
+                .LogToTrace()
                 .UsePlatformDetect()
                 .UseReactiveUI();
 

samples/ControlCatalog.NetCore/Program.cs

@@ -121,7 +121,7 @@ namespace ControlCatalog.NetCore
                 .UseSkia()
                 .UseReactiveUI()
                 .UseManagedSystemDialogs()
-                .LogToDebug();
+                .LogToTrace();
 
         static void SilenceConsole()
         {

samples/RenderDemo/App.xaml.cs

@@ -33,6 +33,6 @@ namespace RenderDemo
                })
                 .UsePlatformDetect()
                 .UseReactiveUI()
-                .LogToDebug();
+                .LogToTrace();
     }
 }

samples/Sandbox/Program.cs

@@ -10,7 +10,7 @@ namespace Sandbox
             AppBuilder.Configure<App>()
                 .UsePlatformDetect()
                 .UseReactiveUI()
-                .LogToDebug()
+                .LogToTrace()
                 .StartWithClassicDesktopLifetime(args);
         }
     }

samples/VirtualizationDemo/Program.cs

@@ -9,7 +9,7 @@ namespace VirtualizationDemo
             => AppBuilder.Configure<App>()
                 .UsePlatformDetect()
                 .UseReactiveUI()
-                .LogToDebug();
+                .LogToTrace();
 
         public static int Main(string[] args)
             => BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);

src/Avalonia.Base/ApiCompatBaseline.txt

@@ -1,3 +1,4 @@
 Compat issues with assembly Avalonia.Base:
 CannotAddAbstractMembers : Member 'protected System.IObservable<Avalonia.AvaloniaPropertyChangedEventArgs> Avalonia.AvaloniaProperty.GetChanged()' is abstract in the implementation but is missing in the contract.
-Total Issues: 1
+TypesMustExist : Type 'Avalonia.Logging.DebugLogSink' does not exist in the implementation but it does exist in the contract.
+Total Issues: 2

src/Avalonia.Base/Logging/DebugLogSink.cs → src/Avalonia.Base/Logging/TraceLogSink.cs

@@ -6,12 +6,12 @@ using Avalonia.Utilities;
 
 namespace Avalonia.Logging
 {
-    public class DebugLogSink : ILogSink
+    public class TraceLogSink : ILogSink
     {
         private readonly LogEventLevel _level;
         private readonly IList<string> _areas;
 
-        public DebugLogSink(
+        public TraceLogSink(
             LogEventLevel minimumLevel,
             IList<string> areas = null)
         {
@@ -28,7 +28,7 @@ namespace Avalonia.Logging
         {
             if (IsEnabled(level, area))
             {
-                Debug.WriteLine(Format<object, object, object>(area, messageTemplate, source));
+                Trace.WriteLine(Format<object, object, object>(area, messageTemplate, source));
             }
         }
 
@@ -36,7 +36,7 @@ namespace Avalonia.Logging
         {
             if (IsEnabled(level, area))
             {
-                Debug.WriteLine(Format<T0, object, object>(area, messageTemplate, source, propertyValue0));
+                Trace.WriteLine(Format<T0, object, object>(area, messageTemplate, source, propertyValue0));
             }
         }
 
@@ -44,7 +44,7 @@ namespace Avalonia.Logging
         {
             if (IsEnabled(level, area))
             {
-                Debug.WriteLine(Format<T0, T1, object>(area, messageTemplate, source, propertyValue0, propertyValue1));
+                Trace.WriteLine(Format<T0, T1, object>(area, messageTemplate, source, propertyValue0, propertyValue1));
             }
         }
 
@@ -52,7 +52,7 @@ namespace Avalonia.Logging
         {
             if (IsEnabled(level, area))
             {
-                Debug.WriteLine(Format(area, messageTemplate, source, propertyValue0, propertyValue1, propertyValue2));
+                Trace.WriteLine(Format(area, messageTemplate, source, propertyValue0, propertyValue1, propertyValue2));
             }
         }
 
@@ -60,7 +60,7 @@ namespace Avalonia.Logging
         {
             if (IsEnabled(level, area))
             {
-                Debug.WriteLine(Format(area, messageTemplate, source, propertyValues));
+                Trace.WriteLine(Format(area, messageTemplate, source, propertyValues));
             }
         }
 

src/Avalonia.Controls.DataGrid/DataGridColumnHeader.cs

@@ -340,8 +340,6 @@ namespace Avalonia.Controls
 
             if (OwningGrid != null && OwningGrid.ColumnHeaders != null)
             {
-                args.Pointer.Capture(this);
-
                 _dragMode = DragMode.MouseDown;
                 _frozenColumnsWidth = OwningGrid.ColumnsInternal.GetVisibleFrozenEdgedColumnsWidth();
                 _lastMousePositionHeaders = this.Translate(OwningGrid.ColumnHeaders, mousePosition);
@@ -413,8 +411,9 @@ namespace Avalonia.Controls
         }
 
         //TODO DragEvents
-        internal void OnMouseMove(ref bool handled, Point mousePosition, Point mousePositionHeaders)
+        internal void OnMouseMove(PointerEventArgs args, Point mousePosition, Point mousePositionHeaders)
         {
+            var handled = args.Handled;
             if (handled || OwningGrid == null || OwningGrid.ColumnHeaders == null)
             {
                 return;
@@ -438,7 +437,10 @@ namespace Avalonia.Controls
             }
 
             _lastMousePositionHeaders = mousePositionHeaders;
-
+            
+            if (args.Pointer.Captured != this)
+                args.Pointer.Capture(this);
+            
             SetDragCursor(mousePosition);
         }
 
@@ -506,8 +508,7 @@ namespace Avalonia.Controls
             Point mousePosition = e.GetPosition(this);
             Point mousePositionHeaders = e.GetPosition(OwningGrid.ColumnHeaders);
 
-            bool handled = false;
+            OnMouseMove(e, mousePosition, mousePositionHeaders);
-            OnMouseMove(ref handled, mousePosition, mousePositionHeaders);
         }
 
         /// <summary>

src/Avalonia.Controls/ContextMenu.cs

@@ -62,6 +62,12 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<Rect?> PlacementRectProperty =
             AvaloniaProperty.Register<Popup, Rect?>(nameof(PlacementRect));
 
+        /// <summary>
+        /// Defines the <see cref="WindowManagerAddShadowHint"/> property.
+        /// </summary>
+        public static readonly StyledProperty<bool> WindowManagerAddShadowHintProperty  =
+            Popup.WindowManagerAddShadowHintProperty.AddOwner<ContextMenu>();
+
         /// <summary>
         /// Defines the <see cref="PlacementTarget"/> property.
         /// </summary>
@@ -158,6 +164,12 @@ namespace Avalonia.Controls
             set { SetValue(PlacementModeProperty, value); }
         }
 
+        public bool WindowManagerAddShadowHint
+        {
+            get { return GetValue(WindowManagerAddShadowHintProperty); }
+            set { SetValue(WindowManagerAddShadowHintProperty, value); }
+        }
+
         /// <summary>
         /// Gets or sets the the anchor rectangle within the parent that the context menu will be placed
         /// relative to when <see cref="PlacementMode"/> is <see cref="PlacementMode.AnchorAndGravity"/>.
@@ -267,6 +279,7 @@ namespace Avalonia.Controls
                     PlacementTarget = PlacementTarget ?? control,
                     IsLightDismissEnabled = true,
                     OverlayDismissEventPassThrough = true,
+                    WindowManagerAddShadowHint = WindowManagerAddShadowHint,
                 };
 
                 _popup.Opened += PopupOpened;

src/Avalonia.Controls/ItemsControl.cs

@@ -169,7 +169,7 @@ namespace Avalonia.Controls
         /// </summary>
         /// <param name="items">The collection.</param>
         /// <param name="index">The index.</param>
-        /// <returns>The index of the item or -1 if the item was not found.</returns>
+        /// <returns>The item at the given index or null if the index is out of bounds.</returns>
         protected static object ElementAt(IEnumerable items, int index)
         {
             if (index != -1 && index < items.Count())

src/Avalonia.Controls/LoggingExtensions.cs

@@ -1,25 +1,36 @@
-using Avalonia.Controls;
+using System;
+using Avalonia.Controls;
 using Avalonia.Logging;
 
 namespace Avalonia
 {
     public static class LoggingExtensions
     {
+        [Obsolete("Use LogToTrace")]
+        public static T LogToDebug<T>(
+            this T builder,
+            LogEventLevel level = LogEventLevel.Warning,
+            params string[] areas)
+                where T : AppBuilderBase<T>, new()
+        {
+            return LogToTrace(builder, level, areas);
+        }
+
         /// <summary>
-        /// Logs Avalonia events to the <see cref="System.Diagnostics.Debug"/> sink.
+        /// Logs Avalonia events to the <see cref="System.Diagnostics.Trace"/> sink.
         /// </summary>
         /// <typeparam name="T">The application class type.</typeparam>
         /// <param name="builder">The app builder instance.</param>
         /// <param name="level">The minimum level to log.</param>
         /// <param name="areas">The areas to log. Valid values are listed in <see cref="LogArea"/>.</param>
         /// <returns>The app builder instance.</returns>
-        public static T LogToDebug<T>(
+        public static T LogToTrace<T>(
             this T builder,
             LogEventLevel level = LogEventLevel.Warning,
             params string[] areas)
                 where T : AppBuilderBase<T>, new()
         {
-            Logger.Sink = new DebugLogSink(level, areas);
+            Logger.Sink = new TraceLogSink(level, areas);
             return builder;
         }
     }

src/Avalonia.Controls/Presenters/ItemVirtualizerSimple.cs

@@ -512,6 +512,13 @@ namespace Avalonia.Controls.Presenters
             var generator = Owner.ItemContainerGenerator;
             var newOffset = -1.0;
 
+            //better not trigger any container generation/recycle while  or layout stuff
+            //before panel is attached/visible
+            if (!panel.IsAttachedToVisualTree)
+            {
+                return null;
+            }
+
             if (!panel.IsMeasureValid && panel.PreviousMeasure.HasValue)
             {
                 //before any kind of scrolling we need to make sure panel measure is valid

src/Avalonia.Controls/Primitives/VisualLayerManager.cs

@@ -67,8 +67,6 @@ namespace Avalonia.Controls.Primitives
         {
             get
             {
-                if (IsPopup)
-                    return null;
                 var rv = FindLayer<LightDismissOverlayLayer>();
                 if (rv == null)
                 {

src/Avalonia.Input/MouseDevice.cs

@@ -19,6 +19,7 @@ namespace Avalonia.Input
 
         private readonly Pointer _pointer;
         private bool _disposed;
+        private PixelPoint? _position; 
 
         public MouseDevice(Pointer? pointer = null)
         {
@@ -39,10 +40,11 @@ namespace Avalonia.Input
         /// <summary>
         /// Gets the mouse position, in screen coordinates.
         /// </summary>
+        [Obsolete("Use events instead")]
         public PixelPoint Position
         {
-            get;
+            get => _position ?? new PixelPoint(-1, -1);
-            protected set;
+            protected set => _position = value;
         }
 
         /// <summary>
@@ -91,7 +93,16 @@ namespace Avalonia.Input
 
         public void SceneInvalidated(IInputRoot root, Rect rect)
         {
-            var clientPoint = root.PointToClient(Position);
+            // Pointer is outside of the target area
+            if (_position == null )
+            {
+                if (root.PointerOverElement != null)
+                    ClearPointerOver(this, 0, root, PointerPointProperties.None, KeyModifiers.None);
+                return;
+            }
+            
+            
+            var clientPoint = root.PointToClient(_position.Value);
 
             if (rect.Contains(clientPoint))
             {
@@ -132,7 +143,7 @@ namespace Avalonia.Input
             if(mouse._disposed)
                 return;
 
-            Position = e.Root.PointToScreen(e.Position);
+            _position = e.Root.PointToScreen(e.Position);
             var props = CreateProperties(e);
             var keyModifiers = KeyModifiersUtils.ConvertToKey(e.InputModifiers);
             switch (e.Type)
@@ -176,6 +187,7 @@ namespace Avalonia.Input
             device = device ?? throw new ArgumentNullException(nameof(device));
             root = root ?? throw new ArgumentNullException(nameof(root));
 
+            _position = null;
             ClearPointerOver(this, timestamp, root, properties, inputModifiers);
         }
 

src/Avalonia.ReactiveUI/Avalonia.ReactiveUI.csproj

@@ -2,6 +2,7 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <PackageId>Avalonia.ReactiveUI</PackageId>
+    <SignAssembly>True</SignAssembly>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\packages\Avalonia\Avalonia.csproj" />

src/Avalonia.Visuals/ApiCompatBaseline.txt

@@ -2,6 +2,8 @@ Compat issues with assembly Avalonia.Visuals:
 MembersMustExist : Member 'public void Avalonia.Media.DrawingContext.DrawGlyphRun(Avalonia.Media.IBrush, Avalonia.Media.GlyphRun, Avalonia.Point)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public Avalonia.Media.Typeface Avalonia.Media.FontManager.GetOrAddTypeface(Avalonia.Media.FontFamily, Avalonia.Media.FontStyle, Avalonia.Media.FontWeight)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public Avalonia.Media.Typeface Avalonia.Media.FontManager.MatchCharacter(System.Int32, Avalonia.Media.FontStyle, Avalonia.Media.FontWeight, Avalonia.Media.FontFamily, System.Globalization.CultureInfo)' does not exist in the implementation but it does exist in the contract.
+MembersMustExist : Member 'public Avalonia.Rect Avalonia.Media.Geometry.GetRenderBounds(Avalonia.Media.Pen)' does not exist in the implementation but it does exist in the contract.
+MembersMustExist : Member 'public System.Boolean Avalonia.Media.Geometry.StrokeContains(Avalonia.Media.Pen, Avalonia.Point)' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public Avalonia.Rect Avalonia.Media.GlyphRun.Bounds.get()' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public Avalonia.StyledProperty<Avalonia.Point> Avalonia.StyledProperty<Avalonia.Point> Avalonia.Media.GlyphRunDrawing.BaselineOriginProperty' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public Avalonia.Point Avalonia.Media.GlyphRunDrawing.BaselineOrigin.get()' does not exist in the implementation but it does exist in the contract.
@@ -34,4 +36,4 @@ InterfacesShouldHaveSameMembers : Interface member 'public System.Boolean Avalon
 MembersMustExist : Member 'public System.Boolean Avalonia.Platform.IFontManagerImpl.TryMatchCharacter(System.Int32, Avalonia.Media.FontStyle, Avalonia.Media.FontWeight, Avalonia.Media.FontFamily, System.Globalization.CultureInfo, Avalonia.Media.Fonts.FontKey)' does not exist in the implementation but it does exist in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public System.Boolean Avalonia.Platform.IFontManagerImpl.TryMatchCharacter(System.Int32, Avalonia.Media.FontStyle, Avalonia.Media.FontWeight, Avalonia.Media.FontFamily, System.Globalization.CultureInfo, Avalonia.Media.Typeface)' is present in the implementation but not in the contract.
 MembersMustExist : Member 'public Avalonia.Utilities.IRef<Avalonia.Platform.IRenderTargetBitmapImpl> Avalonia.Rendering.RenderLayer.Bitmap.get()' does not exist in the implementation but it does exist in the contract.
-Total Issues: 35
+Total Issues: 37

src/Avalonia.Visuals/Media/Drawing.cs

@@ -1,11 +1,19 @@
-using Avalonia.Platform;
+namespace Avalonia.Media
-
-namespace Avalonia.Media
 {
+    /// <summary>
+    /// Abstract class that describes a 2-D drawing.
+    /// </summary>
     public abstract class Drawing : AvaloniaObject
     {
+        /// <summary>
+        /// Draws this drawing to the given <see cref="DrawingContext"/>.
+        /// </summary>
+        /// <param name="context">The drawing context.</param>
         public abstract void Draw(DrawingContext context);
 
+        /// <summary>
+        /// Gets the drawing's bounding rectangle.
+        /// </summary>
         public abstract Rect GetBounds();
     }
 }

src/Avalonia.Visuals/Media/Geometry.cs

@@ -84,7 +84,7 @@ namespace Avalonia.Media
         /// </summary>
         /// <param name="pen">The stroke thickness.</param>
         /// <returns>The bounding rectangle.</returns>
-        public Rect GetRenderBounds(Pen pen) => PlatformImpl?.GetRenderBounds(pen) ?? Rect.Empty;
+        public Rect GetRenderBounds(IPen pen) => PlatformImpl?.GetRenderBounds(pen) ?? Rect.Empty;
 
         /// <summary>
         /// Indicates whether the geometry's fill contains the specified point.
@@ -102,7 +102,7 @@ namespace Avalonia.Media
         /// <param name="pen">The pen to use.</param>
         /// <param name="point">The point.</param>
         /// <returns><c>true</c> if the geometry contains the point; otherwise, <c>false</c>.</returns>
-        public bool StrokeContains(Pen pen, Point point)
+        public bool StrokeContains(IPen pen, Point point)
         {
             return PlatformImpl?.StrokeContains(pen, point) == true;
         }

src/Avalonia.Visuals/Media/GeometryDrawing.cs

@@ -1,12 +1,38 @@
-using Avalonia.Metadata;
+using Avalonia.Media.Immutable;
+using Avalonia.Metadata;
 
 namespace Avalonia.Media
 {
+    /// <summary>
+    /// Represents a drawing operation that combines 
+    /// a geometry with and brush and/or pen to produce rendered content.
+    /// </summary>
     public class GeometryDrawing : Drawing
     {
+        // Adding the Pen's stroke thickness here could yield wrong results due to transforms.
+        private static readonly IPen s_boundsPen = new ImmutablePen(Colors.Black.ToUint32(), 0);
+
+        /// <summary>
+        /// Defines the <see cref="Geometry"/> property.
+        /// </summary>
         public static readonly StyledProperty<Geometry> GeometryProperty =
             AvaloniaProperty.Register<GeometryDrawing, Geometry>(nameof(Geometry));
 
+        /// <summary>
+        /// Defines the <see cref="Brush"/> property.
+        /// </summary>
+        public static readonly StyledProperty<IBrush> BrushProperty =
+            AvaloniaProperty.Register<GeometryDrawing, IBrush>(nameof(Brush), Brushes.Transparent);
+
+        /// <summary>
+        /// Defines the <see cref="Pen"/> property.
+        /// </summary>
+        public static readonly StyledProperty<Pen> PenProperty =
+            AvaloniaProperty.Register<GeometryDrawing, Pen>(nameof(Pen));
+
+        /// <summary>
+        /// Gets or sets the <see cref="Avalonia.Media.Geometry"/> that describes the shape of this <see cref="GeometryDrawing"/>.
+        /// </summary>
         [Content]
         public Geometry Geometry
         {
@@ -14,18 +40,18 @@ namespace Avalonia.Media
             set => SetValue(GeometryProperty, value);
         }
 
-        public static readonly StyledProperty<IBrush> BrushProperty =
+        /// <summary>
-            AvaloniaProperty.Register<GeometryDrawing, IBrush>(nameof(Brush), Brushes.Transparent);
+        /// Gets or sets the <see cref="Avalonia.Media.IBrush"/> used to fill the interior of the shape described by this <see cref="GeometryDrawing"/>.
-
+        /// </summary>
         public IBrush Brush
         {
             get => GetValue(BrushProperty);
             set => SetValue(BrushProperty, value);
         }
 
-        public static readonly StyledProperty<Pen> PenProperty =
+        /// <summary>
-            AvaloniaProperty.Register<GeometryDrawing, Pen>(nameof(Pen));
+        /// Gets or sets the <see cref="Avalonia.Media.IPen"/> used to stroke this <see cref="GeometryDrawing"/>.
-
+        /// </summary>
         public IPen Pen
         {
             get => GetValue(PenProperty);
@@ -42,9 +68,7 @@ namespace Avalonia.Media
 
         public override Rect GetBounds()
         {
-            // adding the Pen's stroke thickness here could yield wrong results due to transforms
+            return Geometry?.GetRenderBounds(s_boundsPen) ?? Rect.Empty;
-            var pen = new Pen(Brushes.Black, 0);
-            return Geometry?.GetRenderBounds(pen) ?? new Rect();
         }
     }
 }

src/Avalonia.X11/XI2Manager.cs

@@ -13,7 +13,10 @@ namespace Avalonia.X11
         {
             XiEventType.XI_Motion,
             XiEventType.XI_ButtonPress,
-            XiEventType.XI_ButtonRelease
+            XiEventType.XI_ButtonRelease,
+            XiEventType.XI_Leave,
+            XiEventType.XI_Enter,
+            
         };
 
         private static readonly XiEventType[] MultiTouchEventTypes = new XiEventType[]
@@ -162,7 +165,9 @@ namespace Avalonia.X11
                    | XEventMask.Button4MotionMask
                    | XEventMask.Button5MotionMask
                    | XEventMask.ButtonPressMask
-                   | XEventMask.ButtonReleaseMask;
+                   | XEventMask.ButtonReleaseMask
+                   | XEventMask.LeaveWindowMask
+                   | XEventMask.EnterWindowMask;
         }
 
         public void OnWindowDestroyed(IntPtr xid) => _clients.Remove(xid);
@@ -175,14 +180,39 @@ namespace Avalonia.X11
                 _pointerDevice.Update(changed->Classes, changed->NumClasses);
             }
 
-            
+
             if ((xev->evtype >= XiEventType.XI_ButtonPress && xev->evtype <= XiEventType.XI_Motion)
-                || (xev->evtype>=XiEventType.XI_TouchBegin&&xev->evtype<=XiEventType.XI_TouchEnd))
+                || (xev->evtype >= XiEventType.XI_TouchBegin && xev->evtype <= XiEventType.XI_TouchEnd))
             {
                 var dev = (XIDeviceEvent*)xev;
                 if (_clients.TryGetValue(dev->EventWindow, out var client))
                     OnDeviceEvent(client, new ParsedDeviceEvent(dev));
             }
+
+            if (xev->evtype == XiEventType.XI_Leave || xev->evtype == XiEventType.XI_Enter)
+            {
+                var rev = (XIEnterLeaveEvent*)xev;
+                if (_clients.TryGetValue(rev->EventWindow, out var client))
+                    OnEnterLeaveEvent(client, ref *rev);
+            }
+        }
+
+        void OnEnterLeaveEvent(IXI2Client client, ref XIEnterLeaveEvent ev)
+        {
+            if (ev.evtype == XiEventType.XI_Leave)
+            {
+                var buttons = ParsedDeviceEvent.ParseButtonState(ev.buttons.MaskLen, ev.buttons.Mask);
+                var detail = ev.detail;
+                if ((detail == XiEnterLeaveDetail.XINotifyNonlinearVirtual ||
+                     detail == XiEnterLeaveDetail.XINotifyNonlinear ||
+                     detail == XiEnterLeaveDetail.XINotifyVirtual)
+                    && buttons == default)
+                {
+                    client.ScheduleXI2Input(new RawPointerEventArgs(client.MouseDevice, (ulong)ev.time.ToInt64(),
+                        client.InputRoot,
+                        RawPointerEventType.LeaveWindow, new Point(ev.event_x, ev.event_y), buttons));
+                }
+            }
         }
 
         void OnDeviceEvent(IXI2Client client, ParsedDeviceEvent ev)
@@ -284,6 +314,29 @@ namespace Avalonia.X11
         public int Detail { get; set; }
         public bool Emulated { get; set; }
         public Dictionary<int, double> Valuators { get; }
+
+        public static RawInputModifiers ParseButtonState(int len, byte* buttons)
+        {
+            RawInputModifiers rv = default;
+            if (len > 0)
+            {
+                if (XIMaskIsSet(buttons, 1))
+                    rv |= RawInputModifiers.LeftMouseButton;
+                if (XIMaskIsSet(buttons, 2))
+                    rv |= RawInputModifiers.MiddleMouseButton;
+                if (XIMaskIsSet(buttons, 3))
+                    rv |= RawInputModifiers.RightMouseButton;
+                if (len > 1)
+                {
+                    if (XIMaskIsSet(buttons, 8))
+                        rv |= RawInputModifiers.XButton1MouseButton;
+                    if (XIMaskIsSet(buttons, 9))
+                        rv |= RawInputModifiers.XButton2MouseButton;
+                }
+            }
+            return rv;
+        }
+        
         public ParsedDeviceEvent(XIDeviceEvent* ev)
         {
             Type = ev->evtype;
@@ -298,27 +351,16 @@ namespace Avalonia.X11
             if (state.HasFlag(XModifierMask.Mod4Mask))
                 Modifiers |= RawInputModifiers.Meta;
 
-            if (ev->buttons.MaskLen > 0)
+            Modifiers = ParseButtonState(ev->buttons.MaskLen, ev->buttons.Mask);
-            {
-                var buttons = ev->buttons.Mask;
-                if (XIMaskIsSet(buttons, 1))
-                    Modifiers |= RawInputModifiers.LeftMouseButton;
-                if (XIMaskIsSet(buttons, 2))
-                    Modifiers |= RawInputModifiers.MiddleMouseButton;
-                if (XIMaskIsSet(buttons, 3))
-                    Modifiers |= RawInputModifiers.RightMouseButton;
-                if (XIMaskIsSet(buttons, 8))
-                    Modifiers |= RawInputModifiers.XButton1MouseButton;
-                if (XIMaskIsSet(buttons, 9))
-                    Modifiers |= RawInputModifiers.XButton2MouseButton;
-            }
 
             Valuators = new Dictionary<int, double>();
             Position = new Point(ev->event_x, ev->event_y);
             var values = ev->valuators.Values;
-            for (var c = 0; c < ev->valuators.MaskLen * 8; c++)
+            if(ev->valuators.Mask != null)
-                if (XIMaskIsSet(ev->valuators.Mask, c))
+                for (var c = 0; c < ev->valuators.MaskLen * 8; c++)
-                    Valuators[c] = *values++;
+                    if (XIMaskIsSet(ev->valuators.Mask, c))
+                        Valuators[c] = *values++;
+            
             if (Type == XiEventType.XI_ButtonPress || Type == XiEventType.XI_ButtonRelease)
                 Button = ev->detail;
             Detail = ev->detail;

src/Avalonia.X11/XIStructs.cs

@@ -236,6 +236,34 @@ namespace Avalonia.X11
         public XIModifierState mods;
         public XIModifierState group;
     }
+    
+    [StructLayout(LayoutKind.Sequential)]
+    unsafe struct XIEnterLeaveEvent
+    {
+        public XEventName type; /* GenericEvent */
+        public UIntPtr serial; /* # of last request processed by server */
+        public Bool send_event; /* true if this came from a SendEvent request */
+        public IntPtr display; /* Display the event was read from */
+        public int extension; /* XI extension offset */
+        public XiEventType evtype;
+        public IntPtr time;
+        public int deviceid;
+        public int sourceid;
+        public XiEnterLeaveDetail detail;
+        public IntPtr RootWindow;
+        public IntPtr EventWindow;
+        public IntPtr ChildWindow;
+        public double root_x;
+        public double root_y;
+        public double event_x;
+        public double event_y;
+        public int mode;
+        public int focus;
+        public int same_screen;
+        public XIButtonState buttons;
+        public XIModifierState mods;
+        public XIModifierState group;
+    }
 
     [Flags]
     public enum XiDeviceEventFlags : int
@@ -286,5 +314,18 @@ namespace Avalonia.X11
         XI_BarrierLeave = 26,
         XI_LASTEVENT = XI_BarrierLeave,
     }
-    
+
+    enum XiEnterLeaveDetail
+    {
+        XINotifyAncestor = 0,
+        XINotifyVirtual = 1,
+        XINotifyInferior = 2,
+        XINotifyNonlinear = 3,
+        XINotifyNonlinearVirtual = 4,
+        XINotifyPointer = 5,
+        XINotifyPointerRoot = 6,
+        XINotifyDetailNone = 7
+
+    }
+
 }