Merge branch 'AvaloniaUI:master' into more-skia-caching

native/Avalonia.Native/src/OSX/Avalonia.Native.OSX.xcodeproj/project.pbxproj

@@ -43,6 +43,7 @@
 		523484CA26EA688F00EA0C2C /* trayicon.mm in Sources */ = {isa = PBXBuildFile; fileRef = 523484C926EA688F00EA0C2C /* trayicon.mm */; };
 		5B21A982216530F500CEE36E /* cursor.mm in Sources */ = {isa = PBXBuildFile; fileRef = 5B21A981216530F500CEE36E /* cursor.mm */; };
 		5B8BD94F215BFEA6005ED2A7 /* clipboard.mm in Sources */ = {isa = PBXBuildFile; fileRef = 5B8BD94E215BFEA6005ED2A7 /* clipboard.mm */; };
+		855EDC9F28C6546F00807998 /* PlatformBehaviorInhibition.mm in Sources */ = {isa = PBXBuildFile; fileRef = 855EDC9E28C6546F00807998 /* PlatformBehaviorInhibition.mm */; };
 		AB00E4F72147CA920032A60A /* main.mm in Sources */ = {isa = PBXBuildFile; fileRef = AB00E4F62147CA920032A60A /* main.mm */; };
 		AB1E522C217613570091CD71 /* OpenGL.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = AB1E522B217613570091CD71 /* OpenGL.framework */; };
 		AB661C1E2148230F00291242 /* AppKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = AB661C1D2148230F00291242 /* AppKit.framework */; };
@@ -95,6 +96,7 @@
 		5B21A981216530F500CEE36E /* cursor.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = cursor.mm; sourceTree = "<group>"; };
 		5B8BD94E215BFEA6005ED2A7 /* clipboard.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = clipboard.mm; sourceTree = "<group>"; };
 		5BF943652167AD1D009CAE35 /* cursor.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = cursor.h; sourceTree = "<group>"; };
+		855EDC9E28C6546F00807998 /* PlatformBehaviorInhibition.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = PlatformBehaviorInhibition.mm; sourceTree = "<group>"; };
 		AB00E4F62147CA920032A60A /* main.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = main.mm; sourceTree = "<group>"; };
 		AB1E522B217613570091CD71 /* OpenGL.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = OpenGL.framework; path = System/Library/Frameworks/OpenGL.framework; sourceTree = SDKROOT; };
 		AB661C1D2148230F00291242 /* AppKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = AppKit.framework; path = System/Library/Frameworks/AppKit.framework; sourceTree = SDKROOT; };
@@ -140,6 +142,7 @@
 		AB7A61E62147C814003C5833 = {
 			isa = PBXGroup;
 			children = (
+				855EDC9E28C6546F00807998 /* PlatformBehaviorInhibition.mm */,
 				BC11A5BC2608D58F0017BAD0 /* automation.h */,
 				BC11A5BD2608D58F0017BAD0 /* automation.mm */,
 				1A1852DB23E05814008F0DED /* deadlock.mm */,
@@ -288,6 +291,7 @@
 				1A3E5EAE23E9FB1300EDE661 /* cgl.mm in Sources */,
 				BC11A5BF2608D58F0017BAD0 /* automation.mm in Sources */,
 				37E2330F21583241000CB7E2 /* KeyTransform.mm in Sources */,
+				855EDC9F28C6546F00807998 /* PlatformBehaviorInhibition.mm in Sources */,
 				520624B322973F4100C4DCEF /* menu.mm in Sources */,
 				37A517B32159597E00FBA241 /* Screens.mm in Sources */,
 				1AFD334123E03C4F0042899B /* controlhost.mm in Sources */,

native/Avalonia.Native/src/OSX/PlatformBehaviorInhibition.mm

@@ -0,0 +1,39 @@
+#include "common.h"
+
+namespace
+{
+    id<NSObject> s_inhibitAppSleepHandle{};
+}
+
+class PlatformBehaviorInhibition : public ComSingleObject<IAvnPlatformBehaviorInhibition, &IID_IAvnCursorFactory>
+{
+public:
+    FORWARD_IUNKNOWN()
+    
+    virtual void SetInhibitAppSleep(bool inhibitAppSleep, char* reason) override
+    {
+        START_COM_CALL;
+        
+        @autoreleasepool
+        {
+            if (inhibitAppSleep && s_inhibitAppSleepHandle == nullptr)
+            {
+                NSActivityOptions options = NSActivityUserInitiatedAllowingIdleSystemSleep;
+                s_inhibitAppSleepHandle = [[NSProcessInfo processInfo] beginActivityWithOptions:options reason:[NSString stringWithUTF8String: reason]];
+            }
+            
+            if (!inhibitAppSleep)
+            {
+                s_inhibitAppSleepHandle = nullptr;
+            }
+        }
+    }
+};
+
+extern IAvnPlatformBehaviorInhibition* CreatePlatformBehaviorInhibition()
+{
+    @autoreleasepool
+    {
+        return new PlatformBehaviorInhibition();
+    }
+}

native/Avalonia.Native/src/OSX/common.h

@@ -26,6 +26,7 @@ extern IAvnTrayIcon* CreateTrayIcon();
 extern IAvnMenuItem* CreateAppMenuItem();
 extern IAvnMenuItem* CreateAppMenuItemSeparator();
 extern IAvnApplicationCommands* CreateApplicationCommands();
+extern IAvnPlatformBehaviorInhibition* CreatePlatformBehaviorInhibition();
 extern IAvnNativeControlHost* CreateNativeControlHost(NSView* parent);
 extern IAvnPlatformSettings* CreatePlatformSettings();
 extern void SetAppMenu(IAvnMenu *menu);

native/Avalonia.Native/src/OSX/main.mm

@@ -408,6 +408,17 @@ public:
             return S_OK;
         }
     }
+
+    virtual HRESULT CreatePlatformBehaviorInhibition(IAvnPlatformBehaviorInhibition** ppv) override
+    {
+        START_COM_CALL;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreatePlatformBehaviorInhibition();
+            return S_OK;
+        }
+    }
 };
 
 extern "C" IAvaloniaNativeFactory* CreateAvaloniaNative()

readme.md

@@ -1,3 +1,5 @@
+[![GH_Banner](https://user-images.githubusercontent.com/552074/218457976-92e76834-9e22-4e35-acfa-aa50281bc0f9.png)](https://avaloniaui.net/xpf)
+
 [![Telegram](https://raw.githubusercontent.com/Patrolavia/telegram-badge/master/chat.svg)](https://t.me/Avalonia)
 [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/AvaloniaUI/Avalonia?utm_campaign=pr-badge&utm_content=badge&utm_medium=badge&utm_source=badge) [![Discord](https://img.shields.io/badge/discord-join%20chat-46BC99)]( https://aka.ms/dotnet-discord) [![Build Status](https://dev.azure.com/AvaloniaUI/AvaloniaUI/_apis/build/status/AvaloniaUI.Avalonia)](https://dev.azure.com/AvaloniaUI/AvaloniaUI/_build/latest?definitionId=4) [![Backers on Open Collective](https://opencollective.com/Avalonia/backers/badge.svg)](#backers) [![Sponsors on Open Collective](https://opencollective.com/Avalonia/sponsors/badge.svg)](#sponsors) ![License](https://img.shields.io/github/license/avaloniaui/avalonia.svg)
 <br />

src/Avalonia.Base/AvaloniaObject.cs

@@ -277,8 +277,8 @@ namespace Avalonia
         /// <param name="property">The property.</param>
         /// <returns>True if the property is set, otherwise false.</returns>
         /// <remarks>
-        /// Checks whether a value is assigned to the property, or that there is a binding to the
-        /// property that is producing a value other than <see cref="AvaloniaProperty.UnsetValue"/>.
+        /// Returns true if <paramref name="property"/> is a styled property which has a value
+        /// assigned to it or a binding targeting it; otherwise false.
         /// </remarks>
         public bool IsSet(AvaloniaProperty property)
         {

src/Avalonia.Base/Platform/IPlatformBehaviorInhibition.cs

@@ -0,0 +1,12 @@
+using System.Threading.Tasks;
+
+namespace Avalonia.Platform
+{
+    /// <summary>
+    /// Allows to inhibit platform specific behavior.
+    /// </summary>
+    public interface IPlatformBehaviorInhibition
+    {
+        Task SetInhibitAppSleep(bool inhibitAppSleep, string reason);
+    }
+}

src/Avalonia.Base/PropertyStore/BindingEntryBase.cs

@@ -16,6 +16,8 @@ namespace Avalonia.PropertyStore
         private IDisposable? _subscription;
         private bool _hasValue;
         private TValue? _value;
+        private TValue? _defaultValue;
+        private bool _isDefaultValueInitialized;
 
         protected BindingEntryBase(
             ValueFrame frame,
@@ -89,6 +91,7 @@ namespace Avalonia.PropertyStore
 
         protected abstract BindingValue<TValue> ConvertAndValidate(TSource value);
         protected abstract BindingValue<TValue> ConvertAndValidate(BindingValue<TSource> value);
+        protected abstract TValue GetDefaultValue(Type ownerType);
 
         protected virtual void Start(bool produceValue)
         {
@@ -104,17 +107,6 @@ namespace Avalonia.PropertyStore
             };
         }
 
-        private void ClearValue()
-        {
-            if (_hasValue)
-            {
-                _hasValue = false;
-                _value = default;
-                if (_subscription is not null)
-                    Frame.Owner?.OnBindingValueCleared(Property, Frame.Priority);
-            }
-        }
-
         private void SetValue(BindingValue<TValue> value)
         {
             static void Execute(BindingEntryBase<TValue, TSource> instance, BindingValue<TValue> value)
@@ -124,24 +116,20 @@ namespace Avalonia.PropertyStore
 
                 LoggingUtils.LogIfNecessary(instance.Frame.Owner.Owner, instance.Property, value);
 
-                if (value.HasValue)
-                {
-                    if (!instance._hasValue || !EqualityComparer<TValue>.Default.Equals(instance._value, value.Value))
-                    {
-                        instance._value = value.Value;
-                        instance._hasValue = true;
-                        if (instance._subscription is not null && instance._subscription != s_creatingQuiet)
-                            instance.Frame.Owner?.OnBindingValueChanged(instance, instance.Frame.Priority);
-                    }
-                }
-                else if (value.Type != BindingValueType.DoNothing)
+                var effectiveValue = value.HasValue ? value.Value : instance.GetCachedDefaultValue();
+
+                if (!instance._hasValue || !EqualityComparer<TValue>.Default.Equals(instance._value, effectiveValue))
                 {
-                    instance.ClearValue();
+                    instance._value = effectiveValue;
+                    instance._hasValue = true;
                     if (instance._subscription is not null && instance._subscription != s_creatingQuiet)
-                        instance.Frame.Owner?.OnBindingValueCleared(instance.Property, instance.Frame.Priority);
+                        instance.Frame.Owner?.OnBindingValueChanged(instance, instance.Frame.Priority);
                 }
             }
 
+            if (value.Type == BindingValueType.DoNothing)
+                return;
+
             if (Dispatcher.UIThread.CheckAccess())
             {
                 Execute(this, value);
@@ -161,5 +149,16 @@ namespace Avalonia.PropertyStore
             _subscription = null;
             Frame.OnBindingCompleted(this);
         }
+
+        private TValue GetCachedDefaultValue()
+        {
+            if (!_isDefaultValueInitialized)
+            {
+                _defaultValue = GetDefaultValue(Frame.Owner!.Owner.GetType());
+                _isDefaultValueInitialized = true;
+            }
+
+            return _defaultValue!;
+        }
     }
 }

src/Avalonia.Base/PropertyStore/LocalValueBindingObserver.cs

@@ -10,6 +10,8 @@ namespace Avalonia.PropertyStore
     {
         private readonly ValueStore _owner;
         private IDisposable? _subscription;
+        private T? _defaultValue;
+        private bool _isDefaultValueInitialized;
 
         public LocalValueBindingObserver(ValueStore owner, StyledProperty<T> property)
         {
@@ -41,26 +43,28 @@ namespace Avalonia.PropertyStore
 
         public void OnNext(T value)
         {
-            static void Execute(ValueStore owner, StyledProperty<T> property, T value)
+            static void Execute(LocalValueBindingObserver<T> instance, T value)
             {
-                if (property.ValidateValue?.Invoke(value) != false)
-                    owner.SetValue(property, value, BindingPriority.LocalValue);
-                else
-                    owner.ClearLocalValue(property);
+                var owner = instance._owner;
+                var property = instance.Property;
+
+                if (property.ValidateValue?.Invoke(value) == false)
+                    value = instance.GetCachedDefaultValue();
+
+                owner.SetValue(property, value, BindingPriority.LocalValue);
             }
 
             if (Dispatcher.UIThread.CheckAccess())
             {
-                Execute(_owner, Property, value);
+                Execute(this, value);
             }
             else
             {
                 // To avoid allocating closure in the outer scope we need to capture variables
                 // locally. This allows us to skip most of the allocations when on UI thread.
-                var instance = _owner;
-                var property = Property;
+                var instance = this;
                 var newValue = value;
-                Dispatcher.UIThread.Post(() => Execute(instance, property, newValue));
+                Dispatcher.UIThread.Post(() => Execute(instance, newValue));
             }
         }
 
@@ -74,11 +78,21 @@ namespace Avalonia.PropertyStore
                 LoggingUtils.LogIfNecessary(owner.Owner, property, value);
 
                 if (value.HasValue)
-                    owner.SetValue(property, value.Value, BindingPriority.LocalValue);
-                else if (value.Type != BindingValueType.DataValidationError)
-                    owner.ClearLocalValue(property);
+                {
+                    var effectiveValue = value.Value;
+                    if (property.ValidateValue?.Invoke(effectiveValue) == false)
+                        effectiveValue = instance.GetCachedDefaultValue();
+                    owner.SetValue(property, effectiveValue, BindingPriority.LocalValue);
+                }
+                else
+                {
+                    owner.SetValue(property, instance.GetCachedDefaultValue(), BindingPriority.LocalValue);
+                }
             }
 
+            if (value.Type is BindingValueType.DoNothing or BindingValueType.DataValidationError)
+                return;
+
             if (Dispatcher.UIThread.CheckAccess())
             {
                 Execute(this, value);
@@ -92,5 +106,16 @@ namespace Avalonia.PropertyStore
                 Dispatcher.UIThread.Post(() => Execute(instance, newValue));
             }
         }
+
+        private T GetCachedDefaultValue()
+        {
+            if (!_isDefaultValueInitialized)
+            {
+                _defaultValue = Property.GetDefaultValue(_owner.Owner.GetType());
+                _isDefaultValueInitialized = true;
+            }
+
+            return _defaultValue!;
+        }
     }
 }

src/Avalonia.Base/PropertyStore/LocalValueUntypedBindingObserver.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Security.Cryptography;
 using Avalonia.Data;
 using Avalonia.Threading;
 
@@ -10,6 +9,8 @@ namespace Avalonia.PropertyStore
     {
         private readonly ValueStore _owner;
         private IDisposable? _subscription;
+        private T? _defaultValue;
+        private bool _isDefaultValueInitialized;
 
         public LocalValueUntypedBindingObserver(ValueStore owner, StyledProperty<T> property)
         {
@@ -49,11 +50,7 @@ namespace Avalonia.PropertyStore
 
                 if (value == AvaloniaProperty.UnsetValue)
                 {
-                    owner.ClearLocalValue(property);
-                }
-                else if (value == BindingOperations.DoNothing)
-                {
-                    // Do nothing!
+                    owner.SetValue(property, instance.GetCachedDefaultValue(), BindingPriority.LocalValue);
                 }
                 else if (UntypedValueUtils.TryConvertAndValidate(property, value, out var typedValue))
                 {
@@ -61,11 +58,14 @@ namespace Avalonia.PropertyStore
                 }
                 else
                 {
-                    owner.ClearLocalValue(property);
+                    owner.SetValue(property, instance.GetCachedDefaultValue(), BindingPriority.LocalValue);
                     LoggingUtils.LogInvalidValue(owner.Owner, property, typeof(T), value);
                 }
             }
 
+            if (value == BindingOperations.DoNothing)
+                return;
+
             if (Dispatcher.UIThread.CheckAccess())
             {
                 Execute(this, value);
@@ -79,5 +79,16 @@ namespace Avalonia.PropertyStore
                 Dispatcher.UIThread.Post(() => Execute(instance, newValue));
             }
         }
+
+        private T GetCachedDefaultValue()
+        {
+            if (!_isDefaultValueInitialized)
+            {
+                _defaultValue = Property.GetDefaultValue(_owner.Owner.GetType());
+                _isDefaultValueInitialized = true;
+            }
+
+            return _defaultValue!;
+        }
     }
 }

src/Avalonia.Base/PropertyStore/SourceUntypedBindingEntry.cs

@@ -31,5 +31,7 @@ namespace Avalonia.PropertyStore
         {
             throw new NotSupportedException();
         }
+
+        protected override TTarget GetDefaultValue(Type ownerType) => Property.GetDefaultValue(ownerType);
     }
 }

src/Avalonia.Base/PropertyStore/TypedBindingEntry.cs

@@ -48,5 +48,7 @@ namespace Avalonia.PropertyStore
             
             return value;
         }
+
+        protected override T GetDefaultValue(Type ownerType) => Property.GetDefaultValue(ownerType);
     }
 }

src/Avalonia.Base/PropertyStore/UntypedBindingEntry.cs

@@ -29,5 +29,10 @@ namespace Avalonia.PropertyStore
         {
             throw new NotSupportedException();
         }
+
+        protected override object? GetDefaultValue(Type ownerType)
+        {
+            return ((IStyledPropertyMetadata)Property.GetMetadata(ownerType)).DefaultValue;
+        }
     }
 }

src/Avalonia.Base/PropertyStore/ValueStore.cs

@@ -380,23 +380,6 @@ namespace Avalonia.PropertyStore
             }
         }
 
-        /// <summary>
-        /// Called by non-LocalValue binding entries to re-evaluate the effective value when the
-        /// binding produces an unset value.
-        /// </summary>
-        /// <param name="property">The bound property.</param>
-        /// <param name="priority">The priority of binding which produced a new value.</param>
-        public void OnBindingValueCleared(AvaloniaProperty property, BindingPriority priority)
-        {
-            Debug.Assert(priority != BindingPriority.LocalValue);
-
-            if (TryGetEffectiveValue(property, out var existing))
-            {
-                if (priority <= existing.Priority)
-                    ReevaluateEffectiveValue(property, existing);
-            }
-        }
-
         /// <summary>
         /// Called by a <see cref="ValueFrame"/> when its <see cref="ValueFrame.IsActive"/>
         /// state changes.

src/Avalonia.Controls/PlatformInhibitionType.cs

@@ -0,0 +1,13 @@
+namespace Avalonia.Controls
+{
+    /// <summary>
+    /// A platform specific behavior that can be inhibited.
+    /// </summary>
+    public enum PlatformInhibitionType
+    {
+        /// <summary>
+        /// When inhibited, prevents the app from being put to sleep or being given a lower priority when not in focus.
+        /// </summary>
+        AppSleep
+    }
+}

src/Avalonia.Controls/TopLevel.cs

@@ -20,6 +20,7 @@ using Avalonia.Styling;
 using Avalonia.Utilities;
 using Avalonia.Input.Platform;
 using System.Linq;
+using System.Threading.Tasks;
 
 namespace Avalonia.Controls
 {
@@ -570,6 +571,30 @@ namespace Avalonia.Controls
         /// <param name="e">The event args.</param>
         protected virtual void OnClosed(EventArgs e) => Closed?.Invoke(this, e);
 
+        /// <summary>
+        /// Requests a <see cref="PlatformInhibitionType"/> to be inhibited.
+        /// The behavior remains inhibited until the return value is disposed.
+        /// The available set of <see cref="PlatformInhibitionType"/>s depends on the platform.
+        /// If a behavior is inhibited on a platform where this type is not supported the request will have no effect.
+        /// </summary>
+        protected async Task<IDisposable> RequestPlatformInhibition(PlatformInhibitionType type, string reason)
+        {
+            var platformBehaviorInhibition = PlatformImpl?.TryGetFeature<IPlatformBehaviorInhibition>();
+            if (platformBehaviorInhibition == null)
+            {
+                return Disposable.Create(() => { });
+            }
+
+            switch (type)
+            {
+                case PlatformInhibitionType.AppSleep:
+                    await platformBehaviorInhibition.SetInhibitAppSleep(true, reason);
+                    return Disposable.Create(() => platformBehaviorInhibition.SetInhibitAppSleep(false, reason).Wait());
+                default:
+                    return Disposable.Create(() => { });
+            }
+        }
+
         /// <summary>
         /// Tries to get a service from an <see cref="IAvaloniaDependencyResolver"/>, logging a
         /// warning if not found.

src/Avalonia.Native/AvaloniaNativePlatform.cs

@@ -158,25 +158,4 @@ namespace Avalonia.Native
             throw new NotImplementedException();
         }
     }
-
-    public class AvaloniaNativeMacOptions
-    {
-        private readonly IAvnMacOptions _opts;
-        private bool _showInDock;
-        internal AvaloniaNativeMacOptions(IAvnMacOptions opts)
-        {
-            _opts = opts;
-            ShowInDock = true;
-        }
-
-        public bool ShowInDock
-        {
-            get => _showInDock;
-            set
-            {
-                _showInDock = value;
-                _opts.SetShowInDock(value ? 1 : 0);
-            }
-        }
-    }
 }

src/Avalonia.Native/PlatformBehaviorInhibition.cs

@@ -0,0 +1,20 @@
+using System.Threading.Tasks;
+using Avalonia.Native.Interop;
+using Avalonia.Platform;
+
+namespace Avalonia.Native
+{
+    internal class PlatformBehaviorInhibition : IPlatformBehaviorInhibition
+    {
+        readonly IAvnPlatformBehaviorInhibition _native;
+
+        internal PlatformBehaviorInhibition(IAvnPlatformBehaviorInhibition native)
+            => _native = native;
+
+        public Task SetInhibitAppSleep(bool inhibitAppSleep, string reason)
+        {
+            _native.SetInhibitAppSleep(inhibitAppSleep ? 1 : 0, reason);
+            return Task.CompletedTask;
+        }
+    }
+}

src/Avalonia.Native/WindowImplBase.cs

@@ -63,6 +63,7 @@ namespace Avalonia.Native
         private GlPlatformSurface _glSurface;
         private NativeControlHostImpl _nativeControlHost;
         private IStorageProvider _storageProvider;
+        private PlatformBehaviorInhibition _platformBehaviorInhibition;
 
         internal WindowBaseImpl(IAvaloniaNativeFactory factory, AvaloniaNativePlatformOptions opts,
             AvaloniaNativeGlPlatformGraphics glFeature)
@@ -88,6 +89,7 @@ namespace Avalonia.Native
             _savedScaling = RenderScaling;
             _nativeControlHost = new NativeControlHostImpl(_native.CreateNativeControlHost());
             _storageProvider = new SystemDialogs(this, _factory.CreateSystemDialogs());
+            _platformBehaviorInhibition = new PlatformBehaviorInhibition(_factory.CreatePlatformBehaviorInhibition());
 
             var monitor = Screen.AllScreens.OrderBy(x => x.Scaling)
                     .FirstOrDefault(m => m.Bounds.Contains(Position));
@@ -521,6 +523,11 @@ namespace Avalonia.Native
                 return _storageProvider;
             }
 
+            if (featureType == typeof(IPlatformBehaviorInhibition))
+            {
+                return _platformBehaviorInhibition;
+            }
+
             return null;
         }
 

src/Avalonia.Native/avn.idl

@@ -503,6 +503,7 @@ interface IAvaloniaNativeFactory : IUnknown
      HRESULT CreateTrayIcon(IAvnTrayIcon** ppv);
      HRESULT CreateApplicationCommands(IAvnApplicationCommands** ppv);
      HRESULT CreatePlatformSettings(IAvnPlatformSettings** ppv);
+     HRESULT CreatePlatformBehaviorInhibition(IAvnPlatformBehaviorInhibition** ppv);
 }
 
 [uuid(233e094f-9b9f-44a3-9a6e-6948bbdd9fb1)]
@@ -924,3 +925,9 @@ interface IAvnPlatformSettings : IUnknown
     uint GetAccentColor();
     void RegisterColorsChange(IAvnActionCallback* callback);
 }
+
+[uuid(12edf00d-5803-4d3f-9947-b4840e5e9372)]
+interface IAvnPlatformBehaviorInhibition : IUnknown
+{
+    void SetInhibitAppSleep(bool inhibitAppSleep, char* reason);
+}

tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Binding.cs

@@ -372,6 +372,20 @@ namespace Avalonia.Base.UnitTests
             Assert.Null(target.GetValue(property));
         }
 
+        [Fact]
+        public void LocalValue_Bind_Generic_To_ValueType_Accepts_UnsetValue()
+        {
+            var target = new Class1();
+            var source = new Subject<BindingValue<double>>();
+
+            target.Bind(Class1.QuxProperty, source);
+            source.OnNext(6.7);
+            source.OnNext(BindingValue<double>.Unset);
+
+            Assert.Equal(5.6, target.GetValue(Class1.QuxProperty));
+            Assert.True(target.IsSet(Class1.QuxProperty));
+        }
+
         [Fact]
         public void LocalValue_Bind_NonGeneric_To_ValueType_Accepts_UnsetValue()
         {
@@ -383,7 +397,7 @@ namespace Avalonia.Base.UnitTests
             source.OnNext(AvaloniaProperty.UnsetValue);
 
             Assert.Equal(5.6, target.GetValue(Class1.QuxProperty));
-            Assert.False(target.IsSet(Class1.QuxProperty));
+            Assert.True(target.IsSet(Class1.QuxProperty));
         }
 
         [Fact]
@@ -397,7 +411,7 @@ namespace Avalonia.Base.UnitTests
             source.OnNext(AvaloniaProperty.UnsetValue);
 
             Assert.Equal(5.6, target.GetValue(Class1.QuxProperty));
-            Assert.False(target.IsSet(Class1.QuxProperty));
+            Assert.True(target.IsSet(Class1.QuxProperty));
         }
 
         [Fact]
@@ -1285,6 +1299,24 @@ namespace Avalonia.Base.UnitTests
             subscription.Dispose();
         }
 
+        [Theory]
+        [InlineData(BindingPriority.LocalValue)]
+        [InlineData(BindingPriority.Style)]
+        public void Binding_Producing_UnsetValue_Does_Not_Cause_Unsubscribe(BindingPriority priority)
+        {
+            var target = new Class1();
+            var source = new Subject<BindingValue<string>>();
+            
+            target.Bind(Class1.FooProperty, source, priority);
+
+            source.OnNext("foo");
+            Assert.Equal("foo", target.GetValue(Class1.FooProperty));
+            source.OnNext(BindingValue<string>.Unset);
+            Assert.Equal("foodefault", target.GetValue(Class1.FooProperty));
+            source.OnNext("bar");
+            Assert.Equal("bar", target.GetValue(Class1.FooProperty));
+        }
+
         [Fact]
         public void Produces_Correct_Values_And_Base_Values_With_Multiple_Animation_Bindings()
         {

tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Validation.cs

@@ -66,7 +66,7 @@ namespace Avalonia.Base.UnitTests
         }
 
         [Fact]
-        public void Reverts_To_Lower_Priority_If_Style_Binding_Fails_Validation()
+        public void Reverts_To_DefaultValue_If_Style_Binding_Fails_Validation_2()
         {
             var target = new Class1();
             var source = new Subject<int>();
@@ -75,7 +75,21 @@ namespace Avalonia.Base.UnitTests
             target.Bind(Class1.FooProperty, source, BindingPriority.StyleTrigger);
             source.OnNext(150);
 
-            Assert.Equal(10, target.GetValue(Class1.FooProperty));
+            Assert.Equal(11, target.GetValue(Class1.FooProperty));
+        }
+
+        [Theory]
+        [InlineData(BindingPriority.LocalValue)]
+        [InlineData(BindingPriority.Style)]
+        public void Reverts_To_DefaultValue_If_Style_Binding_Fails_Validation_3(BindingPriority priority)
+        {
+            var target = new Class1();
+            var source = new Subject<BindingValue<int>>();
+
+            target.Bind(Class1.FooProperty, source, priority);
+            source.OnNext(150);
+
+            Assert.Equal(11, target.GetValue(Class1.FooProperty));
         }
 
         [Fact]

tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ResourceDictionaryTests.cs

@@ -307,7 +307,30 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 Assert.True(buttonResources.ContainsDeferredKey("Red"));
             }
         }
-        
+
+        [Fact]
+        public void Dynamically_Changing_Referenced_Resources_Works_With_DynamicResource()
+        {
+            var xaml = @"
+<UserControl xmlns='https://github.com/avaloniaui'
+     xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+  <UserControl.Resources>
+    <Color x:Key='color'>Red</Color>
+    <SolidColorBrush x:Key='brush' Color='{DynamicResource color}' />
+  </UserControl.Resources>
+</UserControl>";
+
+            var userControl = (UserControl)AvaloniaRuntimeXamlLoader.Load(xaml);
+
+            Assert.Equal(Colors.Red, ((ISolidColorBrush)userControl.FindResource("brush")!).Color);
+
+            userControl.Resources.Remove("color");
+            Assert.Equal(default, ((ISolidColorBrush)userControl.FindResource("brush")!).Color);
+
+            userControl.Resources.Add("color", Colors.Blue);
+            Assert.Equal(Colors.Blue, ((ISolidColorBrush)userControl.FindResource("brush")!).Color);
+        }
+
         private IDisposable StyledWindow(params (string, string)[] assets)
         {
             var services = TestServices.StyledWindow.With(