Merge branch 'master' into fixes/resizing-wasm

src/Avalonia.Controls/ApiCompatBaseline.txt

@@ -36,6 +36,7 @@ CannotRemoveBaseTypeOrInterface : Type 'Avalonia.Controls.WindowBase' does not i
 InterfacesShouldHaveSameMembers : Interface member 'public System.EventHandler<Avalonia.Controls.ApplicationLifetimes.ShutdownRequestedEventArgs> Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime.ShutdownRequested' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime.add_ShutdownRequested(System.EventHandler<Avalonia.Controls.ApplicationLifetimes.ShutdownRequestedEventArgs>)' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime.remove_ShutdownRequested(System.EventHandler<Avalonia.Controls.ApplicationLifetimes.ShutdownRequestedEventArgs>)' is present in the implementation but not in the contract.
+InterfacesShouldHaveSameMembers : Interface member 'public System.Boolean Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime.TryShutdown(System.Int32)' is present in the implementation but not in the contract.
 CannotRemoveBaseTypeOrInterface : Type 'Avalonia.Controls.Embedding.EmbeddableControlRoot' does not implement interface 'Avalonia.Utilities.IWeakSubscriber<Avalonia.Controls.ResourcesChangedEventArgs>' in the implementation but it does in the contract.
 MembersMustExist : Member 'public System.Action<Avalonia.Size> Avalonia.Controls.Embedding.Offscreen.OffscreenTopLevelImplBase.Resized.get()' does not exist in the implementation but it does exist in the contract.
 MembersMustExist : Member 'public void Avalonia.Controls.Embedding.Offscreen.OffscreenTopLevelImplBase.Resized.set(System.Action<Avalonia.Size>)' does not exist in the implementation but it does exist in the contract.
@@ -62,4 +63,4 @@ InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Platfor
 MembersMustExist : Member 'public void Avalonia.Platform.IWindowImpl.Resize(Avalonia.Size)' does not exist in the implementation but it does exist in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Platform.IWindowImpl.Resize(Avalonia.Size, Avalonia.Platform.PlatformResizeReason)' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public Avalonia.Platform.ITrayIconImpl Avalonia.Platform.IWindowingPlatform.CreateTrayIcon()' is present in the implementation but not in the contract.
-Total Issues: 63
+Total Issues: 64

src/Avalonia.Controls/ApplicationLifetimes/ClassicDesktopStyleApplicationLifetime.cs

@@ -76,36 +76,21 @@ namespace Avalonia.Controls.ApplicationLifetimes
                 return;
 
             if (ShutdownMode == ShutdownMode.OnLastWindowClose && _windows.Count == 0)
-                Shutdown();
-            else if (ShutdownMode == ShutdownMode.OnMainWindowClose && window == MainWindow)
-                Shutdown();
+                TryShutdown();
+            else if (ShutdownMode == ShutdownMode.OnMainWindowClose && ReferenceEquals(window, MainWindow))
+                TryShutdown();
         }
 
         public void Shutdown(int exitCode = 0)
         {
-            if (_isShuttingDown)
-                throw new InvalidOperationException("Application is already shutting down.");
-            
-            _exitCode = exitCode;
-            _isShuttingDown = true;
+            DoShutdown(new ShutdownRequestedEventArgs(), true, exitCode);
+        }
 
-            try
-            {
-                foreach (var w in Windows)
-                    w.Close();
-                var e = new ControlledApplicationLifetimeExitEventArgs(exitCode);
-                Exit?.Invoke(this, e);
-                _exitCode = e.ApplicationExitCode;                
-            }
-            finally
-            {
-                _cts?.Cancel();
-                _cts = null;
-                _isShuttingDown = false;
-            }
+        public bool TryShutdown(int exitCode = 0)
+        {
+            return DoShutdown(new ShutdownRequestedEventArgs(), false, exitCode);
         }
         
-        
         public int Start(string[] args)
         {
             Startup?.Invoke(this, new ControlledApplicationLifetimeStartupEventArgs(args));
@@ -114,7 +99,10 @@ namespace Avalonia.Controls.ApplicationLifetimes
             
             if(options != null && options.ProcessUrlActivationCommandLine && args.Length > 0)
             {
-                ((IApplicationPlatformEvents)Application.Current).RaiseUrlsOpened(args);
+                if (Application.Current is IApplicationPlatformEvents events)
+                {
+                    events.RaiseUrlsOpened(args);
+                }
             }
 
             var lifetimeEvents = AvaloniaLocator.Current.GetService<IPlatformLifetimeEventsImpl>(); 
@@ -145,23 +133,57 @@ namespace Avalonia.Controls.ApplicationLifetimes
             if (_activeLifetime == this)
                 _activeLifetime = null;
         }
-        
-        private void OnShutdownRequested(object sender, ShutdownRequestedEventArgs e)
+
+        private bool DoShutdown(ShutdownRequestedEventArgs e, bool force = false, int exitCode = 0)
         {
-            ShutdownRequested?.Invoke(this, e);
+            if (!force)
+            {
+                ShutdownRequested?.Invoke(this, e);
 
-            if (e.Cancel)
-                return;
+                if (e.Cancel)
+                    return false;
+
+                if (_isShuttingDown)
+                    throw new InvalidOperationException("Application is already shutting down.");
+            }
+
+            _exitCode = exitCode;
+            _isShuttingDown = true;
 
-            // When an OS shutdown request is received, try to close all non-owned windows. Windows can cancel
-            // shutdown by setting e.Cancel = true in the Closing event. Owned windows will be shutdown by their
-            // owners.
-            foreach (var w in Windows)
-                if (w.Owner is null)
-                    w.Close();
-            if (Windows.Count > 0)
-                e.Cancel = true;
+            try
+            {
+                // When an OS shutdown request is received, try to close all non-owned windows. Windows can cancel
+                // shutdown by setting e.Cancel = true in the Closing event. Owned windows will be shutdown by their
+                // owners.
+                foreach (var w in Windows)
+                {
+                    if (w.Owner is null)
+                    {
+                        w.Close();
+                    }
+                }
+
+                if (!force && Windows.Count > 0)
+                {
+                    e.Cancel = true;
+                    return false;
+                }
+
+                var args = new ControlledApplicationLifetimeExitEventArgs(exitCode);
+                Exit?.Invoke(this, args);
+                _exitCode = args.ApplicationExitCode;                
+            }
+            finally
+            {
+                _cts?.Cancel();
+                _cts = null;
+                _isShuttingDown = false;
+            }
+
+            return true;
         }
+        
+        private void OnShutdownRequested(object sender, ShutdownRequestedEventArgs e) => DoShutdown(e);
     }
     
     public class ClassicDesktopStyleApplicationLifetimeOptions

src/Avalonia.Controls/ApplicationLifetimes/IClassicDesktopStyleApplicationLifetime.cs

@@ -9,6 +9,12 @@ namespace Avalonia.Controls.ApplicationLifetimes
     /// </summary>
     public interface IClassicDesktopStyleApplicationLifetime : IControlledApplicationLifetime
     {
+        /// <summary>
+        /// Tries to Shutdown the application. <see cref="ShutdownRequested" /> event can be used to cancel the shutdown.
+        /// </summary>
+        /// <param name="exitCode">An integer exit code for an application. The default exit code is 0.</param>
+        bool TryShutdown(int exitCode = 0);
+
         /// <summary>
         /// Gets the arguments passed to the
         /// <see cref="ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime{T}(T, string[], ShutdownMode)"/>

src/Avalonia.Native/AvaloniaNativeMenuExporter.cs

@@ -133,9 +133,13 @@ namespace Avalonia.Native
             var quitItem = new NativeMenuItem("Quit") { Gesture = new KeyGesture(Key.Q, KeyModifiers.Meta) };
             quitItem.Click += (_, _) =>
             {
-                if (Application.Current is { ApplicationLifetime: IControlledApplicationLifetime lifetime })
+                if (Application.Current is { ApplicationLifetime: IClassicDesktopStyleApplicationLifetime lifetime })
                 {
-                    lifetime.Shutdown();
+                    lifetime.TryShutdown();
+                }
+                else if(Application.Current is {ApplicationLifetime: IControlledApplicationLifetime controlledLifetime})
+                {
+                    controlledLifetime.Shutdown();
                 }
             };
 

src/Avalonia.Themes.Fluent/Controls/ButtonSpinner.xaml

@@ -1,7 +1,8 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:sys="clr-namespace:System;assembly=netstandard"
-        xmlns:converters="clr-namespace:Avalonia.Controls.Converters;assembly=Avalonia.Controls">
+        xmlns:converters="clr-namespace:Avalonia.Controls.Converters;assembly=Avalonia.Controls"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20"
             Background="Black">

src/Avalonia.Themes.Fluent/Controls/CalendarDatePicker.xaml

@@ -7,7 +7,8 @@
 
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="clr-namespace:System;assembly=netstandard">
+        xmlns:sys="clr-namespace:System;assembly=netstandard"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Margin="20, 20, 20, 200">
       <CalendarDatePicker Width="200"

src/Avalonia.Themes.Fluent/Controls/CalendarItem.xaml

@@ -6,7 +6,9 @@
 -->
 
 <Styles xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True"
+        x:DataType="CalendarItem">
   <Design.PreviewWith>
     <Border Padding="20">
       <Calendar />

src/Avalonia.Themes.Fluent/Controls/DataValidationErrors.xaml

@@ -1,6 +1,8 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="using:System">
+        xmlns:sys="using:System"
+        x:CompileBindings="True"
+        x:DataType="DataValidationErrors">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">
@@ -27,7 +29,7 @@
   <Style Selector="DataValidationErrors">
     <Style.Resources>
       <DataTemplate x:Key="InlineDataValidationErrorTemplate">
-        <ItemsControl Items="{Binding}" TextBlock.Foreground="{DynamicResource SystemControlErrorTextForegroundBrush}">
+        <ItemsControl Items="{Binding}" x:DataType="DataValidationErrors" TextBlock.Foreground="{DynamicResource SystemControlErrorTextForegroundBrush}">
           <ItemsControl.Styles>
             <Style Selector="TextBlock">
               <Setter Property="TextWrapping" Value="Wrap" />
@@ -54,7 +56,7 @@
         </DockPanel>
       </ControlTemplate>
 
-      <DataTemplate x:Key="TooltipDataValidationErrorTemplate">
+      <DataTemplate x:DataType="DataValidationErrors" x:Key="TooltipDataValidationErrorTemplate">
         <Panel Name="PART_InlineErrorTemplatePanel" Background="Transparent">
           <Panel.Styles>
             <Style Selector="Panel#PART_InlineErrorTemplatePanel">

src/Avalonia.Themes.Fluent/Controls/DatePicker.xaml

@@ -7,7 +7,8 @@
 
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="clr-namespace:System;assembly=netstandard">
+        xmlns:sys="clr-namespace:System;assembly=netstandard"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20">
       <DatePicker CornerRadius="10" />

src/Avalonia.Themes.Fluent/Controls/Expander.xaml

@@ -1,4 +1,6 @@
-<Styles xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+<Styles xmlns="https://github.com/avaloniaui" 
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Orientation="Vertical" Spacing="20" Width="350">
@@ -69,13 +71,13 @@
                         BorderThickness="{TemplateBinding BorderThickness}"
                         Content="{TemplateBinding Header}"
                         ContentTemplate="{TemplateBinding HeaderTemplate}"
-                        IsChecked="{Binding Path=IsExpanded, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
+                        IsChecked="{TemplateBinding IsExpanded, Mode=TwoWay}"
                         IsEnabled="{TemplateBinding IsEnabled}" />
           <Border x:Name="ExpanderContent"
                   Padding="{DynamicResource ExpanderContentPadding}"
                   Background="{DynamicResource ExpanderDropDownBackground}"
                   BorderBrush="{DynamicResource ExpanderDropDownBorderBrush}"
-                  IsVisible="{Binding Path=IsExpanded, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}">
+                  IsVisible="{TemplateBinding IsExpanded, Mode=TwoWay}">
             <ContentPresenter x:Name="PART_ContentPresenter"
                               HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                               VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"

src/Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml

@@ -142,7 +142,7 @@
                         <Rectangle Fill="{DynamicResource SystemControlHighlightAltBaseMediumLowBrush}" Height="1" Margin="0,5,0,0" DockPanel.Dock="Bottom"/>
                         <DockPanel Margin="4,0">
                             <Button Command="{Binding GoUp}" DockPanel.Dock="Left">
-                                <Path Data="M 0 7 L 7 0 L 14 7 M 7 0 L 7 16" Stroke="{Binding $parent[Button].Foreground}" StrokeThickness="1" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,1,0,-1"/>
+                                <Path Data="M 0 7 L 7 0 L 14 7 M 7 0 L 7 16" Stroke="{CompiledBinding $parent[Button].Foreground}" StrokeThickness="1" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,1,0,-1"/>
                             </Button>
                             <TextBox x:Name="Location" Text="{Binding Location}">
                                 <TextBox.KeyBindings>
@@ -321,4 +321,4 @@
     <Style Selector="dialogs|ManagedFileChooser /template/ UniformGrid#Finalize > Button /template/ ContentPresenter#PART_ContentPresenter">
             <Setter Property="HorizontalAlignment" Value="Stretch"/>
     </Style>
-</Styles>
+</Styles>

src/Avalonia.Themes.Fluent/Controls/MenuItem.xaml

@@ -1,7 +1,9 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:conv="clr-namespace:Avalonia.Controls.Converters;assembly=Avalonia.Controls"
-        xmlns:sys="clr-namespace:System;assembly=netstandard">
+        xmlns:sys="clr-namespace:System;assembly=netstandard"
+        x:DataType="MenuItem"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20"
             Width="400"
@@ -158,7 +160,7 @@
             </ContentPresenter>
             <Popup Name="PART_Popup"
                    WindowManagerAddShadowHint="False"
-                   MinWidth="{Binding Bounds.Width, RelativeSource={RelativeSource TemplatedParent}}"
+                   MinWidth="{ReflectionBinding Bounds.Width, RelativeSource={RelativeSource TemplatedParent}}"
                    IsLightDismissEnabled="True"
                    IsOpen="{TemplateBinding IsSubMenuOpen, Mode=TwoWay}"
                    OverlayInputPassThroughElement="{Binding $parent[Menu]}">

src/Avalonia.Themes.Fluent/Controls/NativeMenuBar.xaml

@@ -1,6 +1,7 @@
 <Style xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:Avalonia.Themes.Fluent"
+       x:CompileBindings="True"
        Selector="NativeMenuBar">
   <Style.Resources>
     <local:InverseBooleanValueConverter x:Key="AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter" Default="True"/>
@@ -11,7 +12,7 @@
         IsVisible="{Binding $parent[TopLevel].(NativeMenu.IsNativeMenuExported), Converter={StaticResource AvaloniaThemesDefaultNativeMenuBarInverseBooleanValueConverter}}"
         Items="{Binding $parent[TopLevel].(NativeMenu.Menu).Items}">
         <Menu.Styles>
-          <Style Selector="MenuItem">
+          <Style x:DataType="NativeMenuItem" Selector="MenuItem">
             <Setter Property="Header" Value="{Binding Header}"/>
             <Setter Property="InputGesture" Value="{Binding Gesture}"/>
             <Setter Property="Items" Value="{Binding Menu.Items}"/>

src/Avalonia.Themes.Fluent/Controls/ProgressBar.xaml

@@ -1,4 +1,6 @@
-<Styles xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+<Styles xmlns="https://github.com/avaloniaui" 
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="10">
@@ -29,8 +31,8 @@
                 <Border x:Name="IndeterminateProgressBarIndicator" CornerRadius="{TemplateBinding CornerRadius}" Margin="{TemplateBinding Padding}" Background="{TemplateBinding Foreground}" />
                 <Border x:Name="IndeterminateProgressBarIndicator2" CornerRadius="{TemplateBinding CornerRadius}" Margin="{TemplateBinding Padding}" Background="{TemplateBinding Foreground}" />
               </Panel>
-              <LayoutTransformControl x:Name="PART_LayoutTransformControl" HorizontalAlignment="Center" VerticalAlignment="Center" IsVisible="{Binding ShowProgressText, RelativeSource={RelativeSource TemplatedParent}}">
-                <TextBlock Foreground="{DynamicResource SystemControlForegroundBaseHighBrush}" Text="{Binding Value, RelativeSource={RelativeSource TemplatedParent}, StringFormat={}{0:0}%}" />
+              <LayoutTransformControl x:Name="PART_LayoutTransformControl" HorizontalAlignment="Center" VerticalAlignment="Center" IsVisible="{TemplateBinding ShowProgressText}">
+                <TextBlock Foreground="{DynamicResource SystemControlForegroundBaseHighBrush}" Text="{ReflectionBinding Value, RelativeSource={RelativeSource TemplatedParent}, StringFormat={}{0:0}%}" />
               </LayoutTransformControl>
             </Panel>
         </Border>

src/Avalonia.Themes.Fluent/Controls/TabItem.xaml

@@ -1,5 +1,6 @@
 <Styles xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">

src/Avalonia.Themes.Fluent/Controls/TabStripItem.xaml

@@ -1,5 +1,6 @@
 <Styles xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True">
   <Design.PreviewWith>
     <Border Padding="20">
       <StackPanel Spacing="20">

src/Avalonia.Themes.Fluent/Controls/TextBox.xaml

@@ -166,7 +166,7 @@
     <Setter Property="InnerRightContent">
       <Template>
         <ToggleButton Classes="passwordBoxRevealButton"
-                      IsChecked="{Binding $parent[TextBox].RevealPassword, Mode=TwoWay}" />
+                      IsChecked="{CompiledBinding $parent[TextBox].RevealPassword, Mode=TwoWay}" />
       </Template>
     </Setter>
   </Style>

src/Avalonia.Themes.Fluent/Controls/TimePicker.xaml

@@ -7,7 +7,8 @@
 
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        xmlns:sys="clr-namespace:System;assembly=netstandard">
+        xmlns:sys="clr-namespace:System;assembly=netstandard"
+        x:CompileBindings="True">
   <Styles.Resources>
     <x:Double x:Key="TimePickerFlyoutPresenterItemHeight">40</x:Double>
     <x:Double x:Key="TimePickerSpacerThemeWidth">1</x:Double>

src/Avalonia.Themes.Fluent/Controls/ToolTip.xaml

@@ -1,6 +1,7 @@
 <Styles xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"       
-        xmlns:sys="clr-namespace:System;assembly=netstandard">
+        xmlns:sys="clr-namespace:System;assembly=netstandard"
+        x:CompileBindings="True">
 
   <Design.PreviewWith>
     <Grid RowDefinitions="Auto,Auto"

src/Avalonia.Themes.Fluent/Controls/WindowNotificationManager.xaml

@@ -1,5 +1,7 @@
 <Styles xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:DataType="WindowNotificationManager"
+        x:CompileBindings="True">
   <Style Selector="WindowNotificationManager">
     <Setter Property="Margin" Value="0 0"/>    
     <Setter Property="Template">

src/Shared/RenderHelpers/ArcToHelper.cs → src/Avalonia.Visuals/Media/PreciseEllipticArcHelper.cs

@@ -1,5 +1,6 @@
 // Copyright © 2003-2004, Luc Maisonobe
 // 2015 - Alexey Rozanov <thehdotx@gmail.com> - Adaptations for Avalonia and oval center computations
+// 2022 - Alexey Rozanov <thehdotx@gmail.com> - Fix for arcs sometimes drawn in inverted order.
 // All rights reserved.
 // 
 // Redistribution and use in source and binary forms, with
@@ -49,12 +50,10 @@
 // Adapted from http://www.spaceroots.org/documents/ellipse/EllipticalArc.java
 
 using System;
-using Avalonia.Media;
-using Avalonia.Platform;
 
-namespace Avalonia.RenderHelpers
+namespace Avalonia.Media
 {
-    static class ArcToHelper
+    static class PreciseEllipticArcHelper
     {
         /// <summary>
         /// This class represents an elliptical arc on a 2D plane.
@@ -292,6 +291,8 @@ namespace Avalonia.RenderHelpers
             /// </summary>
             internal double G2;
 
+            public bool DrawInOppositeDirection { get; set; }
+
             /// <summary>
             /// Builds an elliptical arc composed of the full unit circle around (0,0)
             /// </summary>
@@ -850,7 +851,7 @@ namespace Avalonia.RenderHelpers
             /// Builds the arc outline using given StreamGeometryContext and default (max) Bezier curve degree and acceptable error of half a pixel (0.5)
             /// </summary>
             /// <param name="path">A StreamGeometryContext to output the path commands to</param>
-            public void BuildArc(IStreamGeometryContextImpl path)
+            public void BuildArc(StreamGeometryContext path)
             {
                 BuildArc(path, _maxDegree, _defaultFlatness, true);
             }
@@ -862,7 +863,7 @@ namespace Avalonia.RenderHelpers
             /// <param name="degree">degree of the Bezier curve to use</param>
             /// <param name="threshold">acceptable error</param>
             /// <param name="openNewFigure">if true, a new figure will be started in the specified StreamGeometryContext</param>
-            public void BuildArc(IStreamGeometryContextImpl path, int degree, double threshold, bool openNewFigure)
+            public void BuildArc(StreamGeometryContext path, int degree, double threshold, bool openNewFigure)
             {
                 if (degree < 1 || degree > _maxDegree)
                     throw new ArgumentException($"degree should be between {1} and {_maxDegree}", nameof(degree));
@@ -888,8 +889,18 @@ namespace Avalonia.RenderHelpers
                     }
                     n = n << 1;
                 }
-                dEta = (Eta2 - Eta1) / n;
-                etaB = Eta1;
+                if (!DrawInOppositeDirection)
+                {
+                    dEta = (Eta2 - Eta1) / n;
+                    etaB = Eta1;
+                }
+                else
+                {
+                    dEta = (Eta1 - Eta2) / n;
+                    etaB = Eta2;
+                }
+
+
                 double cosEtaB = Math.Cos(etaB);
                 double sinEtaB = Math.Sin(etaB);
                 double aCosEtaB = A * cosEtaB;
@@ -922,6 +933,7 @@ namespace Avalonia.RenderHelpers
                 */
 
                 //otherwise we're supposed to be already at the (xB,yB)
+                 
 
                 double t = Math.Tan(0.5 * dEta);
                 double alpha = Math.Sin(dEta) * (Math.Sqrt(4 + 3 * t * t) - 1) / 3;
@@ -1012,7 +1024,7 @@ namespace Avalonia.RenderHelpers
             /// <param name="theta">Ellipse theta (angle measured from the abscissa)</param>
             /// <param name="isLargeArc">Large Arc Indicator</param>
             /// <param name="clockwise">Clockwise direction flag</param>
-            public static void BuildArc(IStreamGeometryContextImpl path, Point p1, Point p2, Size size, double theta, bool isLargeArc, bool clockwise)
+            public static void BuildArc(StreamGeometryContext path, Point p1, Point p2, Size size, double theta, bool isLargeArc, bool clockwise)
             {
 
                 // var orthogonalizer = new RotateTransform(-theta);
@@ -1058,7 +1070,7 @@ namespace Avalonia.RenderHelpers
 
                 }
 
-                double multiplier = Math.Sqrt(numerator / denominator);
+                double multiplier = Math.Sqrt(Math.Abs(numerator / denominator));
                 Point mulVec = new Point(rx * p1S.Y / ry, -ry * p1S.X / rx);
 
                 int sign = (clockwise != isLargeArc) ? 1 : -1;
@@ -1104,9 +1116,16 @@ namespace Avalonia.RenderHelpers
                 // path.LineTo(c, true, true);
                 // path.LineTo(clockwise ? p1 : p2, true,true);
 
-                path.LineTo(clockwise ? p1 : p2);
                 var arc = new EllipticalArc(c.X, c.Y, rx, ry, theta, thetaStart, thetaEnd, false);
+
+                double ManhattanDistance(Point p1, Point p2) => Math.Abs(p1.X - p2.X) + Math.Abs(p1.Y - p2.Y);
+                if (ManhattanDistance(p2, new Point(arc.X2, arc.Y2)) > ManhattanDistance(p2, new Point(arc.X1, arc.Y1)))
+                {
+                    arc.DrawInOppositeDirection = true;
+                }
+
                 arc.BuildArc(path, arc._maxDegree, arc._defaultFlatness, false);
+                //path.LineTo(p2);
 
                 //uncomment this to draw a pie
                 //path.LineTo(c, true, true);
@@ -1136,9 +1155,9 @@ namespace Avalonia.RenderHelpers
             }
         }
 
-        public static void ArcTo(IStreamGeometryContextImpl streamGeometryContextImpl, Point currentPoint, Point point, Size size, double rotationAngle, bool isLargeArc, SweepDirection sweepDirection)
+        public static void ArcTo(StreamGeometryContext streamGeometryContextImpl, Point currentPoint, Point point, Size size, double rotationAngle, bool isLargeArc, SweepDirection sweepDirection)
         {
-            EllipticalArc.BuildArc(streamGeometryContextImpl, currentPoint, point, size, rotationAngle*Math.PI/180,
+            EllipticalArc.BuildArc(streamGeometryContextImpl, currentPoint, point, size, rotationAngle*(Math.PI/180),
                 isLargeArc,
                 sweepDirection == SweepDirection.Clockwise);
         }

src/Avalonia.Visuals/Media/StreamGeometryContext.cs

@@ -15,6 +15,8 @@ namespace Avalonia.Media
     {
         private readonly IStreamGeometryContextImpl _impl;
 
+        private Point _currentPoint;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="StreamGeometryContext"/> class.
         /// </summary>
@@ -47,6 +49,24 @@ namespace Avalonia.Media
         public void ArcTo(Point point, Size size, double rotationAngle, bool isLargeArc, SweepDirection sweepDirection)
         {
             _impl.ArcTo(point, size, rotationAngle, isLargeArc, sweepDirection);
+            _currentPoint = point;
+        }
+
+
+        /// <summary>
+        /// Draws an arc to the specified point using polylines, quadratic or cubic Bezier curves
+        /// Significantly more precise when drawing elliptic arcs with extreme width:height ratios.        
+        /// </summary>         
+        /// <param name="point">The destination point.</param>
+        /// <param name="size">The radii of an oval whose perimeter is used to draw the angle.</param>
+        /// <param name="rotationAngle">The rotation angle of the oval that specifies the curve.</param>
+        /// <param name="isLargeArc">true to draw the arc greater than 180 degrees; otherwise, false.</param>
+        /// <param name="sweepDirection">
+        /// A value that indicates whether the arc is drawn in the Clockwise or Counterclockwise direction.
+        /// </param>
+        public void PreciseArcTo(Point point, Size size, double rotationAngle, bool isLargeArc, SweepDirection sweepDirection)
+        {
+            PreciseEllipticArcHelper.ArcTo(this, _currentPoint, point, size, rotationAngle, isLargeArc, sweepDirection);
         }
 
         /// <summary>
@@ -57,6 +77,7 @@ namespace Avalonia.Media
         public void BeginFigure(Point startPoint, bool isFilled)
         {
             _impl.BeginFigure(startPoint, isFilled);
+            _currentPoint = startPoint;
         }
 
         /// <summary>
@@ -68,6 +89,7 @@ namespace Avalonia.Media
         public void CubicBezierTo(Point point1, Point point2, Point point3)
         {
             _impl.CubicBezierTo(point1, point2, point3);
+            _currentPoint = point3;
         }
 
         /// <summary>
@@ -78,6 +100,7 @@ namespace Avalonia.Media
         public void QuadraticBezierTo(Point control, Point endPoint)
         {
             _impl.QuadraticBezierTo(control, endPoint);
+            _currentPoint = endPoint;
         }
 
         /// <summary>
@@ -87,6 +110,7 @@ namespace Avalonia.Media
         public void LineTo(Point point)
         {
             _impl.LineTo(point);
+            _currentPoint = point;
         }
 
         /// <summary>

src/Shared/RenderHelpers/RenderHelpers.projitems

@@ -9,7 +9,6 @@
     <Import_RootNamespace>Avalonia.RenderHelpers</Import_RootNamespace>
   </PropertyGroup>
   <ItemGroup>
-    <Compile Include="$(MSBuildThisFileDirectory)ArcToHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)QuadBezierHelper.cs" />
   </ItemGroup>
 </Project>

tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs

@@ -1,9 +1,7 @@
 using System;
 using System.Collections.Generic;
-using System.ComponentModel;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Platform;
-using Avalonia.Threading;
 using Avalonia.UnitTests;
 using Moq;
 using Xunit;
@@ -57,7 +55,7 @@ namespace Avalonia.Controls.UnitTests
 
                 var hasExit = false;
 
-                lifetime.Exit += (s, e) => hasExit = true;
+                lifetime.Exit += (_, _) => hasExit = true;
 
                 var windowA = new Window();
 
@@ -91,7 +89,7 @@ namespace Avalonia.Controls.UnitTests
 
                 var hasExit = false;
 
-                lifetime.Exit += (s, e) => hasExit = true;
+                lifetime.Exit += (_, _) => hasExit = true;
 
                 var mainWindow = new Window();
 
@@ -119,7 +117,7 @@ namespace Avalonia.Controls.UnitTests
 
                 var hasExit = false;
 
-                lifetime.Exit += (s, e) => hasExit = true;
+                lifetime.Exit += (_, _) => hasExit = true;
 
                 var windowA = new Window();
 
@@ -226,7 +224,7 @@ namespace Avalonia.Controls.UnitTests
 
                 window.Show();
 
-                lifetime.ShutdownRequested += (s, e) =>
+                lifetime.ShutdownRequested += (_, e) =>
                 {
                     e.Cancel = true;
                     ++raised;
@@ -238,5 +236,171 @@ namespace Avalonia.Controls.UnitTests
                 Assert.Equal(new[] { window }, lifetime.Windows);
             }
         }
+        
+        [Fact]
+        public void MainWindow_Closed_Shutdown_Should_Be_Cancellable()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            using(var lifetime = new ClassicDesktopStyleApplicationLifetime())
+            {
+                lifetime.ShutdownMode = ShutdownMode.OnMainWindowClose;
+
+                var hasExit = false;
+
+                lifetime.Exit += (_, _) => hasExit = true;
+
+                var mainWindow = new Window();
+
+                mainWindow.Show();
+
+                lifetime.MainWindow = mainWindow;
+
+                var window = new Window();
+
+                window.Show();
+
+                var raised = 0;
+                
+                lifetime.ShutdownRequested += (_, e) =>
+                {
+                    e.Cancel = true;
+                    ++raised;
+                };
+
+                mainWindow.Close();
+                
+                Assert.Equal(1, raised);
+                Assert.False(hasExit);
+            }
+        }
+        
+        [Fact]
+        public void LastWindow_Closed_Shutdown_Should_Be_Cancellable()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            using(var lifetime = new ClassicDesktopStyleApplicationLifetime())
+            {
+                lifetime.ShutdownMode = ShutdownMode.OnLastWindowClose;
+
+                var hasExit = false;
+
+                lifetime.Exit += (_, _) => hasExit = true;
+
+                var windowA = new Window();
+
+                windowA.Show();
+
+                var windowB = new Window();
+
+                windowB.Show();
+                
+                var raised = 0;
+                
+                lifetime.ShutdownRequested += (_, e) =>
+                {
+                    e.Cancel = true;
+                    ++raised;
+                };
+
+                windowA.Close();
+
+                Assert.False(hasExit);
+
+                windowB.Close();
+
+                Assert.Equal(1, raised);
+                Assert.False(hasExit);
+            }
+        }
+        
+        [Fact]
+        public void TryShutdown_Cancellable_By_Preventing_Window_Close()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            using(var lifetime = new ClassicDesktopStyleApplicationLifetime())
+            {
+                var hasExit = false;
+
+                lifetime.Exit += (_, _) => hasExit = true;
+
+                var windowA = new Window();
+
+                windowA.Show();
+
+                var windowB = new Window();
+
+                windowB.Show();
+                
+                var raised = 0;
+
+                windowA.Closing += (_, e) =>
+                {
+                    e.Cancel = true;
+                    ++raised;
+                };
+
+                lifetime.TryShutdown();
+
+                Assert.Equal(1, raised);
+                Assert.False(hasExit);
+            }
+        }
+        
+        [Fact]
+        public void Shutdown_NotCancellable_By_Preventing_Window_Close()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            using(var lifetime = new ClassicDesktopStyleApplicationLifetime())
+            {
+                var hasExit = false;
+
+                lifetime.Exit += (_, _) => hasExit = true;
+
+                var windowA = new Window();
+
+                windowA.Show();
+
+                var windowB = new Window();
+
+                windowB.Show();
+                
+                var raised = 0;
+
+                windowA.Closing += (_, e) =>
+                {
+                    e.Cancel = true;
+                    ++raised;
+                };
+
+                lifetime.Shutdown();
+
+                Assert.Equal(1, raised);
+                Assert.True(hasExit);
+            }
+        }
+        
+        [Fact]
+        public void Shutdown_Doesnt_Raise_Shutdown_Requested()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            using(var lifetime = new ClassicDesktopStyleApplicationLifetime())
+            {
+                var hasExit = false;
+
+                lifetime.Exit += (_, _) => hasExit = true;
+                
+                var raised = 0;
+
+                lifetime.ShutdownRequested += (_, _) =>
+                {
+                    ++raised;
+                };
+
+                lifetime.Shutdown();
+
+                Assert.Equal(0, raised);
+                Assert.True(hasExit);
+            }
+        }
     }
 }

tests/Avalonia.RenderTests/Media/StreamGeometryTests.cs

@@ -0,0 +1,56 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using Avalonia.Controls.Shapes;
+using Avalonia.Media;
+using Avalonia.Media.Imaging;
+using Xunit;
+
+#if AVALONIA_SKIA
+namespace Avalonia.Skia.RenderTests
+#else
+namespace Avalonia.Direct2D1.RenderTests.Media
+#endif
+{
+    public class StreamGeometryTests : TestBase
+    {
+        public StreamGeometryTests()
+            : base(@"Media\StreamGeometry")
+        {
+        }
+         
+        [Fact]
+        public async Task PreciseEllipticArc_Produces_Valid_Arcs_In_All_Directions()
+        {
+            var grid = new Avalonia.Controls.Primitives.UniformGrid() { Columns = 2, Rows = 4, Width = 320, Height = 400 };
+            foreach (var sweepDirection in new[] { SweepDirection.Clockwise, SweepDirection.CounterClockwise })
+                foreach (var isLargeArc in new[] { false, true })
+                    foreach (var isPrecise in new[] { false, true })
+                    {
+                        Point Pt(double x, double y) => new Point(x, y);
+                        Size Sz(double w, double h) => new Size(w, h);
+                        var streamGeometry = new StreamGeometry();
+                        using (var context = streamGeometry.Open())
+                        {
+                            context.BeginFigure(Pt(20, 20), true);
+
+                            if(isPrecise)
+                                context.PreciseArcTo(Pt(40, 40), Sz(20, 20), 0, isLargeArc, sweepDirection);
+                            else
+                                context.ArcTo(Pt(40, 40), Sz(20, 20), 0, isLargeArc, sweepDirection);
+                            context.LineTo(Pt(40, 20));
+                            context.LineTo(Pt(20, 20));
+                            context.EndFigure(true);
+                        }
+                        var pathShape = new Avalonia.Controls.Shapes.Path();
+                        pathShape.Data = streamGeometry;
+                        pathShape.Stroke = new SolidColorBrush(Colors.CornflowerBlue);
+                        pathShape.Fill = new SolidColorBrush(Colors.Gold);
+                        pathShape.StrokeThickness = 2;
+                        pathShape.Margin = new Thickness(20);
+                        grid.Children.Add(pathShape);
+                    }
+            await RenderToFile(grid);
+        }
+    }
+}