Merge pull request #6310 from AvaloniaUI/features/win32-allow-cancel-app-shutdown

Features/win32 allow cancel app shutdown
# Conflicts:
#	src/Avalonia.Controls/ApiCompatBaseline.txt

src/Avalonia.Controls/ApiCompatBaseline.txt

@@ -1,9 +1,9 @@
 Compat issues with assembly Avalonia.Controls:
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.INativeMenuExporterEventsImplBridge.RaiseClosed()' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.INativeMenuExporterEventsImplBridge.RaiseOpening()' is present in the implementation but not in the contract.
-InterfacesShouldHaveSameMembers : Interface member 'public System.EventHandler<System.ComponentModel.CancelEventArgs> 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<System.ComponentModel.CancelEventArgs>)' is present in the implementation but not in the contract.
-InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.ApplicationLifetimes.IClassicDesktopStyleApplicationLifetime.remove_ShutdownRequested(System.EventHandler<System.ComponentModel.CancelEventArgs>)' is present in the implementation but not in the contract.
+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.
 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.
 MembersMustExist : Member 'public void Avalonia.Controls.Embedding.Offscreen.OffscreenTopLevelImplBase.SetCursor(Avalonia.Platform.IPlatformHandle)' does not exist in the implementation but it does exist in the contract.

src/Avalonia.Controls/ApplicationLifetimes/ClassicDesktopStyleApplicationLifetime.cs

@@ -48,7 +48,7 @@ namespace Avalonia.Controls.ApplicationLifetimes
         public event EventHandler<ControlledApplicationLifetimeStartupEventArgs> Startup;
 
         /// <inheritdoc/>
-        public event EventHandler<CancelEventArgs> ShutdownRequested;
+        public event EventHandler<ShutdownRequestedEventArgs> ShutdownRequested;
 
         /// <inheritdoc/>
         public event EventHandler<ControlledApplicationLifetimeExitEventArgs> Exit;
@@ -134,7 +134,7 @@ namespace Avalonia.Controls.ApplicationLifetimes
                 _activeLifetime = null;
         }
         
-        private void OnShutdownRequested(object sender, CancelEventArgs e)
+        private void OnShutdownRequested(object sender, ShutdownRequestedEventArgs e)
         {
             ShutdownRequested?.Invoke(this, e);
 

src/Avalonia.Controls/ApplicationLifetimes/IClassicDesktopStyleApplicationLifetime.cs

@@ -37,14 +37,21 @@ namespace Avalonia.Controls.ApplicationLifetimes
         IReadOnlyList<Window> Windows { get; }
 
         /// <summary>
-        /// Raised by the platform when a shutdown is requested.
+        /// Raised by the platform when an application shutdown is requested.
         /// </summary>
         /// <remarks>
-        /// Raised on on OSX via the Quit menu or right-clicking on the application icon and selecting Quit. This event
-        /// provides a first-chance to cancel application shutdown; if shutdown is not canceled at this point the application
+        /// Application Shutdown can be requested for various reasons like OS shutdown.
+        /// 
+        /// On Windows this will be called when an OS Session (logout or shutdown) terminates. Cancelling the eventargs will 
+        /// block OS shutdown.
+        /// 
+        /// On OSX this has the same behavior as on Windows and in addition:
+        /// This event is raised via the Quit menu or right-clicking on the application icon and selecting Quit. 
+        /// 
+        /// This event provides a first-chance to cancel application shutdown; if shutdown is not canceled at this point the application
         /// will try to close each non-owned open window, invoking the <see cref="Window.Closing"/> event on each and allowing
-        /// each window to cancel the shutdown.
+        /// each window to cancel the shutdown of the application. Windows cannot however prevent OS shutdown.
         /// </remarks>
-        event EventHandler<CancelEventArgs> ShutdownRequested;
+        event EventHandler<ShutdownRequestedEventArgs> ShutdownRequested;
     }
 }

src/Avalonia.Controls/ApplicationLifetimes/ShutdownRequestedEventArgs.cs

@@ -0,0 +1,9 @@
+using System.ComponentModel;
+
+namespace Avalonia.Controls.ApplicationLifetimes
+{
+    public class ShutdownRequestedEventArgs : CancelEventArgs
+    {
+
+    }
+}

src/Avalonia.Controls/Platform/IPlatformLifetimeEventsImpl.cs

@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using Avalonia.Controls.ApplicationLifetimes;
 
 namespace Avalonia.Platform
 {
@@ -11,6 +12,6 @@ namespace Avalonia.Platform
         /// <remarks>
         /// Raised on on OSX via the Quit menu or right-clicking on the application icon and selecting Quit.
         /// </remarks>
-        event EventHandler<CancelEventArgs> ShutdownRequested;
+        event EventHandler<ShutdownRequestedEventArgs> ShutdownRequested;
     }
 }

src/Avalonia.Native/AvaloniaNativeApplicationPlatform.cs

@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Native.Interop;
 using Avalonia.Platform;
 
@@ -7,7 +8,7 @@ namespace Avalonia.Native
 {
     internal class AvaloniaNativeApplicationPlatform : CallbackBase, IAvnApplicationEvents, IPlatformLifetimeEventsImpl
     {
-        public event EventHandler<CancelEventArgs> ShutdownRequested;
+        public event EventHandler<ShutdownRequestedEventArgs> ShutdownRequested;
         
         void IAvnApplicationEvents.FilesOpened(IAvnStringArray urls)
         {
@@ -17,7 +18,7 @@ namespace Avalonia.Native
         public int TryShutdown()
         {
             if (ShutdownRequested is null) return 1;
-            var e = new CancelEventArgs();
+            var e = new ShutdownRequestedEventArgs();
             ShutdownRequested(this, e);
             return (!e.Cancel).AsComBool();
         }

src/Windows/Avalonia.Win32/Win32Platform.cs

@@ -6,18 +6,16 @@ using System.IO;
 using System.Reactive.Disposables;
 using System.Runtime.InteropServices;
 using System.Threading;
-using Avalonia.Animation;
 using Avalonia.Controls;
+using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Controls.Platform;
 using Avalonia.Input;
 using Avalonia.Input.Platform;
 using Avalonia.OpenGL;
-using Avalonia.OpenGL.Egl;
 using Avalonia.Platform;
 using Avalonia.Rendering;
 using Avalonia.Threading;
 using Avalonia.Utilities;
-using Avalonia.Win32;
 using Avalonia.Win32.Input;
 using Avalonia.Win32.Interop;
 using static Avalonia.Win32.Interop.UnmanagedMethods;
@@ -65,7 +63,7 @@ namespace Avalonia
 
 namespace Avalonia.Win32
 {
-    class Win32Platform : IPlatformThreadingInterface, IPlatformSettings, IWindowingPlatform, IPlatformIconLoader
+    class Win32Platform : IPlatformThreadingInterface, IPlatformSettings, IWindowingPlatform, IPlatformIconLoader, IPlatformLifetimeEventsImpl
     {
         private static readonly Win32Platform s_instance = new Win32Platform();
         private static Thread _uiThread;
@@ -115,7 +113,8 @@ namespace Avalonia.Win32
                 .Bind<PlatformHotkeyConfiguration>().ToSingleton<PlatformHotkeyConfiguration>()
                 .Bind<IPlatformIconLoader>().ToConstant(s_instance)
                 .Bind<NonPumpingLockHelper.IHelperImpl>().ToConstant(new NonPumpingSyncContext.HelperImpl())
-                .Bind<IMountedVolumeInfoProvider>().ToConstant(new WindowsMountedVolumeInfoProvider());
+                .Bind<IMountedVolumeInfoProvider>().ToConstant(new WindowsMountedVolumeInfoProvider())
+                .Bind<IPlatformLifetimeEventsImpl>().ToConstant(s_instance);
 
             Win32GlManager.Initialize();
 
@@ -200,6 +199,8 @@ namespace Avalonia.Win32
 
         public event Action<DispatcherPriority?> Signaled;
 
+        public event EventHandler<ShutdownRequestedEventArgs> ShutdownRequested;
+
         [SuppressMessage("Microsoft.StyleCop.CSharp.NamingRules", "SA1305:FieldNamesMustNotUseHungarianNotation", Justification = "Using Win32 naming for consistency.")]
         private IntPtr WndProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam)
         {
@@ -207,6 +208,22 @@ namespace Avalonia.Win32
             {
                 Signaled?.Invoke(null);
             }
+
+            if(msg == (uint)WindowsMessage.WM_QUERYENDSESSION)
+            {
+                if (ShutdownRequested != null)
+                {
+                    var e = new ShutdownRequestedEventArgs();
+
+                    ShutdownRequested(this, e);
+
+                    if(e.Cancel)
+                    {
+                        return IntPtr.Zero;
+                    }
+                }
+            }
+
             return UnmanagedMethods.DefWindowProc(hWnd, msg, wParam, lParam);
         }
 

tests/Avalonia.Controls.UnitTests/DesktopStyleApplicationLifetimeTests.cs

@@ -232,7 +232,7 @@ namespace Avalonia.Controls.UnitTests
                     ++raised;
                 };
 
-                lifetimeEvents.Raise(x => x.ShutdownRequested += null, new CancelEventArgs());
+                lifetimeEvents.Raise(x => x.ShutdownRequested += null, new ShutdownRequestedEventArgs());
 
                 Assert.Equal(1, raised);
                 Assert.Equal(new[] { window }, lifetime.Windows);