OnUIThread-Refactor and a few improvements

src/Caliburn.Micro.Avalonia.Tests/ScopeNamingRouteTests.cs

@@ -25,8 +25,7 @@ public void CorrectlyGetsAddedHop()
             var d1 = new AvaloniaObject();
             var d2 = new AvaloniaObject();
             route.AddHop(d1, d2);
-            AvaloniaObject target;
-            var result = route.TryGetHop(d1, out target);
+            var result = route.TryGetHop(d1, out AvaloniaObject target);
             Assert.True(result);
             Assert.Same(d2, target);
         }
@@ -52,9 +51,8 @@ public void GetsAllHopsAdded()
             };
 
             var source = d1;
-            AvaloniaObject target;
 
-            while (route.TryGetHop(source, out target))
+            while (route.TryGetHop(source, out AvaloniaObject target))
             {
                 all.Remove(target);
                 source = target;

src/Caliburn.Micro.Avalonia.Tests/ViewModelLocatorTests.cs

@@ -56,7 +56,7 @@ public void ConfigureTypeMappingsShouldThrowWhenDefaultSubNamespaceForViewsIsNul
 
 
         [Fact]
-        public void COnfigureTypeMappingsWithDefaultValuesShouldNotThrow()
+        public void ConfigureTypeMappingsWithDefaultValuesShouldNotThrow()
         {
             var typeMappingConfiguration = new TypeMappingConfiguration();
 

src/Caliburn.Micro.Core.Tests/IoCTests.cs

@@ -61,7 +61,7 @@ public void A_not_initialized_GetInstance_throws_an_InvalidOperationException()
         }
 
         [Fact]
-        public void A_null_GetInstance_throws_a_NullRefrenceException()
+        public void A_null_GetInstance_throws_a_NullReferenceException()
         {
             using (IoCReset.Create())
             {

src/Caliburn.Micro.Core.Tests/ScreenExtentionTests.cs

@@ -12,20 +12,10 @@ public async Task Screen_ConductWithTests()
         {
             var root = new Screen();
 
-            var child1 = new StateScreen
-            {
-                DisplayName = "screen1"
-            };
+            var child1 = new StateScreen { DisplayName = "screen1" };
             // simulate a long deactivation process 
-            var child2 = new StateScreen(TimeSpan.FromSeconds(3))
-            {
-                DisplayName = "screen2"
-            };
-
-            var child3 = new StateScreen()
-            {
-                DisplayName = "screen3"
-            };
+            var child2 = new StateScreen(TimeSpan.FromSeconds(3)) { DisplayName = "screen2" };
+            var child3 = new StateScreen() { DisplayName = "screen3" };
 
             child1.ConductWith(root);
             child2.ConductWith(root);
@@ -49,20 +39,13 @@ public async Task Conductor_ConductWithTests()
         {
             var root = new Conductor<StateScreen>.Collection.AllActive();
 
-            var child1 = new StateScreen
-            {
-                DisplayName = "screen1"
-            };
+            var child1 = new StateScreen { DisplayName = "screen1" };
             var child2 = new StateScreen(TimeSpan.FromSeconds(3))
             {
                 DisplayName = "screen2",
                 IsClosable = false,
             };
-
-            var child3 = new StateScreen()
-            {
-                DisplayName = "screen3"
-            };
+            var child3 = new StateScreen() { DisplayName = "screen3" };
 
             root.Items.Add(child1);
             root.Items.Add(child2);
@@ -81,8 +64,10 @@ public async Task Conductor_ConductWithTests()
             Assert.True(child3.IsClosed, "child 3 should be closed");
         }
 
-        class StateScreen : Screen
+        private sealed class StateScreen : Screen
         {
+            private readonly TimeSpan? deactivationDelay;
+
             public StateScreen()
             {
             }
@@ -93,7 +78,9 @@ public StateScreen(TimeSpan? deactivationDelay)
             }
 
             public bool WasActivated { get; private set; }
+
             public bool IsClosed { get; private set; }
+
             public bool IsClosable { get; set; }
 
             public override Task<bool> CanCloseAsync(CancellationToken cancellationToken = default)
@@ -129,7 +116,7 @@ protected override async Task OnActivatedAsync(CancellationToken cancellationTok
                 IsClosable = false;
             }
 
-            protected override async Task OnDeactivateAsync(bool close, CancellationToken cancellationToken = default(CancellationToken))
+            protected override async Task OnDeactivateAsync(bool close, CancellationToken cancellationToken = default)
             {
                 await base.OnDeactivateAsync(close, cancellationToken);
 
@@ -140,8 +127,6 @@ protected override async Task OnActivatedAsync(CancellationToken cancellationTok
 
                 IsClosed = close;
             }
-
-            private readonly TimeSpan? deactivationDelay;
         }
     }
 }

src/Caliburn.Micro.Core.Tests/SimpleContainerTests.cs

@@ -89,7 +89,7 @@ public void Null_is_returned_when_no_instance_is_found()
     public class SimpleContainerRegisteringInstances
     {
         [Fact]
-        public void Instances_registed_Singleton_return_the_same_instance_for_each_call()
+        public void Instances_registered_Singleton_return_the_same_instance_for_each_call()
         {
             var container = new SimpleContainer();
             container.Singleton<object>();
@@ -146,7 +146,7 @@ public void Container_Finds_Single_Constructor()
 
         public class SingleNonEmptyConstructorType
         {
-            public SingleNonEmptyConstructorType(SimpleContainer_Find_Constructor.SingleEmptyConstructorType type)
+            public SingleNonEmptyConstructorType(SingleEmptyConstructorType type)
             {
             }
         }
@@ -165,18 +165,18 @@ public class SingleIntConstructor
 
             public SingleIntConstructor(int x)
             {
-                this.Value = x;
+                Value = x;
             }
         }
 
         [Fact]
         public void Container_SingleIntConstructor()
         {
-            var container = new SimpleContainer();
-            container.Singleton<SingleIntConstructor>();
-            container.RegisterInstance(typeof(int), "x", 4);
-            var inst = (SingleIntConstructor)container.GetInstance(typeof(SingleIntConstructor), null);
-            Assert.Equal(4, inst.Value);
+            var sut = new SimpleContainer();
+            sut.Singleton<SingleIntConstructor>();
+            sut.RegisterInstance(typeof(int), "x", 4);
+            var result = (SingleIntConstructor)sut.GetInstance(typeof(SingleIntConstructor), null);
+            Assert.Equal(4, result.Value);
         }
 
         public class TwoConstructors
@@ -185,7 +185,7 @@ public class TwoConstructors
 
             public TwoConstructors()
             {
-                this.Value = 42;
+                Value = 42;
             }
 
             public TwoConstructors(int value)
@@ -197,20 +197,20 @@ public TwoConstructors(int value)
         [Fact]
         public void Container_ChooseConstructorWithRegisteredParameter()
         {
-            var container = new SimpleContainer();
-            container.Singleton<TwoConstructors>();
-            container.RegisterInstance(typeof(int), null, 23);
-            var inst = (TwoConstructors)container.GetInstance(typeof(TwoConstructors), null);
-            Assert.Equal(23, inst.Value);
+            var sut = new SimpleContainer();
+            sut.Singleton<TwoConstructors>();
+            sut.RegisterInstance(typeof(int), null, 23);
+            var result = (TwoConstructors)sut.GetInstance(typeof(TwoConstructors), null);
+            Assert.Equal(23, result.Value);
         }
 
         [Fact]
         public void Container_ChooseEmptyConstructorWithoutRegisteredParameter()
         {
-            var container = new SimpleContainer();
-            container.Singleton<TwoConstructors>();
-            var inst = (TwoConstructors)container.GetInstance(typeof(TwoConstructors), null);
-            Assert.Equal(42, inst.Value);
+            var sut = new SimpleContainer();
+            sut.Singleton<TwoConstructors>();
+            var result = (TwoConstructors)sut.GetInstance(typeof(TwoConstructors), null);
+            Assert.Equal(42, result.Value);
         }
     }
 

src/Caliburn.Micro.Core/AsyncEventHandler.cs

@@ -10,8 +10,6 @@ namespace Caliburn.Micro
     /// <param name="sender">The source of the event.</param>
     /// <param name="e">An object that contains the event data.</param>
     /// <returns>A task that represents the asynchronous operation.</returns>
-    public delegate Task AsyncEventHandler<TEventArgs>(
-        object sender,
-        TEventArgs e)
+    public delegate Task AsyncEventHandler<TEventArgs>(object sender, TEventArgs e)
         where TEventArgs : EventArgs;
 }

src/Caliburn.Micro.Core/BindableCollection.cs

@@ -43,14 +43,7 @@ public virtual void NotifyOfPropertyChange(string propertyName)
         {
             if (IsNotifying)
             {
-                if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-                {
-                    OnUIThread(() => OnPropertyChanged(new PropertyChangedEventArgs(propertyName)));
-                }
-                else
-                {
-                    OnPropertyChanged(new PropertyChangedEventArgs(propertyName));
-                }
+                Execute.DispatchIfRequired(() => OnPropertyChanged(new PropertyChangedEventArgs(propertyName)));
             }
         }
 
@@ -59,21 +52,12 @@ public virtual void NotifyOfPropertyChange(string propertyName)
         /// </summary>
         public void Refresh()
         {
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(() =>
-                {
-                    OnPropertyChanged(new PropertyChangedEventArgs("Count"));
-                    OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
-                    OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
-                });
-            }
-            else
+            Execute.DispatchIfRequired(() =>
             {
                 OnPropertyChanged(new PropertyChangedEventArgs("Count"));
                 OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
                 OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
-            }
+            });
         }
 
         /// <summary>
@@ -83,14 +67,7 @@ public void Refresh()
         /// <param name = "item">The item to be inserted.</param>
         protected override sealed void InsertItem(int index, T item)
         {
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(() => InsertItemBase(index, item));
-            }
-            else
-            {
-                InsertItemBase(index, item);
-            }
+            Execute.DispatchIfRequired(() => InsertItemBase(index, item));
         }
 
         /// <summary>
@@ -113,14 +90,7 @@ protected virtual void InsertItemBase(int index, T item)
         /// <param name = "item">The item to set.</param>
         protected override sealed void SetItem(int index, T item)
         {
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(() => SetItemBase(index, item));
-            }
-            else
-            {
-                SetItemBase(index, item);
-            }
+            Execute.DispatchIfRequired(() => SetItemBase(index, item));
         }
 
         /// <summary>
@@ -142,14 +112,7 @@ protected virtual void SetItemBase(int index, T item)
         /// <param name = "index">The position used to identify the item to remove.</param>
         protected override sealed void RemoveItem(int index)
         {
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(() => RemoveItemBase(index));
-            }
-            else
-            {
-                RemoveItemBase(index);
-            }
+            Execute.DispatchIfRequired(() => RemoveItemBase(index));
         }
 
         /// <summary>
@@ -223,21 +186,15 @@ void AddRange()
                     InsertItemBase(index, item);
                     index++;
                 }
+
                 IsNotifying = previousNotificationSetting;
 
                 OnPropertyChanged(new PropertyChangedEventArgs("Count"));
                 OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
                 OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
             }
 
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(AddRange);
-            }
-            else
-            {
-                AddRange();
-            }
+            Execute.DispatchIfRequired(AddRange);
         }
 
         /// <summary>
@@ -258,28 +215,22 @@ void RemoveRange()
                         RemoveItemBase(index);
                     }
                 }
+
                 IsNotifying = previousNotificationSetting;
 
                 OnPropertyChanged(new PropertyChangedEventArgs("Count"));
                 OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
                 OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
             }
 
-            if (PlatformProvider.Current.PropertyChangeNotificationsOnUIThread)
-            {
-                OnUIThread(RemoveRange);
-            }
-            else
-            {
-                RemoveRange();
-            }
+            Execute.DispatchIfRequired(RemoveRange);
         }
 
         /// <summary>
         /// Executes the given action on the UI thread
         /// </summary>
-        /// <remarks>An extension point for subclasses to customise how property change notifications are handled.</remarks>
+        /// <remarks>An extension point for subclasses to customize how property change notifications are handled.</remarks>
         /// <param name="action"></param>
-        protected virtual void OnUIThread(System.Action action) => action.OnUIThread();
+        protected virtual void OnUIThread(Action action) => action.OnUIThread();
     }
 }

src/Caliburn.Micro.Core/Conductor.cs

@@ -52,7 +52,7 @@ public override async Task DeactivateItemAsync(T item, bool close, CancellationT
 
             if (closeResult.CloseCanOccur)
             {
-                await ChangeActiveItemAsync(default(T), close, cancellationToken);
+                await ChangeActiveItemAsync(default, close, cancellationToken);
             }
         }
 

src/Caliburn.Micro.Core/ConductorBase.cs

@@ -20,7 +20,7 @@ public abstract class ConductorBase<T> : Screen, IConductor, IParent<T> where T
         /// <value>The close strategy.</value>
         public ICloseStrategy<T> CloseStrategy
         {
-            get => _closeStrategy ?? (_closeStrategy = new DefaultCloseStrategy<T>());
+            get => _closeStrategy ??= new DefaultCloseStrategy<T>();
             set => _closeStrategy = value;
         }
 
@@ -91,7 +91,7 @@ protected virtual void OnActivationProcessed(T item, bool success)
         /// <returns>The item to be activated.</returns>
         protected virtual T EnsureItem(T newItem)
         {
-            if (newItem is IChild node && !object.ReferenceEquals(node.Parent, this))
+            if (newItem is IChild node && !ReferenceEquals(node.Parent, this))
                 node.Parent = this;
 
             return newItem;

src/Caliburn.Micro.Core/ConductorBaseWithActiveItem.cs

@@ -7,7 +7,8 @@ namespace Caliburn.Micro
     /// A base class for various implementations of <see cref="IConductor"/> that maintain an active item.
     /// </summary>
     /// <typeparam name="T">The type that is being conducted.</typeparam>
-    public abstract class ConductorBaseWithActiveItem<T> : ConductorBase<T>, IConductActiveItem where T : class
+    public abstract class ConductorBaseWithActiveItem<T> : ConductorBase<T>, IConductActiveItem
+        where T : class
     {
         private T _activeItem;