allow to handle HadwareButtons.BackPressed in WPA81

nuget/Caliburn.Light.nuspec

@@ -3,7 +3,7 @@
   <metadata>
     <id>Caliburn.Light</id>
     <title>Caliburn.Light</title>
-    <version>1.2.2</version>
+    <version>1.2.3</version>
     <authors>Thomas Ibel</authors>
     <description>The magic-free Caliburn.Micro, a powerful framework designed for building applications across all XAML platforms.</description>
     <language>en-US</language>

src/Caliburn.Xaml.Universal/Services/FrameAdapter.cs

@@ -6,6 +6,9 @@
 using Windows.UI.Xaml;
 using Windows.UI.Xaml.Controls;
 using Windows.UI.Xaml.Navigation;
+#if WINDOWS_PHONE_APP
+using Windows.Phone.UI.Input;
+#endif
 
 namespace Caliburn.Light
 {
@@ -19,7 +22,6 @@ public class FrameAdapter : INavigationService
         private const string ParameterKey = "ParameterKey";
 
         private readonly Frame _frame;
-        private event NavigatingCancelEventHandler ExternalNavigatingHandler = delegate { };
         private object _currentParameter;
 
         /// <summary>
@@ -34,8 +36,8 @@ public FrameAdapter(Frame frame)
             _frame.Navigated += OnNavigated;
 
 #if WINDOWS_PHONE_APP
-            _frame.Loaded += (sender, args) => { Windows.Phone.UI.Input.HardwareButtons.BackPressed += OnHardwareBackPressed; };
-            _frame.Unloaded += (sender, args) => { Windows.Phone.UI.Input.HardwareButtons.BackPressed -= OnHardwareBackPressed; };
+            _frame.Loaded += (sender, args) => { HardwareButtons.BackPressed += OnHardwareBackPressed; };
+            _frame.Unloaded += (sender, args) => { HardwareButtons.BackPressed -= OnHardwareBackPressed; };
 #endif
         }
 
@@ -46,7 +48,9 @@ public FrameAdapter(Frame frame)
         /// <param name="e"> The event args. </param>
         protected virtual void OnNavigating(object sender, NavigatingCancelEventArgs e)
         {
-            ExternalNavigatingHandler(sender, e);
+            var handler = Navigating;
+            if (handler != null)
+                handler(sender, e);
 
             if (e.Cancel)
                 return;
@@ -85,7 +89,6 @@ protected virtual void OnNavigating(object sender, NavigatingCancelEventArgs e)
         /// <param name="e"> The event args. </param>
         protected virtual void OnNavigated(object sender, NavigationEventArgs e)
         {
-
             if (e.Content == null)
                 return;
 
@@ -139,32 +142,25 @@ protected virtual void TryInjectParameters(object viewModel, object parameter)
             {
                 var uri = new Uri((string) parameter);
 
-                if (!String.IsNullOrEmpty(uri.Query))
+                if (!string.IsNullOrEmpty(uri.Query))
                 {
                     var decorder = new WwwFormUrlDecoder(uri.Query);
 
                     foreach (var pair in decorder)
                     {
                         var property = viewModelType.GetRuntimeProperty(pair.Name);
-
-                        if (property == null)
-                        {
-                            continue;
-                        }
+                        if (property == null) continue;
 
                         property.SetValue(viewModel,
-                            ParameterBinder.CoerceValue(property.PropertyType, pair.Value, null));
+                            ParameterBinder.CoerceValue(property.PropertyType, pair.Value));
                     }
                 }
             }
             else
             {
                 var property = viewModelType.GetRuntimeProperty("Parameter");
-
-                if (property == null)
-                    return;
-
-                property.SetValue(viewModel, ParameterBinder.CoerceValue(property.PropertyType, parameter, null));
+                if (property == null) return;
+                property.SetValue(viewModel, ParameterBinder.CoerceValue(property.PropertyType, parameter));
             }
         }
 
@@ -190,11 +186,7 @@ public event NavigatedEventHandler Navigated
         /// <summary>
         ///   Raised prior to navigation.
         /// </summary>
-        public event NavigatingCancelEventHandler Navigating
-        {
-            add { ExternalNavigatingHandler += value; }
-            remove { ExternalNavigatingHandler -= value; }
-        }
+        public event NavigatingCancelEventHandler Navigating;
 
         /// <summary>
         ///   Raised when navigation fails.
@@ -332,30 +324,45 @@ public bool ResumeState()
                 ? container.Values[ParameterKey]
                 : null;
 
-            if (String.IsNullOrEmpty(frameState))
+            if (string.IsNullOrEmpty(frameState))
                 return false;
 
             _frame.SetNavigationState(frameState);
 
             var view = _frame.Content as Page;
-            if (view == null)
-            {
-                return false;
-            }
+            if (view == null) return false;
 
             BindViewModel(view);
 
             if (!ReferenceEquals(Window.Current.Content, _frame))
                 Window.Current.Content = _frame;
 
             Window.Current.Activate();
-
             return true;
         }
 
 #if WINDOWS_PHONE_APP
-        private void OnHardwareBackPressed(object sender, Windows.Phone.UI.Input.BackPressedEventArgs e)
+        /// <summary>
+        /// Occurs when the user presses the hardware Back button.
+        /// </summary>
+        public event EventHandler<BackPressedEventArgs> BackPressed;
+
+        /// <summary>
+        ///  Occurs when the user presses the hardware Back button. Allows the handlers to cancel the default behavior.
+        /// </summary>
+        /// <param name="e">The event arguments</param>
+        protected virtual void OnBackPressed(BackPressedEventArgs e)
         {
+            var handler = BackPressed;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        private void OnHardwareBackPressed(object sender, BackPressedEventArgs e)
+        {
+            OnBackPressed(e);
+            if (e.Handled) return;
+
             if (CanGoBack)
             {
                 e.Handled = true;
@@ -370,4 +377,4 @@ private static ApplicationDataContainer GetSettingsContainer()
                 ApplicationDataCreateDisposition.Always);
         }
     }
-}
+}

src/Caliburn.Xaml.Universal/Services/INavigationService.cs

@@ -1,6 +1,9 @@
 using System;
 using System.Collections.Generic;
 using Windows.UI.Xaml.Navigation;
+#if WINDOWS_PHONE_APP
+using Windows.Phone.UI.Input;
+#endif
 
 namespace Caliburn.Light
 {
@@ -77,6 +80,13 @@ public interface INavigationService
         /// </summary>
         IList<PageStackEntry> ForwardStack { get; }
 
+#if WINDOWS_PHONE_APP
+        /// <summary>
+        /// Occurs when the user presses the hardware Back button.
+        /// </summary>
+        event EventHandler<BackPressedEventArgs> BackPressed;
+#endif
+
         /// <summary>
         /// Stores the frame navigation state in local settings if it can.
         /// </summary>

src/Caliburn.Xaml.WP8/Services/FrameAdapter.cs

@@ -13,7 +13,6 @@ namespace Caliburn.Light
     public class FrameAdapter : INavigationService
     {
         private readonly Frame _frame;
-        private NavigatingCancelEventHandler _externalNavigatingHandler;
 
         /// <summary>
         ///   Creates an instance of <see cref="FrameAdapter" />
@@ -33,7 +32,7 @@ public FrameAdapter(Frame frame)
         /// <param name="e"> The event args. </param>
         protected virtual void OnNavigating(object sender, NavigatingCancelEventArgs e)
         {
-            var handler = _externalNavigatingHandler;
+            var handler = Navigating;
             if (handler != null)
                 handler(sender, e);
 
@@ -82,18 +81,11 @@ protected virtual bool CanCloseOnNavigating(object sender, NavigatingCancelEvent
         /// <param name="e"> The event args. </param>
         protected virtual void OnNavigated(object sender, NavigationEventArgs e)
         {
-            if (e.Uri.IsAbsoluteUri || e.Content == null)
-            {
-                return;
-            }
+            if (e.Uri.IsAbsoluteUri || e.Content == null) return;
 
             ViewLocator.InitializeComponent(e.Content);
-
             var viewModel = ViewModelLocator.LocateForView(e.Content);
-            if (viewModel == null)
-            {
-                return;
-            }
+            if (viewModel == null) return;
 
             var page = e.Content as PhoneApplicationPage;
             if (page == null)
@@ -241,11 +233,7 @@ public event NavigatedEventHandler Navigated
         /// <summary>
         ///   Raised prior to navigation.
         /// </summary>
-        public event NavigatingCancelEventHandler Navigating
-        {
-            add { _externalNavigatingHandler += value; }
-            remove { _externalNavigatingHandler -= value; }
-        }
+        public event NavigatingCancelEventHandler Navigating;
 
         /// <summary>
         ///   Raised when navigation fails.

src/GlobalAssemblyInfo.cs

@@ -15,4 +15,4 @@
 #endif
 
 [assembly: AssemblyVersion("1.2.0.0")]
-[assembly: AssemblyFileVersion("1.2.2.0")]
+[assembly: AssemblyFileVersion("1.2.3.0")]