A lot of work !!!

1 files changed, 107 insertions, 83 deletions

diff --git a/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs b/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
index 8914d55a5..4c36c3cbe 100644
--- a/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
+++ b/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
@@ -24,8 +24,16 @@ namespace Tango.PPC.UI.Navigation
     /// <seealso cref="Tango.PPC.Common.Navigation.INavigationManager" />
     public class DefaultNavigationManager : ExtendedObject, INavigationManager
     {
-        private event Action<Object, Object> NavigationCycleCompleted;
+        //private event Action<Object, Object> NavigationCycleCompleted;
+        //private event Action<Object, Object> BeforeNavigationCycleCompleted;
+        private class AwaitingVMResult
+        {
+            public PPCViewModel FromVM { get; set; }
+            public PPCViewModel ToVM { get; set; }
+            public Action Action { get; set; }
+        }
 
+        private List<AwaitingVMResult> _awaitingVMResults;
         private IDispatcherProvider _dispatcherProvider;
         private IPPCModuleLoader _moduleLoader;
         private Object _currentVM;
@@ -69,6 +77,8 @@ namespace Tango.PPC.UI.Navigation
         /// <param name="moduleLoader">The module loader.</param>
         public DefaultNavigationManager(IPPCModuleLoader moduleLoader, IDispatcherProvider dispatcherProvider)
         {
+            IsBackEnabled = true;
+            _awaitingVMResults = new List<AwaitingVMResult>();
             _navigationHistory = new Stack<String>();
             _moduleLoader = moduleLoader;
 
@@ -118,21 +128,12 @@ namespace Tango.PPC.UI.Navigation
                 FrameworkElement toView = null;
 
                 toView = MainView.Instance.NavigationControl.NavigateTo(view.ToString(), () =>
-                 {
-                     var fromVM = toView.DataContext as PPCViewModel;
-
-                     if (fromVM != null)
-                     {
-                         fromVM.OnNavigatedFrom();
-                     }
+                {
+                    NotifyOnNavigated(fromView.DataContext, toView.DataContext);
 
-                     var toVM = toView.DataContext as PPCViewModel;
+                });
 
-                     if (toVM != null)
-                     {
-                         toVM.OnNavigatedTo();
-                     }
-                 });
+                NotifyOnBeforeNavigated(fromView.DataContext, toView.DataContext);
 
                 return Task.FromResult(true);
             }
@@ -193,7 +194,7 @@ namespace Tango.PPC.UI.Navigation
         /// Navigates to the specified module and view by full path (e.g Jobs.JobsView).
         /// </summary>
         /// <param name="fullPath">The full path.</param>
-        public async Task<bool> NavigateTo(String fullPath, bool pushToHistory = true)
+        public async Task<bool> NavigateTo(String fullPath, bool pushToHistory = true, Action<PPCViewModel, PPCViewModel> onNavigating = null, Action<PPCViewModel, PPCViewModel> onNavigated = null)
         {
             String[] path = fullPath.Split('.');
             var module = _moduleLoader.UserModules.SingleOrDefault(x => x.GetType().Name == path[0] || x.Name == path[0]);
@@ -247,6 +248,13 @@ namespace Tango.PPC.UI.Navigation
                 {
                     moduleNavigation.RegisterForLoadedOrNow(async (x, e) =>
                     {
+                        var lastView = moduleNavigation.GetElement(path.Last());
+
+                        if (lastView != null)
+                        {
+                            onNavigating?.Invoke(fromVM as PPCViewModel, lastView.DataContext as PPCViewModel);
+                        }
+
                         foreach (var view in path.Skip(1))
                         {
                             await Task.Delay(100);
@@ -257,16 +265,14 @@ namespace Tango.PPC.UI.Navigation
                             {
                                 if (v != null)
                                 {
-                                    var toVM = v.DataContext as PPCViewModel;
-
-                                    if (toVM != null)
-                                    {
-                                        (fromVM as PPCViewModel)?.OnNavigatedFrom();
-                                        (toVM as PPCViewModel)?.OnNavigatedTo();
-                                    }
+                                    NotifyOnNavigated(fromVM, v.DataContext);
+                                    onNavigated?.Invoke(fromVM as PPCViewModel, v.DataContext as PPCViewModel);
+                                    NotifyAwaitingVMResults(fromVM as PPCViewModel, v.DataContext as PPCViewModel);
                                 }
                             });
 
+                            NotifyOnBeforeNavigated(fromVM, v.DataContext);
+
                             if (v != null)
                             {
                                 _currentVM = v.DataContext;
@@ -281,40 +287,34 @@ namespace Tango.PPC.UI.Navigation
                                 throw LogManager.Log(new ArgumentNullException("Could not navigate to " + fullPath));
                             }
                         }
-
-                        NavigationCycleCompleted?.Invoke(fromVM, _currentVM);
                     });
                 }
                 else
                 {
-                    await Task.Delay(navigationControl.TransitionDuration.TimeSpan);
+                    onNavigating?.Invoke(fromVM as PPCViewModel, _currentVM as PPCViewModel);
 
-                    if (fromVM is PPCViewModel)
-                    {
-                        (fromVM as PPCViewModel)?.OnNavigatedFrom();
-                    }
+                    NotifyOnBeforeNavigated(fromVM, _currentVM);
 
-                    if (_currentVM is PPCViewModel)
-                    {
-                        (_currentVM as PPCViewModel)?.OnNavigatedTo();
-                    }
+                    await Task.Delay(navigationControl.TransitionDuration.TimeSpan);
 
-                    NavigationCycleCompleted?.Invoke(fromVM, _currentVM);
+                    NotifyOnNavigated(fromVM, _currentVM);
+
+                    onNavigated?.Invoke(fromVM as PPCViewModel, _currentVM as PPCViewModel);
+                    NotifyAwaitingVMResults(fromVM as PPCViewModel, _currentVM as PPCViewModel);
                 }
             }
             else
             {
+                NotifyOnBeforeNavigated(fromVM, _currentVM);
+
+                onNavigating?.Invoke(fromVM as PPCViewModel, _currentVM as PPCViewModel);
+
                 await Task.Delay(navigationControl.TransitionDuration.TimeSpan);
 
-                if (fromVM is PPCViewModel)
-                {
-                    (fromVM as PPCViewModel)?.OnNavigatedFrom();
-                }
+                NotifyOnNavigated(fromVM, _currentVM);
 
-                if (_currentVM is PPCViewModel)
-                {
-                    (_currentVM as PPCViewModel)?.OnNavigatedTo();
-                }
+                onNavigated?.Invoke(fromVM as PPCViewModel, _currentVM as PPCViewModel);
+                NotifyAwaitingVMResults(fromVM as PPCViewModel, _currentVM as PPCViewModel);
             }
 
             return true;
@@ -330,46 +330,35 @@ namespace Tango.PPC.UI.Navigation
         /// <param name="obj">The object.</param>
         /// <param name="pushToHistory">if set to <c>true</c> [push to history].</param>
         /// <returns></returns>
-        public Task<TResult> NavigateForResult<TModule, TView, TResult, TObject>(TObject obj, bool pushToHistory = true)
+        public async Task<TResult> NavigateForResult<TModule, TView, TResult, TObject>(TObject obj, bool pushToHistory = true)
                where TModule : IPPCModule
         {
             TaskCompletionSource<TResult> source = new TaskCompletionSource<TResult>();
 
             var fromVM = _currentVM;
-            Object toVM = null;
-
 
-            Action<Object, Object> handler = null;
-
-            handler = (from, to) =>
+            await NavigateTo(typeof(TModule).Name + "." + typeof(TView).Name, pushToHistory, (from, to) =>
             {
-                if (toVM == null)
-                {
-                    toVM = to;
-                    if (toVM is INavigationResultProvider<TResult, TObject>)
-                    {
-                        (toVM as INavigationResultProvider<TResult, TObject>).OnNavigationObjectReceived(obj);
-                    }
-                }
-                else
+                _awaitingVMResults.Add(new AwaitingVMResult()
                 {
-                    if (to == fromVM && from == toVM)
+                    FromVM = fromVM as PPCViewModel,
+                    ToVM = to as PPCViewModel,
+                    Action = () =>
                     {
-                        if (from is INavigationResultProvider<TResult, TObject>)
+                        if (to is INavigationResultProvider<TResult, TObject>)
                         {
-                            source.SetResult((from as INavigationResultProvider<TResult, TObject>).GetNavigationResult());
+                            source.SetResult((to as INavigationResultProvider<TResult, TObject>).GetNavigationResult());
                         }
                     }
+                });
 
-                    NavigationCycleCompleted -= handler;
+                if (to is INavigationResultProvider<TResult, TObject>)
+                {
+                    (to as INavigationResultProvider<TResult, TObject>).OnNavigationObjectReceived(obj);
                 }
-            };
-
-            NavigationCycleCompleted += handler;
+            });
 
-            NavigateTo<TModule>(typeof(TView).Name, pushToHistory);
-
-            return source.Task;
+            return await source.Task;
         }
 
         /// <summary>
@@ -383,25 +372,13 @@ namespace Tango.PPC.UI.Navigation
         /// <returns></returns>
         public Task<bool> NavigateWithObject<TModule, TView, TPass>(TPass obj, bool pushToHistory = true) where TModule : IPPCModule
         {
-            TaskCompletionSource<bool> source = new TaskCompletionSource<bool>();
-
-            Action<Object, Object> handler = null;
-
-            handler = (from, to) =>
+            return NavigateTo(typeof(TModule).Name + "." + typeof(TView).Name, pushToHistory, (fromVM, toVM) =>
             {
-                if (to is INavigationObjectReceiver<TPass>)
+                if (toVM is INavigationObjectReceiver<TPass>)
                 {
-                    (to as INavigationObjectReceiver<TPass>).OnNavigatedToWithObject(obj);
+                    (toVM as INavigationObjectReceiver<TPass>).OnNavigatedToWithObject(obj);
                 }
-
-                NavigationCycleCompleted -= handler;
-            };
-
-            NavigationCycleCompleted += handler;
-
-            NavigateTo<TModule>(typeof(TView).Name, pushToHistory);
-
-            return source.Task;
+            });
         }
 
         private Task<bool> NavigateTo(Type moduleType, bool pushToHistory = true, params String[] viewPath)
@@ -424,6 +401,16 @@ namespace Tango.PPC.UI.Navigation
             get { return _navigationHistory.Count > 0; }
         }
 
+        private bool _isBackEnabled;
+        /// <summary>
+        /// Gets a value indicating whether the back should be enabled.
+        /// </summary>
+        public bool IsBackEnabled
+        {
+            get { return _isBackEnabled; }
+            set { _isBackEnabled = value; RaisePropertyChangedAuto(); }
+        }
+
         /// <summary>
         /// Navigates to the previous view if <see cref="P:Tango.PPC.Common.Navigation.INavigationManager.CanNavigateBack" /> is true.
         /// </summary>
@@ -493,5 +480,42 @@ namespace Tango.PPC.UI.Navigation
 
             RaisePropertyChanged(nameof(CanNavigateBack));
         }
+
+        private void NotifyOnBeforeNavigated(object fromVM, object toVM)
+        {
+            if (fromVM is PPCViewModel)
+            {
+                (fromVM as PPCViewModel)?.OnBeforeNavigatedFrom();
+            }
+
+            if (toVM is PPCViewModel)
+            {
+                (toVM as PPCViewModel)?.OnBeforeNavigatedTo();
+            }
+        }
+
+        private void NotifyOnNavigated(object fromVM, object toVM)
+        {
+            if (fromVM is PPCViewModel)
+            {
+                (fromVM as PPCViewModel)?.OnNavigatedFrom();
+            }
+
+            if (toVM is PPCViewModel)
+            {
+                (toVM as PPCViewModel)?.OnNavigatedTo();
+                (toVM as PPCViewModel)?.OnNavigatedTo(fromVM as PPCViewModel);
+            }
+        }
+
+        private void NotifyAwaitingVMResults(PPCViewModel fromVM, PPCViewModel toVM)
+        {
+            var awaiter = _awaitingVMResults.SingleOrDefault(x => x.FromVM == toVM && x.ToVM == fromVM);
+            if (awaiter != null)
+            {
+                _awaitingVMResults.Remove(awaiter);
+                awaiter.Action();
+            }
+        }
     }
 }