1 files changed, 31 insertions, 0 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 47450a68e..f06bd88de 100644
--- a/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
+++ b/Software/Visual_Studio/PPC/Tango.PPC.UI/Navigation/DefaultNavigationManager.cs
@@ -34,6 +34,14 @@ namespace Tango.PPC.UI.Navigation
 
         private Stack<String> _navigationHistory;
 
+        /// <summary>
+        /// Gets the current view model.
+        /// </summary>
+        public PPCViewModel CurrentVM
+        {
+            get { return _currentVM as PPCViewModel; }
+        }
+
         private IPPCModule _currentModule;
         /// <summary>
         /// Gets or sets the current module.
@@ -339,5 +347,28 @@ namespace Tango.PPC.UI.Navigation
                 return false;
             }
         }
+
+        /// <summary>
+        /// Clears the navigation back history.
+        /// </summary>
+        public void ClearHistory()
+        {
+            _navigationHistory.Clear();
+            RaisePropertyChanged(nameof(CanNavigateBack));
+        }
+
+        public void ClearHistoryExcept<T>()
+        {
+            var history_list = _navigationHistory.ToList();
+            history_list = history_list.Where(x => x.Contains(typeof(T).Name)).Distinct().ToList();
+            _navigationHistory.Clear();
+
+            foreach (var item in history_list)
+            {
+                _navigationHistory.Push(item);
+            }
+
+            RaisePropertyChanged(nameof(CanNavigateBack));
+        }
     }
 }