Stack Trace custom view

System.NullReferenceException: Object reference not set to an instance of an object
  at TestCustomViewsiOS.UI.Views.SavedPhotosView+<SetSelectedFile>c__AnonStorey1.<>m__0 () [0x00012] in /Users/xxxxxxxxx/Projects/TestCustomViewsiOS/TestCustomViewsiOS/UI/Views/SavedPhotosView.cs:41
  at MonoTouch.Foundation.NSActionDispatcher.Apply () [0x00000] in /Developer/MonoTouch/Source/maccore/src/Foundation/NSAction.cs:56
  at at (wrapper managed-to-native) MonoTouch.ObjCRuntime.Messaging:void_objc_msgSend_IntPtr_IntPtr_bool (intptr,intptr,intptr,intptr,bool)
  at MonoTouch.Foundation.NSObject.InvokeOnMainThread (MonoTouch.Foundation.NSAction action) [0x00007] in /Developer/MonoTouch/Source/maccore/src/Foundation/NSObject2.cs:506
  at TestCustomViewsiOS.UI.Views.SavedPhotosView.SetSelectedFile (System.String filename, System.String filepath) [0x00027] in /Users/xxxxxxxxxx/Projects/TestCustomViewsiOS/TestCustomViewsiOS/UI/Views/SavedPhotosView.cs:40
  at TestCustomViewsiOS.ApplicationLayer.DataSource.SavedPhotosTableViewSource.RowSelected (MonoTouch.UIKit.UITableView tableView, MonoTouch.Foundation.NSIndexPath indexPath) [0x00048] in /Users/xxxxxxxxxx/Projects/TestCustomViewsiOS/TestCustomViewsiOS/Application/DataSource/SavedPhotosTableViewSource.cs:64
  at at (wrapper managed-to-native) MonoTouch.UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
  at MonoTouch.UIKit.UIApplication.Main (System.String[] args, IntPtr principal, IntPtr delegate) [0x00005] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:62
  at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:46
  at TestCustomViewsiOS.Application.Main (System.String[] args) [0x00008] in /Users/xxxxxxxxxxxx/Projects/TestCustomViewsiOS/TestCustomViewsiOS/Main.cs:17