Error on drag

[nuno]

I am geting a null ref exception when draging appointments

{"Object reference not set to an instance of an object."}
  
at Telerik.Windows.Controls.ScheduleViewBase.HaveSameElements[T](IEnumerable`1 c1, IEnumerable`1 c2) in c:\Builds\WPF_Scrum\Release_WPF_2010_Q3\Sources\Development\Controls\ScheduleView\ScheduleView\Controls\ScheduleView.DragDrop.cs:line 228
   at Telerik.Windows.Controls.ScheduleView.Slot.Equals(Object obj) in c:\Builds\WPF_Scrum\Release_WPF_2010_Q3\Sources\Development\Controls\ScheduleView\ScheduleView\Selection\Slot.cs:line 80
   at Telerik.Windows.Controls.ScheduleViewBase.HaveSameElements[T](IEnumerable`1 c1, IEnumerable`1 c2) in c:\Builds\WPF_Scrum\Release_WPF_2010_Q3\Sources\Development\Controls\ScheduleView\ScheduleView\Controls\ScheduleView.DragDrop.cs:line 228
   at Telerik.Windows.Controls.HighlightPanel.MeasureOverride(Size availableSize) in c:\Builds\WPF_Scrum\Release_WPF_2010_Q3\Sources\Development\Controls\ScheduleView\ScheduleView\Selection\HighlightDecorationsPanel.cs:line 82
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.ContextLayoutManager.UpdateLayout()
   at System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg)
   at System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork()
   at System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
   at System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
   at System.Windows.Media.MediaContext.AnimatedRenderMessageHandler(Object resizedCompositionTarget)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
   at System.Threading.ExecutionContext.runTryCode(Object userData)
   at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
   at System.Windows.Threading.Dispatcher.Run()
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at System.Windows.Application.Run(Window window)
   at System.Windows.Application.Run()
   at Escalasv01.App.Main() in C:\Work\BT\Escalasv0.1\Escalasv0.1\obj\x86\Debug\App.g.cs:line 0
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

[George]

Hi Nuno,

Could you please give us more details about this exception? When did it happen?  If you send us a sample running project that reproduces the problem it would be very helpful in further pinpointing the problem.

I am glad to assist you further.
 

Kind regards,
George
the Telerik team

[nuno]

Its hapening when using entity framework 4 ctp 5 wth alot o apointments
just a simple drag.
To were I can send the mail with the code!?

[nuno]

Its hapening when using entity framework 4 ctp 5 with alot apointments
just a simple drag cause the exception.
To were I can send the mail with the code!?

[George]

Hi Nuno,

You could send a support ticket with the attached project.  We will be glad to assist you further.


All the best,
George
the Telerik team

[nuno]

The problem is solved after change the data access with rest services. I think the problem was entity framework proxies or lazy loading.