When appointment is extended/shrink for the first time after loading app, i get null ref exception, if i drag and drop it first and then try to expand

[Colin]

Hi,

I have created a database for the RadScheduleView following Telerik
tutorials. I am able to create the database, save appointments with their
categories, time markers etc.

When I load the app, I have few appointments displayed
correctly, I can double click to edit them, I can drag them around, and expand
or shrink them. However there is one problem, if I load the app and the first
thing I do is try to expand or shrink an appointment I get this:

 

System.NullReferenceException was unhandled
  HResult=-2147467261
  Message=Object
reference not set to an instance of an object.
Source=Telerik.Windows.Controls.ScheduleView
  StackTrace:
       at
Telerik.Windows.Controls.ScheduleViewBase.<>c__DisplayClass23.<GetDecorationBlocksForSlot>b__1f(IGroupItemInfo
info)
       at
System.Linq.Enumerable.WhereListIterator`1.MoveNext()
       at
System.Linq.Enumerable.<SelectManyIterator>d__14`2.MoveNext()
       at
System.Linq.Enumerable.<SelectManyIterator>d__14`2.MoveNext()
       at
Telerik.Windows.Controls.CollectionExtensions.ForEach[T](IEnumerable`1 source,
Action`1 action)
       at
Telerik.Windows.Controls.HighlightPanel.MeasureOverride(Size availableSize)
       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.RenderMessageHandler(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.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.DispatcherOperation.InvokeImpl()
       at
System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
       at
System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at
System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       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.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
       at
System.Windows.Threading.Dispatcher.Invoke(DispatcherPriority priority, Delegate method, Object arg)
       at
MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
       at
MS.Win32.UnsafeNativeMethods.DoDragDrop(IDataObject dataObject, IOleDropSource dropSource, Int32 allowedEffects, Int32[] finalEffect)
       at
System.Windows.OleServicesContext.OleDoDragDrop(IDataObject dataObject,IOleDropSource dropSource, Int32 allowedEffects, Int32[] finalEffect)
       at
System.Windows.DragDrop.OleDoDragDrop(DependencyObject dragSource, DataObjectdataObject, DragDropEffects allowedEffects)
       at System.Windows.DragDrop.DoDragDrop(DependencyObject dragSource, Object data, DragDropEffects allowedEffects)
       at
Telerik.Windows.DragDrop.DragDropManager.DoDragDrop(DependencyObject dragSource, Object data, DragDropEffects allowedEffects, DragDropKeyStates
initialKeyState, Object dragVisual, Point relativeStartPoint, Point dragVisualOffset)
       at
Telerik.Windows.DragDrop.DragInitializer.StartDrag()
       at
Telerik.Windows.DragDrop.DragInitializer.StartDragPrivate(UIElement sender)
       at Telerik.Windows.DragDrop.DragInitializer.DragSourceOnMouseMove(Object
sender, MouseEventArgs e)
       at
System.Windows.Input.MouseEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
       at
System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
       at
System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs
       at
System.Windows.RouteItem.InvokeHandler(RoutedEventArgs routedEventArgs)
       at
System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
       at
System.Windows.EventRoute.InvokeHandlers(Object source, RoutedEventArgs args)
       at
System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs
args)
       at
System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
       at
System.Windows.UIElement.RaiseEvent(RoutedEventArgs args, Boolean trusted)
       at
System.Windows.Input.InputManager.ProcessStagingArea()
       at
System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
       at
System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
       at
System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y,
Int32 wheel)
       at
System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at
System.Windows.Interop.HwndSource.InputFilterMessage(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.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.Dispatcher.WrappedInvoke(Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
       at
System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
       at
System.Windows.Threading.Dispatcher.Invoke(DispatcherPriority priority, Delegate method, Object arg)
       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.TranslateAndDispatchMessage(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
ScheduleViewTest.App.Main() in c:\Apps\TelerikDatabase\TelerikScheduleViewDatabase\ScheduleViewTest\obj\x86\Debug\App.g.cs:line
0
       at System.AppDomain._nExecuteAssembly(RuntimeAssemblyassembly, String[] args)
       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.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at
System.Threading.ExecutionContext.Run(ExecutionContext executionContext,ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at
System.Threading.ExecutionContext.Run(ExecutionContext executionContext,ContextCallback callback, Object state)
       at
System.Threading.ThreadHelper.ThreadStart()
  InnerException:

This only happens if I try to extend or shrink First, if I drag
and drop and then try to extend or shrink then its working properly, what
settings are need to make it work properly?

Kind Regards

[Colin]

Hi,

Are there any news on the above question? Ive added the logic for the recurrence now, and exactly the same happens, I can not expand or shrink any of the appointment, unless i first drag it on the screen.

Kind Regards

[Yana]

Hello Colin,

I have tested our Binding to Database example for WPF uploaded here, but I did not manage to reproduce the reported issue. Could you give us more details on your approach, what is different in your project than the one I referenced? Any additional information you could provide will be of great help.

I am looking forward to your reply.

Regards,
Yana
Telerik

 

 

[Colin]

Hi Yana,

Actually there is not much difference, I am using Entity Framework 6.1 code first, and I think that the only thing.
Please have a look at the Example app, and tell me what needs to be changed. This contains 4 projects,

-         CreateDatabase, is just a console app which
drops and creates a database, only when I want to quickly clear the data for
testing, or I made change to the model and want them to be applied (without
migrations because im just testing at the moment)

-         TelerikScheduleViewDatabase (contains the POCOs and the helper classes)

-        ScheduleViewTest – is a wpf app which I build to test the ScheduleView behaviour with the above POCOs and database (code behind).

-         TestApp – is the wpf part that I took from the project you provided in the link, it is to test to see if your project would work (mvvm).

If you run any of the wpf apps, and add some appointments save them (the first one saves when you add an appointment and click ok, the second one has a save button on the scheduleView), close the app and run it again, then try to expand that appointment you created you will get a null reference axception, however if you drag and drop it first and then try to expand that’s absolutely fine and it will work. The only exception from that is in Timeline view I can expand the appointment straight after loading the app.

Please have a look at the Example app, and tell me what needs to be changed.

Kind Regards

[Yana]

Hi Colin,

I am pasting the reply from the support ticket regarding the same issue:

The reason for the reported exception is that initially the appointments do not have their TimeZone property set. In your SqlAppointment.cs class (inside TelerikScheduleViewDatabase project), you should implement the TimeZone property like this:

private TimeZoneInfo timeZone;

public TimeZoneInfo TimeZone
{
    get
    {
        if (this.timeZone == null)
        {
            return TimeZoneInfo.Local;
        }
        return this.timeZone;
    }
    set
    {
        if (this.timeZone != value)
        {
            this.timeZone = value;
            this.OnPropertyChanged("TimeZone");
        }
    }
 }

This should fix the error.

Regards,
Yana
Telerik