Telerik UI for WPF => Object refrence not set to an instance of an object.

[Alen]

Hi,

I have just strated creating a Telerik WPF application, added a RadButton in a RadWindow and whenever I click on any of the buttons on the Window(minimze, maximize or RadButton) the application crashes. The debugg mode throws System.NullReferenceException: 'Object reference not set to an instance of an object.'

I have added references, of which are Telerik.Windows.Controls, Telerik.Windows.Controls.Data, Telerik.Windows.Controls.Input, Telerik.Windows.Controls.Navigation, Telerik.Windows.Data, for Telerik to the project, version: 2019.1.220.45 (of all references).

The call stack shows this output: 

>Telerik.Windows.Controls.Navigation.dll!Telerik.Windows.Controls.WindowBase.OnGotKeyboardFocus(System.Windows.Input.KeyboardFocusChangedEventArgs e)Unknown
 PresentationCore.dll!System.Windows.UIElement.OnGotKeyboardFocusThunk(object sender, System.Windows.Input.KeyboardFocusChangedEventArgs e)Unknown
 PresentationCore.dll!System.Windows.Input.KeyboardFocusChangedEventArgs.InvokeEventHandler(System.Delegate genericHandler, object genericTarget)Unknown
 PresentationCore.dll!System.Windows.RoutedEventArgs.InvokeHandler(System.Delegate handler, object target)Unknown
 PresentationCore.dll!System.Windows.RoutedEventHandlerInfo.InvokeHandler(object target, System.Windows.RoutedEventArgs routedEventArgs)Unknown
 PresentationCore.dll!System.Windows.EventRoute.InvokeHandlersImpl(object source, System.Windows.RoutedEventArgs args, bool reRaised)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseEventImpl(System.Windows.DependencyObject sender, System.Windows.RoutedEventArgs args)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseTrustedEvent(System.Windows.RoutedEventArgs args)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseEvent(System.Windows.RoutedEventArgs args, bool trusted)Unknown
 PresentationCore.dll!System.Windows.Input.InputManager.ProcessStagingArea()Unknown
 PresentationCore.dll!System.Windows.Input.InputManager.ProcessInput(System.Windows.Input.InputEventArgs input)Unknown
 PresentationCore.dll!System.Windows.Input.KeyboardDevice.ChangeFocus(System.Windows.DependencyObject focus, int timestamp)Unknown
 PresentationCore.dll!System.Windows.Input.KeyboardDevice.TryChangeFocus(System.Windows.DependencyObject newFocus, System.Windows.Input.IKeyboardInputProvider keyboardInputProvider, bool askOld, bool askNew, bool forceToNullIfFailed)Unknown
 PresentationCore.dll!System.Windows.Input.KeyboardDevice.Focus(System.Windows.DependencyObject focus, bool askOld, bool askNew, bool forceToNullIfFailed)Unknown
 PresentationCore.dll!System.Windows.Input.KeyboardDevice.Focus(System.Windows.IInputElement element)Unknown
 PresentationCore.dll!System.Windows.UIElement.Focus()Unknown
 PresentationFramework.dll!System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonDown(System.Windows.Input.MouseButtonEventArgs e)Unknown
 PresentationCore.dll!System.Windows.UIElement.OnMouseLeftButtonDownThunk(object sender, System.Windows.Input.MouseButtonEventArgs e)Unknown
 PresentationCore.dll!System.Windows.Input.MouseButtonEventArgs.InvokeEventHandler(System.Delegate genericHandler, object genericTarget)Unknown
 PresentationCore.dll!System.Windows.RoutedEventArgs.InvokeHandler(System.Delegate handler, object target)Unknown
 PresentationCore.dll!System.Windows.RoutedEventHandlerInfo.InvokeHandler(object target, System.Windows.RoutedEventArgs routedEventArgs)Unknown
 PresentationCore.dll!System.Windows.EventRoute.InvokeHandlersImpl(object source, System.Windows.RoutedEventArgs args, bool reRaised)Unknown
 PresentationCore.dll!System.Windows.UIElement.ReRaiseEventAs(System.Windows.DependencyObject sender, System.Windows.RoutedEventArgs args, System.Windows.RoutedEvent newEvent)Unknown
 PresentationCore.dll!System.Windows.UIElement.OnMouseDownThunk(object sender, System.Windows.Input.MouseButtonEventArgs e)Unknown
 PresentationCore.dll!System.Windows.Input.MouseButtonEventArgs.InvokeEventHandler(System.Delegate genericHandler, object genericTarget)Unknown
 PresentationCore.dll!System.Windows.RoutedEventArgs.InvokeHandler(System.Delegate handler, object target)Unknown
 PresentationCore.dll!System.Windows.RoutedEventHandlerInfo.InvokeHandler(object target, System.Windows.RoutedEventArgs routedEventArgs)Unknown
 PresentationCore.dll!System.Windows.EventRoute.InvokeHandlersImpl(object source, System.Windows.RoutedEventArgs args, bool reRaised)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseEventImpl(System.Windows.DependencyObject sender, System.Windows.RoutedEventArgs args)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseTrustedEvent(System.Windows.RoutedEventArgs args)Unknown
 PresentationCore.dll!System.Windows.UIElement.RaiseEvent(System.Windows.RoutedEventArgs args, bool trusted)Unknown
 PresentationCore.dll!System.Windows.Input.InputManager.ProcessStagingArea()Unknown
 PresentationCore.dll!System.Windows.Input.InputManager.ProcessInput(System.Windows.Input.InputEventArgs input)Unknown
 PresentationCore.dll!System.Windows.Input.InputProviderSite.ReportInput(System.Windows.Input.InputReport inputReport)Unknown
 PresentationCore.dll!System.Windows.Interop.HwndMouseInputProvider.ReportInput(System.IntPtr hwnd, System.Windows.Input.InputMode mode, int timestamp, System.Windows.Input.RawMouseActions actions, int x, int y, int wheel)Unknown
 PresentationCore.dll!System.Windows.Interop.HwndMouseInputProvider.FilterMessage(System.IntPtr hwnd, MS.Internal.Interop.WindowMessage msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled)Unknown
 PresentationCore.dll!System.Windows.Interop.HwndSource.InputFilterMessage(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled)Unknown
 WindowsBase.dll!MS.Win32.HwndWrapper.WndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam, ref bool handled)Unknown
 WindowsBase.dll!MS.Win32.HwndSubclass.DispatcherCallbackOperation(object o)Unknown
 WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.InternalRealCall(System.Delegate callback, object args, int numArgs)Unknown
 WindowsBase.dll!System.Windows.Threading.ExceptionWrapper.TryCatchWhen(object source, System.Delegate callback, object args, int numArgs, System.Delegate catchHandler)Unknown
 WindowsBase.dll!System.Windows.Threading.Dispatcher.LegacyInvokeImpl(System.Windows.Threading.DispatcherPriority priority, System.TimeSpan timeout, System.Delegate method, object args, int numArgs)Unknown
 WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam)Unknown
 [Native to Managed Transition]
 [Managed to Native Transition]
 WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame frame)Unknown
 WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrame(System.Windows.Threading.DispatcherFrame frame)Unknown
 PresentationFramework.dll!System.Windows.Application.RunDispatcher(object ignore)Unknown
 PresentationFramework.dll!System.Windows.Application.RunInternal(System.Windows.Window window)Unknown
 PresentationFramework.dll!System.Windows.Application.Run(System.Windows.Window window)Unknown
 PresentationFramework.dll!System.Windows.Application.Run()Unknown
 Project3.exe!Project3.App.Main()Unknown

 

I cannot find the stack trace since I don't have .pdb files(can't find them(except reporting.wpf.pdb) in the installation folder).

I'm attaching the solution.

I'm using Visual Studio 2017 Community Edition.

 

Hope you can solve the issue.

 

Sincerely,

Josip

 

[Alen]

Sorry I can't attach the .zips, can you please delete the post I will send a ticket

[Dimitar Dinev]

Hi Alen,

I explained it in your ticket and will copy the text from it, so the people in the forum with the same question can see the answer.


In order to use RadWindow as a MainWindow, you need to delete the StartupUri in App.xaml and override the OnStartup method in App.xaml.cs:

protected override void OnStartup(StartupEventArgs e)
        {
            new MainWindow().Show();
            base.OnStartup(e);
        }

You can read more in the How to use RadWindow as main Window article.

Regards,
Dimitar Dinev
Progress Telerik