System.NullReferenceException: Object reference not set to an instance of an object.

[mohanadasari]

Getting this exception while using spinner control. had downloaded the source code and fixed issue locally, how do we put the fix as part of upcoming release. Fix details,
Filename: LottieSharp-master\LottieSharp\WpfSurface\D2dControl.cs
on line number 135 inside method "OnIsFrontBufferAvailableChanged" added null check as follows if (d3DSurface != null && d3DSurface.IsFrontBufferAvailable)

Exception Details: Unhandled exception
System.NullReferenceException: Object reference not set to an instance of an object.
at LottieSharp.WpfSurface.D2dControl.OnIsFrontBufferAvailableChanged(Object sender, DependencyPropertyChangedEventArgs e)
at System.Windows.DependencyPropertyChangedEventHandler.Invoke(Object sender, DependencyPropertyChangedEventArgs e)
at System.Windows.Interop.D3DImage.IsFrontBufferAvailablePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
at System.Windows.Freezable.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
at System.Windows.DependencyObject.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
at System.Windows.DependencyObject.SetValue(DependencyPropertyKey key, Object value)
at System.Windows.Interop.D3DImage.SetIsFrontBufferAvailable(Object isAvailableVersionPair)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
at System.Windows.Threading.DispatcherOperation.InvokeImpl()
at MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
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 MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext 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 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, 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 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.Application.RunDispatcher(Object ignore)
at System.Windows.Application.RunInternal(Window window)
at Sncr.Cloud.UI.App.Main()
An unhandled exception of type 'System.NullReferenceException' occurred in WindowsBase.dll
Object reference not set to an instance of an object.

[mohanadasari]

@OmidID It will be great if we we come to know about expected release for the issue.

[hristowwe]

I got same problem

[saklanmazozgur]

I have the same problem, did you find a solution?

[hristowwe]

I have the same problem, did you find a solution?

No you can use MediaElement or this lib https://github.com/XamlAnimatedGif/WpfAnimatedGif

[jm-parent]

Hey !

Had the same issue.

1 - Put your json in solution

2 - Check settings

3 - Check your .csproj and find the new line

4 - Update your xaml

Thats how i fix mine :)

Hope it will help you too

[saklanmazozgur]

You're great, it worked for me, thank you.