NullReferenceException: オブジェクト参照がオブジェクト インスタンスに設定されていません。
StackTrace:
   場所 Quicker.App.<>c__DisplayClass28_0.AiGn4KboGjl()
   場所 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   場所 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   場所 System.Windows.Threading.DispatcherOperation.InvokeImpl()
   場所 MS.Internal.CulturePreservingExecutionContext.CallbackWrapper(Object obj)
   場所 System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   場所 System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   場所 System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   場所 MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
   場所 System.Windows.Threading.DispatcherOperation.Invoke()
   場所 System.Windows.Threading.Dispatcher.ProcessQueue()
   場所 System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   場所 MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   場所 MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   場所 System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   場所 System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
   場所 System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   場所 MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   場所 MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   場所 System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)