Dynamo.Controls.DynamoView.DynamoView_KeyDown C# (CSharp) Method

        private void DynamoView_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.Key != Key.Escape || !IsMouseOver) return;

            var vm = dynamoViewModel.BackgroundPreviewViewModel;


            // ESC key to navigate has long lag on some machines.
            // This issue was caused by using KeyEventArgs.IsRepeated API
            // In order to fix this we need to use our own extension method DelayInvoke to determine
            // whether ESC key is being held down or not
            if (!IsEscKeyPressed && !vm.NavigationKeyIsDown)
            {
                IsEscKeyPressed = true;
                dynamoViewModel.UIDispatcher.DelayInvoke(navigationInterval, () =>
                {
                    if (IsEscKeyPressed)
                    {
                        vm.NavigationKeyIsDown = true;
                    }
                });
            }           

            else
            {
                vm.CancelNavigationState();
            }

            e.Handled = true;
        }