WP8.1 app crashes when navigating to another page

Question

It's a data-bound windows phone 8.1 (universal) app. When I navigate to a detailed view of the item from the main page it works like a charm. When I use the same code to navigate from another page to the same detailed one, my app closes and I get no exception. Code is the same as in the hub default sample when you open a new hub project. This is the code I use to navigate to he page.

 private void ItemView_ItemClick(object sender, ItemClickEventArgs e)
    {
        {
            // Navigate to the appropriate destination page, configuring the new page
            // by passing required information as a navigation parameter
            var itemId = ((SampleDataItem)e.ClickedItem).UniqueId;

            if (!Frame.Navigate(typeof(Session), itemId))
            {
                throw new Exception(this.resourceLoader.GetString("NavigationFailedExceptionMessage"));
            }
        }
    }

and this is the code I use to handle the loading

private async void NavigationHelper_LoadState(object sender, LoadStateEventArgs e)
    {

        // TODO: Create an appropriate data model for your problem domain to replace the sample data
        var item = await SampleDataSource.GetItemAsync((string)e.NavigationParameter);
        this.DefaultViewModel["Item"] = item;


    }

The code stops after hitting the last bracket and the app exits. Until then it works as it should, the values are correct and it finds the specific item!

Answer 1

Found the solution here and changed my code to

 private async void ItemView_ItemClick(object sender, ItemClickEventArgs e)
    {
        {

            var itemId = ((SampleDataItem)e.ClickedItem).UniqueId;

            await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => Frame.Navigate(typeof(Session), itemId));


        }
    }

I still don't understand this error, but it is now solved.