/// <summary>
/// Populates the page with content passed during navigation. Any saved state is also
/// provided when recreating a page from a prior session.
/// </summary>
/// <param name="navigationParameter">The parameter value passed to
/// <see cref="Frame.Navigate(Type, Object)"/> when this page was initially requested.
/// </param>
/// <param name="pageState">A dictionary of state preserved by this page during an earlier
/// session. This will be null the first time a page is visited.</param>
private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
{
if (e.PageState != null)
{
QueryText = (string)e.PageState["QueryText"];
if (e.PageState.ContainsKey("Results"))
{
var results = (string)e.PageState["Results"];
QueryTask = null;
Results = JsonConvert.DeserializeObject <List <ExtendedBookItem> >(results);
LoadResultIntoView();
}
else
{
Results = null;
QueryTask = null;
}
}
else
{
QueryText = e.NavigationParameter as String;
}
if (Results == null && QueryTask == null)
{
VisualStateManager.GoToState(this, "Searching", false);
QueryTask = DmzjDocSecBase.SearchBookAsync(QueryText);
}
// TODO: Application-specific searching logic. The search process is responsible for
// creating a list of user-selectable result categories:
//
// filterList.Add(new Filter("<filter name>", <result count>));
//
// Only the first filter, typically "All", should pass true as a third argument in
// order to start in an active state. Results for the active filter are provided
// in Filter_SelectionChanged below.
var filterList = new List <Filter>();
filterList.Add(new Filter("All", 0, true));
this.DefaultViewModel["Filters"] = filterList;
// Communicate results through the view model
this.DefaultViewModel["ShowFilters"] = filterList.Count > 1;
if (QueryTask != null)
{
try
{
Results = await QueryTask;
}
catch (Exception)
{
Results = null;
}
LoadResultIntoView();
}
}
private async Task SearchForResultAsync()
{
if (QueryTask != null)
{
QueryTask.AsAsyncAction().Cancel();
}
VisualStateManager.GoToState(this, "Searching", false);
QueryTask = DmzjDocSecBase.SearchBookAsync(QueryText);
try
{
Results = await QueryTask;
}
catch (Exception)
{
Results = null;
}
QueryTask = null;
LoadResultIntoView();
}