/// <summary>
/// Invoked when a filter is selected using the ComboBox in snapped view state.
/// </summary>
/// <param name="sender">The ComboBox instance.</param>
/// <param name="e">Event data describing how the selected filter was changed.</param>
void Filter_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
// Determine what filter was selected
var selectedFilter = e.AddedItems.FirstOrDefault() as Filter;
if (selectedFilter != null)
{
// Mirror the results into the corresponding Filter object to allow the
// RadioButton representation used when not snapped to reflect the change
selectedFilter.Active = true;
// TODO: Respond to the change in active filter by setting this.DefaultViewModel["Results"]
// to a collection of items with bindable Image, Title, Subtitle, and Description properties
var videos = App.DataSource.TopicGroups.SelectMany(g =>
g.Playlists.SelectMany(p => p.Videos.Where(v =>
Regex.IsMatch(v.Name ?? "", _queryText, RegexOptions.IgnoreCase) ||
Regex.IsMatch(v.Description ?? "", _queryText, RegexOptions.IgnoreCase))))
.Distinct(VideoItem.CreateComparer());
this.DefaultViewModel["Results"] = videos.ToArray();
// Ensure results are found
object results;
ICollection resultsCollection;
if (this.DefaultViewModel.TryGetValue("Results", out results) &&
(resultsCollection = results as ICollection) != null &&
resultsCollection.Count != 0)
{
VisualStateManager.GoToState(this, "ResultsFound", true);
return;
}
}
// Display informational text when there are no search results.
VisualStateManager.GoToState(this, "NoResultsFound", true);
}
public async void LaunchApp(ApplicationExecutionState previousExecutionState)
{
DataSource = new KhanDataSource();
await DataSource.LoadAllData();
SearchPane searchPane = SearchPane.GetForCurrentView();
searchPane.PlaceholderText = "Search Khan Academy";
searchPane.QuerySubmitted +=
(sender, queryArgs) =>
{
KhanAcademy.SearchResultsPage.Activate(queryArgs.QueryText, previousExecutionState);
};
searchPane.SuggestionsRequested +=
(sender, suggestionArgs) =>
{
var videos = App.DataSource.TopicGroups.SelectMany(g =>
g.Playlists.SelectMany(p => p.Videos.Where(v =>
Regex.IsMatch(v.Name ?? "", suggestionArgs.QueryText, RegexOptions.IgnoreCase) ||
Regex.IsMatch(v.Description ?? "", suggestionArgs.QueryText, RegexOptions.IgnoreCase))))
.Distinct(VideoItem.CreateComparer())
.Take(3);
foreach (VideoItem vi in videos)
{
suggestionArgs.Request.SearchSuggestionCollection.AppendQuerySuggestion(vi.Title);
}
var recommended = App.DataSource.TopicGroups.SelectMany(g =>
g.Playlists.SelectMany(p => p.Videos.Where(v =>
Regex.IsMatch(v.Name ?? "", suggestionArgs.QueryText, RegexOptions.IgnoreCase)))).FirstOrDefault();
if (recommended != null)
{
suggestionArgs.Request.SearchSuggestionCollection.AppendSearchSeparator("Recommended");
IRandomAccessStreamReference imgStream = RandomAccessStreamReference.CreateFromUri(recommended.ImagePath);
suggestionArgs.Request.SearchSuggestionCollection.AppendResultSuggestion(recommended.Title, recommended.Description, recommended.VideoPath.ToString(), imgStream, recommended.Title);
}
};
searchPane.ResultSuggestionChosen +=
(sender, resultArgs) =>
{
var recommended = App.DataSource.TopicGroups.SelectMany(g =>
g.Playlists.SelectMany(p => p.Videos.Where(v =>
Regex.IsMatch(v.VideoPath.ToString() ?? "", resultArgs.Tag, RegexOptions.IgnoreCase)))).FirstOrDefault();
Frame f = Window.Current.Content as Frame;
f.Navigate(typeof(VideoPage), JsonSerializer.Serialize(recommended));
};
if (previousExecutionState == ApplicationExecutionState.Running)
{
Window.Current.Activate();
return;
}
var rootFrame = new Frame();
SuspensionManager.RegisterFrame(rootFrame, "AppFrame");
if (previousExecutionState == ApplicationExecutionState.Terminated)
{
await SuspensionManager.RestoreAsync();
}
if (rootFrame.Content == null)
{
// When the navigation stack isn't restored navigate to the first page,
// configuring the new page by passing required information as a navigation
// parameter
if (!rootFrame.Navigate(typeof(HubPage), JsonSerializer.Serialize(DataSource.TopicGroups)))
{
throw new Exception("Failed to create initial page");
}
}
// Place the frame in the current Window and ensure that it is active
Window.Current.Content = rootFrame;
Window.Current.Activate();
}