private void SearchSuggestionSourceChangedHandler(ISearchSuggestionsSource newSearchSuggestionSource)
{
if (m_searchSuggestionsController != null)
{
m_searchSuggestionsController.SearchSuggestionsSource = newSearchSuggestionSource;
}
}
/// <summary>
/// Starts a new task for the search and propagates the result via the <see cref="SearchSuggestionsChanged" /> event.
/// This method does some technical stuff and delegates the actual search to the <see cref="ISearchSuggestionsSource" />.
/// </summary>
/// <param name="searchTerm">The term to search for</param>
public void Search(string searchTerm)
{
string id = Guid.NewGuid().ToString();
ISearchSuggestionsSource searchSuggestionsSource = null;
lock (m_lockObject)
{
searchSuggestionsSource = m_searchSuggestionsSource;
// no source, no search
if (searchSuggestionsSource == null)
{
return;
}
LastId = id;
}
Task.Delay(SearchDelay)
.ContinueWith((prevTask) =>
{
// search only if there was no other request during the delay
if (DoSearchWithId(id))
{
IList <string> searchSuggestions = null;
bool isFromHistory = false;
if (!string.IsNullOrEmpty(searchTerm))
{
searchSuggestions = searchSuggestionsSource.GetAutoCompletion(searchTerm);
isFromHistory = false;
}
else
{
searchSuggestions = searchSuggestionsSource.GetSearchSuggestions();
isFromHistory = true;
}
// a final check if this result will not be replaced by another active search
if (DoSearchWithId(id))
{
SearchSuggestionsChanged?.Invoke(this, new SearchSuggestionsChangedEventArgs(searchSuggestions, isFromHistory));
}
}
});
}
/// <summary>
/// Creates a new <see cref="SearchSuggestionsController" />.
/// </summary>
public SearchSuggestionsController()
{
m_searchSuggestionsSource = null;
m_lastId = null;
}
