protected override async void OnInitialize()
{
base.OnInitialize();
// If page have been launched by search panel we query database. Results are automaticly updated (see MainViewModel constructor) so we have to be aware that
// manufacturers will not be used in 'QueryForDatasheets' as they aren't loaded yet.
Query = Parameter ?? "";
await Task.Factory.StartNew(() =>
{
Manufacturers.AddRange(DatasheetDataSource.GetManufacturers());
// Get ungrouped manufacters
_ungroupedManufacters = (from manusGroupedByLetter in Manufacturers from manu in manusGroupedByLetter select manu).ToList <Manufacturer>();
});
// Load manufacturers logos
await DatasheetDataSource.LoadManufacturersImagesAsync();
}
private async void FindMoreResults()
{
// Prevent any double task
_previousTokenSource?.Cancel(true);
//TODO : wait the canceled task.
_currentTokenSource = new CancellationTokenSource();
_previousTokenSource = _currentTokenSource;
try
{
_currentTokenSource.Token.ThrowIfCancellationRequested();
IsProcesssing = true;
var data = await Task.Factory.StartNew(() =>
{
if (ManufacturerSelectionEnabled)
{
return(DatasheetDataSource.SearchForDatasheet(Query, _currentTokenSource.Token, _selectedManufacturers));
}
return(DatasheetDataSource.SearchForDatasheet(Query, _currentTokenSource.Token));
}, _currentTokenSource.Token);
_currentTokenSource.Token.ThrowIfCancellationRequested();
_datasheets.Clear();
Datasheets.UnionWith(data);
NotifyOfPropertyChange(nameof(Datasheets));
NotifyOfPropertyChange(nameof(DatasheetsCount));
ViewDatasheets = new Common.IncrementalLoadingDatasheetList(Datasheets.ToList(), _ungroupedManufacters);
IsMoreResult = false;
_currentTokenSource.Token.ThrowIfCancellationRequested();
await ViewDatasheets.LoadMoreItemsAsync(120);
_currentTokenSource.Token.ThrowIfCancellationRequested();
IsProcesssing = false;
}
catch (OperationCanceledException) { }
}
// TODO : quand on recherche avec tout les résultats, conserver seulement les manufacturers concernés
/// <summary>
/// Searches matching part datasheet in SQLite database.
/// The criteria used to query the database are the selected manufacturers and the user query (from 'selectedManufacturers' and 'Query').
/// </summary>
private async void QueryForDatasheets()
{
// Cancel old datasheet queries and create a new CancellationTokenSource
if (_previousTokenSource != null)
{
_previousTokenSource.Cancel(true);
}
// TODO : wait for the canceled task (task cancelling is not instantaneous !)
_currentTokenSource = new CancellationTokenSource();
_previousTokenSource = _currentTokenSource;
IsZeroManufacturerSelected = false;
IsEmptyResult = false;
// TODO : règler le problème d'affichage de "0 datasheet trouvées" pendant la recherche ! (cf TODO dans le XAML)
IsMoreResult = false;
try
{
if (IsAnyQuery)
{
_currentTokenSource.Token.ThrowIfCancellationRequested();
IsProcesssing = true;
if (_datasheets.Count != 0)
{
_datasheets.Clear();
NotifyOfPropertyChange <HashSet <Part> >(() => Datasheets);
NotifyOfPropertyChange <int>(() => DatasheetsCount);
}
IList <Part> data = await Task.Factory.StartNew(() =>
{
if (ManufacturerSelectionEnabled)
{
return(DatasheetDataSource.SearchForDatasheet(Query, _currentTokenSource.Token, _selectedManufacturers, FIRST_SEARCH_RANGE));
}
return(DatasheetDataSource.SearchForDatasheet(Query, _currentTokenSource.Token, FIRST_SEARCH_RANGE));
}, _currentTokenSource.Token);
_currentTokenSource.Token.ThrowIfCancellationRequested();
Datasheets.UnionWith(data);
NotifyOfPropertyChange(nameof(Datasheets));
NotifyOfPropertyChange(nameof(DatasheetsCount));
// Preparation de l'incremental loading et affichage de la première page.
ViewDatasheets = new Common.IncrementalLoadingDatasheetList(Datasheets.ToList(), _ungroupedManufacters);
IsMoreResult = Datasheets.Count == FIRST_SEARCH_RANGE;
_currentTokenSource.Token.ThrowIfCancellationRequested();
await ViewDatasheets.LoadMoreItemsAsync(FIRST_SEARCH_RANGE);
_currentTokenSource.Token.ThrowIfCancellationRequested();
IsProcesssing = false;
}
_currentTokenSource.Token.ThrowIfCancellationRequested();
if (Datasheets.Count == 0)
{
if (ManufacturerSelectionEnabled && _selectedManufacturers.Count == 0)
{
IsZeroManufacturerSelected = true;
}
else
{
IsEmptyResult = true;
}
}
else
{
IsZeroManufacturerSelected = false;
IsEmptyResult = false;
}
}
catch (OperationCanceledException) { }
}
