private async void Query_ContentsChanged(IStorageQueryResultBase sender, object args)
{
// Run on UI thread.
await App.Current.NavigationService.Frame.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, async() =>
{
var tracker = _folder.TryGetChangeTracker();
if (tracker != null)
{
var changeReader = tracker.GetChangeReader();
var changes = await changeReader.ReadBatchAsync();
foreach (var change in changes)
{
if (change.ChangeType == StorageLibraryChangeType.ChangeTrackingLost)
{
// Change tracker is in an invalid state and must be reset
// This should be a very rare case, but must be handled
tracker.Reset();
return;
}
if (change.IsOfType(StorageItemTypes.File))
{
// Process file change on UI thread.
await ProcessFileChange(change);
}
else if (change.IsOfType(StorageItemTypes.Folder))
{
// No-op; not interested in folders
}
else
{
if (change.ChangeType == StorageLibraryChangeType.Deleted)
{
// TODO: The application does not have to support FAT drives at the moment. NTFS is enough.
//UnknownItemRemoved(change.Path);
}
}
}
// If any changes were recorded, save database.
if (changes.Count > 0)
{
// Log query contens changed saving.
GalleryLog.QueryContentsChangedSaving();
await DatabaseUtils.SaveAllMetadatasAsync(MediaDatas);
}
await changeReader.AcceptChangesAsync();
}
});
}