protected virtual void OnLoadingError()
{
if (LoadingError != null)
{
LoadingError.Invoke(this, System.EventArgs.Empty);
}
}
protected virtual void OnLoadingError(Exception e)
{
ResetState();
_synchronizationContext.Send(state =>
{
LoadingError?.Invoke(this, new ErrorEventArgs(e));
}, 0);
}
public override void OnLoadingError(ILevelInfo pLevel, string error)
{
LoadingError?.Invoke(new EventArgs <ILevelInfo, string>(pLevel, error));
}
private async Task LoadFolderAsync(string id = null)
{
// Cancel any previous operation
_cancellationTokenSource?.Cancel();
_cancellationTokenSource = new CancellationTokenSource();
// Check if session is set
if (AuthenticationService == null)
{
throw new InvalidOperationException($"No {nameof(AuthenticationService)} has been specified");
}
// Keep a local copy of the token because the source can change while executing this function
var token = _cancellationTokenSource.Token;
// Add an option to the REST API in order to get thumbnails for each file
// https://docs.microsoft.com/en-us/onedrive/developer/rest-api/api/driveitem_list_thumbnails
var options = new[]
{
new QueryOption("$expand", "thumbnails"),
};
// Create the graph request builder for the drive
IDriveRequestBuilder driveRequest = AuthenticationService.GraphClient.Me.Drive;
// If folder id is null, the request refers to the root folder
IDriveItemRequestBuilder driveItemsRequest;
if (id == null)
{
driveItemsRequest = driveRequest.Root;
}
else
{
driveItemsRequest = driveRequest.Items[id];
}
// Raise the loading event
FolderLoading?.Invoke(this, EventArgs.Empty);
try
{
try
{
// Make a API request loading 50 items per time
var page = await driveItemsRequest.Children.Request(options).Top(50).GetAsync(token);
token.ThrowIfCancellationRequested();
// Load each page
await LoadGridItemsAsync(page, token);
token.ThrowIfCancellationRequested();
}
finally
{
// Raise the loaded event
FolderLoaded?.Invoke(this, EventArgs.Empty);
}
}
catch (OperationCanceledException)
{ }
catch (Exception ex)
{
// Raise the error event
LoadingError?.Invoke(this, ex);
}
}
