private async void OnDownloadFile(Message message)
{
var stream = await rocketChatRest.GetFile(message.Attachments[0].ImageUrl);
var createdFile = await KnownFolders.PicturesLibrary.CreateFileAsync(message.File.Name, CreationCollisionOption.GenerateUniqueName);
var fileStream = await createdFile.OpenStreamForWriteAsync();
fileStream.Write(stream.ToArray(), 0, (int)(stream.Length));
fileStream.Close();
notificationService.ShowDownloadedFileNotification(createdFile.Name, createdFile.Path);
}
