private async void MicrophoneIcon_Tapped(object sender, TappedRoutedEventArgs e)
{
if (_speechService == null)
{
_speechService = new SpeechService();
}
var notifier = NotifyTaskCompletion.Create(_speechService.RecognizeAsync());
await notifier.TaskCompleted;
if (notifier.IsSuccessfullyCompleted)
{
searchBox.Text = notifier.Result;
}
}