public MainPage()
{
InitializeComponent();
CheckPermission();
CrossTextToSpeech.Current.Speak(WelcomeEntry.Text);
VoiceRecorder = DependencyService.Get <IVoiceRecorder>();
SpeechService = new SpeechService(new AuthenticationService(Constants.BingSpeechApiKey));
}
protected async override void OnAppearing()
{
await SpeechService.InitAuth();
base.OnAppearing();
}