internal async Task <bool> TryLogInWithUserInputCredentialAsync() { if (IsSignedIn) { return(true); } if (String.IsNullOrWhiteSpace(UserName) || String.IsNullOrWhiteSpace(Password)) { return(false); } try { IsSignedIn = await AppGlobal.SignInAsync(UserName, Password) != null; } catch (Exception) { IsSignedIn = false; AppGlobal.User = null; } if (IsSignedIn) { UserName = AppGlobal.User.UserName; } return(IsSignedIn); }