public TwitterAuthPage()
        {
            InitializeComponent();

            _twitterOAuth = new TweetOAuth(AppResources.AppKey, AppResources.AppSecret, TweetAuthType.OAuth);
            TwitterWebAuth.Navigated += TwitterWebAuth_Navigated;
            //TwitterWebAuth.Navigated += _twitterOAuth.AuthWebCallBack;

        }
 public TweetAPICall()
 {
     _tweetAuthObj = new TweetOAuth();
     _tweetReturn = new ObservableCollection<Tweet>();
 }
        /// <summary>
        /// Authenticate the current user for use in Twitter
        /// </summary>
        /// <param name="AuthType"></param>
        /// <returns></returns>
        private async Task<bool> AuthenticateTwitterUser(int AuthType) 
        {
            
            bool AuthenticationStatus = false;
            TweetAuthType _selectedAuth = Convert.ToInt32(TweetAuthType.AppAuth) == AuthType ? TweetAuthType.AppAuth : TweetAuthType.OAuth;

            oauthTwitter = new TweetOAuth(_consumerKey, _consumerSecret, _selectedAuth);

            try
            {
                if (oauthTwitter.AuthenticationType == TweetAuthType.AppAuth) await oauthTwitter.AuthenticateTwitterbyAppAuth();
                else await oauthTwitter.AuthenticateTwitterByOAuth();
                //else await oauthTwitter.AuthenticateTwitterByOAuth();
                AuthenticationStatus = true;
            }
            catch (Exception ex) 
            {
                throw new Exception(ex.Message);
            }

            return AuthenticationStatus;
        }