protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            SetContentView(Resource.Layout.dropboxAuthorization);

            // For adding webview js must be enabled and add INTERNET permission to AndroidManifest xml
            _web = this.FindViewById<WebView>(Resource.Id.webViewBox);
            _web.Settings.JavaScriptEnabled = true;
            _web.Settings.JavaScriptCanOpenWindowsAutomatically = true;
            _web.Settings.SetSupportZoom(false);
            _web.SetScrollContainer(true);
            _web.SetNetworkAvailable(true);

            _webClient = new DropboxAuthizationWebviewClient();
            _webClient._authorization = this;

            _web.ClearCache(true);
            _web.ClearHistory();
            _web.ClearFormData();
            clearCacheFolder(this.CacheDir);
            this.DeleteDatabase("webview.db");
            this.DeleteDatabase("webviewCache.db");

            var _url = DropboxHelper.GetInstance().GetAuthorizationURL();
            if (_url.Contains("connect_login"))
            {
                _url = _url.Replace("connect_login", "logout");
            }
            else
            {
                _url = "https://www.dropbox.com/logout?cont=" + System.Web.HttpUtility.UrlEncode(_url); //_url.Replace(":", "%3A").Replace("?","%3D");
            }

            _web.LoadUrl(_url);

            _web.SetWebViewClient(_webClient);

            var button = this.FindViewById<Button>(Resource.Id.testbutton);
            button.Click += button_Click;
        }