private void SearchPerform()
        {
            if (_SearchString.Length == 0)
            {
                _ListView.Adapter  = new SearchDownAdapter(this, new List <Download>());
                _Loader.Visibility = ViewStates.Gone;
                return;
            }

            _Loader.Visibility = ViewStates.Visible;

            Thread th = new Thread(() => {
                _Downloads = DownloadManager.SearchDocuments(_SearchString);

                RunOnUiThread(() =>
                {
                    var adapter = new SearchDownAdapter(this, _Downloads);

                    adapter.OpenAction += (string p) => {
                        Intent i = new Intent();
                        i.SetClass(this, typeof(ViewerScreen));

                        i.SetAction(Intent.ActionView);

                        i.PutExtra("pubPath", p);
                        this.StartActivityForResult(i, 0);
                    };

                    _ListView.Adapter = adapter;

                    _Loader.Visibility = ViewStates.Gone;
                });
            });

            th.Start();
        }
        private void ItemClick(object sender, AdapterView.ItemClickEventArgs e)
        {
            var item = _Downloads[e.Position];

            MBDownloadManager.RequestDownload(item.Uri, new VoidNotify());

            item.Stato = DownloadStato.Downloading;

            //_ListView.Adapter = new SearchDownAdapter(this, _Downloads);

            var adapter = new SearchDownAdapter(this, _Downloads);

            adapter.OpenAction += (string p) => {
                Intent i = new Intent();
                i.SetClass(this, typeof(ViewerScreen));

                i.SetAction(Intent.ActionView);

                i.PutExtra("pubPath", p);
                this.StartActivityForResult(i, 0);
            };

            _ListView.Adapter = adapter;
        }