Autore Topic: mi apre una schermata bianca  (Letto 170 volte)

Offline newbie2016

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mi apre una schermata bianca
« il: 20 Luglio 2016, 12:30:04 CEST »
0
Salve, nel logcat mi da il seguente errore
Codice: [Seleziona]
E/RecyclerView: No adapter attached; skipping layout
dal menu devo aprire la schermata per la ricerca e mi visualizza una pagina bianca

il RecyckerView è il seguente

Codice (XML): [Seleziona]
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical">

    <android.support.v7.widget.RecyclerView
       android:id="@+id/utentiList"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:paddingTop="10dp"
       android:layout_weight="1"
       />
</LinearLayout>

il file Java della schermata di ricerca è il seguente:
Codice (Java): [Seleziona]
public class SearchActivity extends AppCompatActivity {

    // CONNECTION_TIMEOUT and READ_TIMEOUT are in milliseconds
    public static final int CONNECTION_TIMEOUT = 10000;
    public static final int READ_TIMEOUT = 15000;
    private RecyclerView mRVUtenti;
    private AdapterUtenti mAdapter;

    SearchView searchView = null;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_searchmain);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // adds item to action bar
        getMenuInflater().inflate(R.menu.search_main, menu);

        // Get Search item from action bar and Get Search service
        MenuItem searchItem = menu.findItem(R.id.action_search);
        SearchManager searchManager = (SearchManager) SearchActivity.this.getSystemService(Context.SEARCH_SERVICE);
        if (searchItem != null) {
            searchView = (SearchView) searchItem.getActionView();
        }
        if (searchView != null) {
            searchView.setSearchableInfo(searchManager.getSearchableInfo(SearchActivity.this.getComponentName()));
            searchView.setIconified(false);
        }

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        return super.onOptionsItemSelected(item);
    }

    // Every time when you press search button on keypad an Activity is recreated which in turn calls this function
    @Override
    protected void onNewIntent(Intent intent) {
        // Get search query and create object of class AsyncFetch
        if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
            String query = intent.getStringExtra(SearchManager.QUERY);
            if (searchView != null) {
                searchView.clearFocus();
            }
            new AsyncFetch(query).execute();

        }
    }

    // Create class AsyncFetch
    private class AsyncFetch extends AsyncTask<String, String, String> {

        ProgressDialog pdLoading = new ProgressDialog(SearchActivity.this);
        HttpURLConnection conn;
        URL url = null;
        String searchQuery;

        public AsyncFetch(String searchQuery){
            this.searchQuery=searchQuery;
        }

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

            //this method will be running on UI thread
            pdLoading.setMessage("\tLoading...");
            pdLoading.setCancelable(false);
            pdLoading.show();

        }

        @Override
        protected String doInBackground(String... params) {
            try {

                // Enter URL address where your php file resides
                url = new URL("http://www.sito.com/utenti_search.php");

            } catch (MalformedURLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                return e.toString();
            }
            try {

                // Setup HttpURLConnection class to send and receive data from php and mysql
                conn = (HttpURLConnection) url.openConnection();
                conn.setReadTimeout(READ_TIMEOUT);
                conn.setConnectTimeout(CONNECTION_TIMEOUT);
                conn.setRequestMethod("POST");

                // setDoInput and setDoOutput to true as we send and recieve data
                conn.setDoInput(true);
                conn.setDoOutput(true);

                // add parameter to our above url
                Uri.Builder builder = new Uri.Builder().appendQueryParameter("searchQuery", searchQuery);
                String query = builder.build().getEncodedQuery();

                OutputStream os = conn.getOutputStream();
                BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
                writer.write(query);
                writer.flush();
                writer.close();
                os.close();
                conn.connect();

            } catch (IOException e1) {
                // TODO Auto-generated catch block
                e1.printStackTrace();
                return e1.toString();
            }

            try {

                int response_code = conn.getResponseCode();

                // Check if successful connection made
                if (response_code == HttpURLConnection.HTTP_OK) {

                    // Read data sent from server
                    InputStream input = conn.getInputStream();
                    BufferedReader reader = new BufferedReader(new InputStreamReader(input));
                    StringBuilder result = new StringBuilder();
                    String line;

                    while ((line = reader.readLine()) != null) {
                        result.append(line);
                    }

                    // Pass data to onPostExecute method
                    return (result.toString());

                } else {
                    return("Connection error");
                }

            } catch (IOException e) {
                e.printStackTrace();
                return e.toString();
            } finally {
                conn.disconnect();
            }


        }

        @Override
        protected void onPostExecute(String result) {

            //this method will be running on UI thread
            pdLoading.dismiss();
            List<DataUtenti> data=new ArrayList<>();

            pdLoading.dismiss();
            if(result.equals("no rows")) {
                Toast.makeText(SearchActivity.this, "No Results found for entered query", Toast.LENGTH_LONG).show();
            }else{

                try {

                    JSONArray jArray = new JSONArray(result);

                    // Extract data from json and store into ArrayList as class objects
                    for (int i = 0; i < jArray.length(); i++) {
                        JSONObject json_data = jArray.getJSONObject(i);
                        DataUtenti utentiData = new DataUtenti();
                        utentiData.Cognome = json_data.getString("cognome");
                        utentiData.Nome = json_data.getString("nome");
                        utentiData.Paese = json_data.getString("paese");
                        utentiData.Zodiacale = json_data.getString("zodiacale");
                        data.add(utentiData);
                    }

                    // Setup and Handover data to recyclerview
                    mRVUtenti = (RecyclerView) findViewById(R.id.utentiList);
                    mAdapter = new AdapterUtenti(SearchActivity.this, data);
                    mRVUtenti.setAdapter(mAdapter);
                    mRVUtenti.setLayoutManager(new LinearLayoutManager(SearchActivity.this));

                } catch (JSONException e) {
                    // You to understand what actually error is and handle it appropriately
                    Toast.makeText(SearchActivity.this, e.toString(), Toast.LENGTH_LONG).show();
                    Toast.makeText(SearchActivity.this, result.toString(), Toast.LENGTH_LONG).show();
                }

            }

        }

    }
}

come posso risolverlo?

Grazie