Recyclerview + JSON + Fragment + Android

Question

Я пытаюсь передать Arraylist с объектами, полученными из JSON, и перейти к другому фрагменту в Android Studio.

Вот класс, который я хочу, чтобы получить массив

@Override 
    public View onCreateView(LayoutInflater inflater, 
          ViewGroup container, 
          Bundle savedInstanceState) { 
     View view = inflater.inflate(R.layout.fragment_car, container, false); 

     new AsyncTaskParseJson().execute(); 



     mRecyclerView = (RecyclerView) view.findViewById(R.id.rv_list); 
     mRecyclerView.setHasFixedSize(true); 
     mRecyclerView.addOnItemTouchListener(new RecyclerViewTouchListener(getActivity(), mRecyclerView, this)); 

     LinearLayoutManager llm = new LinearLayoutManager(getActivity()); 
     llm.setOrientation(LinearLayoutManager.VERTICAL); 
     mRecyclerView.setLayoutManager(llm); 

     CarAdapter adapter = new CarAdapter(getActivity(), mList); 
     mRecyclerView.setAdapter(adapter); 

     return view; 
    } 

Это мой класс, который создает массив:

public class AsyncTaskParseJson extends AsyncTask<String, String, String> { 

     final String TAG = "AsyncTaskParseJson.java"; 
     String yourJsonStringUrl = "http://marciowelben.servidorturbo.net/getjson.php"; 
     JSONArray dataJsonArr = null; 

     @Override 
     protected void onPreExecute() {} 

     @Override 
     protected String doInBackground(String... arg0) { 

      try { 
       JsonParser jParser = new JsonParser(); 
       JSONObject json = jParser.getJSONFromUrl(yourJsonStringUrl); 
       dataJsonArr = json.getJSONArray("emp_info"); 
       for (int i = 0; i < dataJsonArr.length(); i++) { 

        JSONObject c = dataJsonArr.getJSONObject(i); 

        // Storing each json item in variable 
        String firstname = c.getString("employee name"); 
        String lastname = c.getString("employee no"); 

        Car d = new Car(firstname, lastname, R.mipmap.ic_launcher); 
        listAux.add(d); 
       } 

      } catch (JSONException e) { 
       e.printStackTrace(); 
      } 
      mList = listAux; 
      return null; 
     } 
    } 

Так я просто хочу, чтобы заполнить мой Recyclerview с этим массивом ,

Answer 1

Поскольку вы добавляете адаптер сначала, прежде чем ждать возвращения данных, вам нужно будет позвонить notifyDataSetChanged(), чтобы адаптер перерисовал список после того, как он будет обработан. Другой способ выполнения этого - ожидание возврата результата, а затем установка адаптера. См. Ниже

public class MainActivity extends AppCompatActivity { 
private static final String TAG = "RecyclerViewExample"; 

    private List<FeedItem> feedItemList = new ArrayList<FeedItem>(); 

    private RecyclerView mRecyclerView; 

    private MyRecyclerAdapter adapter; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     setContentView(R.layout.activity_main); 

     /* Initialize recyclerview */ 
     mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view); 
     mRecyclerView.setLayoutManager(new LinearLayoutManager(this)); 

     /*Downloading data from below url*/ 
     final String url = "http://javatechig.com/api/get_category_posts/?dev=1&slug=android"; 
     new AsyncHttpTask().execute(url); 
    } 

    public class AsyncHttpTask extends AsyncTask<String, Void, Integer> { 

     @Override 
     protected void onPreExecute() { 
      setProgressBarIndeterminateVisibility(true); 
     } 

     @Override 
     protected Integer doInBackground(String... params) { 
      InputStream inputStream = null; 
      Integer result = 0; 
      HttpURLConnection urlConnection = null; 

      try { 
       /* forming th java.net.URL object */ 
       URL url = new URL(params[0]); 

       urlConnection = (HttpURLConnection) url.openConnection(); 

       /* for Get request */ 
       urlConnection.setRequestMethod("GET"); 

       int statusCode = urlConnection.getResponseCode(); 

       /* 200 represents HTTP OK */ 
       if (statusCode == 200) { 

        BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream())); 
        StringBuilder response = new StringBuilder(); 
        String line; 
        while ((line = r.readLine()) != null) { 
         response.append(line); 
        } 

        parseResult(response.toString()); 
        result = 1; // Successful 
       }else{ 
        result = 0; //"Failed to fetch data!"; 
       } 

      } catch (Exception e) { 
       Log.d(TAG, e.getLocalizedMessage()); 
      } 

      return result; //"Failed to fetch data!"; 
     } 

     @Override 
     protected void onPostExecute(Integer result) { 

      setProgressBarIndeterminateVisibility(false); 

      /* Download complete. Lets update UI */ 
      if (result == 1) { 
       adapter = new MyRecyclerAdapter(MainActivity.this, feedItemList); 
       mRecyclerView.setAdapter(adapter); 
      } else { 
       Log.e(TAG, "Failed to fetch data!"); 
      } 
     } 
    } 

    private void parseResult(String result) { 
     try { 
      JSONObject response = new JSONObject(result); 
      JSONArray posts = response.optJSONArray("posts"); 

      /*Initialize array if null*/ 
      if (null == feedItemList) { 
       feedItemList = new ArrayList<FeedItem>(); 
      } 

      for (int i = 0; i < posts.length(); i++) { 
       JSONObject post = posts.optJSONObject(i); 

       FeedItem item = new FeedItem(); 
       item.setTitle(post.optString("title")); 
       item.setThumbnail(post.optString("thumbnail")); 
       feedItemList.add(item); 
      } 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 
    } 

} 

Answer 2

1.Design Recycleview in layout 
    <android.support.v7.widget.RecyclerView 
     android:id="@+id/recycler_view" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:paddingTop="10dp" 
     android:layout_weight="1" 
     /> 
2.add dependency in gradle.build 
compile 'com.android.support:recyclerview-v7:23.1.1' 

3.Write the code in Activity 

public class DoctorInformationActivity extends AppCompatActivity { 

    String URL="YOUR URL"; 

    JSONArray Cities=null; 

    ArrayList<DocotorInformation> doctorList =new ArrayList<DocotorInformation>(); 
    Sqlitedatabase sql; 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.doctor_information_listview); 
     sql=new Sqlitedatabase(getApplicationContext()); 
     ConnectivityManager connectivityManager 
       = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); 
     NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo(); 
     if(activeNetworkInfo != null && activeNetworkInfo.isConnected()) 
     { 
      Toast.makeText(getApplicationContext()," connect",Toast.LENGTH_LONG).show(); 
      new JSONAsyncTask().execute(); 
     } 
     else 
     { 
      ArrayList<DocotorInformation> listdata=sql.getAllContacts(); 
      doctorList=listdata; 
      RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view); 


      DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList); 
      recyclerView.setAdapter(mAdapter); 
      recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext())); 

      Toast.makeText(getApplicationContext(),"Not connect",Toast.LENGTH_LONG).show(); 
     } 


    } 

    private class JSONAsyncTask extends AsyncTask<String, Void, JSONArray> { 

     private ProgressDialog dialog = new ProgressDialog(DoctorInformationActivity.this); 

     @Override 
     protected void onPreExecute() { 
      this.dialog.setMessage("Please wait"); 
      this.dialog.show(); 
     } 

     @Override 
     protected JSONArray doInBackground(String... urls) { 
      try { 

       //------------------>> 
       HttpGet httppost = new HttpGet(URL); 
       HttpClient httpclient = new DefaultHttpClient(); 
       HttpResponse response = httpclient.execute(httppost); 

       // StatusLine stat = response.getStatusLine(); 
       int status = response.getStatusLine().getStatusCode(); 

       if (status == 200) { 
        HttpEntity entity = response.getEntity(); 
        String data = EntityUtils.toString(entity); 


        JSONObject jsono = new JSONObject(data); 
        Cities = jsono.getJSONArray("SearchDoctorsData"); 
        return Cities; 
       } 


      } catch (IOException e) { 
       e.printStackTrace(); 
      } catch (JSONException e) { 

       e.printStackTrace(); 
      } 
      return Cities; 
     } 

     protected void onPostExecute(JSONArray result) { 
      dialog.dismiss(); 
      System.out.println(result); 

      for (int i = 0; i < result.length(); i++) { 
       JSONObject c = null; 
       try { 
        DocotorInformation doc=new DocotorInformation(); 
        c = result.getJSONObject(i); 
        doc.setName(c.getString("DoctorName")); 
        doc.setNumber(c.getString("Mobile")); 
        doctorList.add(doc); 

        sql.insertData(doc); 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 

      } 

      RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view); 


     DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList); 
     recyclerView.setAdapter(mAdapter); 
     recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext())); 


    } 
} 
} 


public class DoctorAdapter extends RecyclerView.Adapter<DoctorAdapter.ViewHolder> { 
private ArrayList<DocotorInformation> countries; 
Context con; 
public DoctorAdapter(Context c ,ArrayList<DocotorInformation> countries) { 
    this.con=c; 
     this.countries = countries; 
     } 

@Override 
public DoctorAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) { 
     View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.doctor_textviews, viewGroup, false); 
     return new ViewHolder(view); 
     } 

@Override 
public void onBindViewHolder(DoctorAdapter.ViewHolder viewHolder, int i) { 
    viewHolder.name.setText(countries.get(i).getName()); 
     viewHolder.number.setText(countries.get(i).getNumber()); 
     } 

@Override 
public int getItemCount() { 
     return countries.size(); 
     } 

public class ViewHolder extends RecyclerView.ViewHolder{ 
    private TextView name,number; 
    public ViewHolder(View view) { 
     super(view); 

     name = (TextView)view.findViewById(R.id.name); 
     number = (TextView)view.findViewById(R.id.numebr); 
    } 
} 

}