解析多个JSON网址

Question

我想解析我的应用程序中的多个JSON URl，并将它们显示在一个列表视图中 但只有我能做的是显示一个URL并且我想在一个列表视图中显示多个URl，网址具有相同的数组名称和属性 这里是我的代码

@Override 
public void onStart() { 
    super.onStart(); 
    if(connectiondetector.isConnected()){ 
     new jsontask().execute(

       "https://newsapi.org/v1/articles?source=google-news&sortBy=top&apiKey=ade8f00a634b4825a028837ec107afae" 

     ); 

    }else { 
     Toast.makeText(page.this, "no internet connection",Toast.LENGTH_SHORT).show(); 

    } 


    // ATTENTION: This was auto-generated to implement the App Indexing API. 
    // See https://g.co/AppIndexing/AndroidStudio for more information. 

} 

@Override 
public void onStop() { 
    super.onStop(); 


} 



public class jsontask extends AsyncTask<String, String, List<moviemodel>> { 


    @Override 
    protected List<moviemodel> doInBackground(String... params) { 
     BufferedReader reader = null; 
     HttpURLConnection connection = null; 
     try { 
      URL url = new URL(params[0]); 
      connection = (HttpURLConnection) url.openConnection(); 
      connection.connect(); 
      InputStream stream = connection.getInputStream(); 
      reader = new BufferedReader(new InputStreamReader(stream)); 
      StringBuffer buffer = new StringBuffer(); 
      String line = ""; 
      while ((line = reader.readLine()) != null) { 
       buffer.append(line); 

      } 


      String finaljson = buffer.toString(); 
      JSONObject parentobject = new JSONObject(finaljson); 

      // JSONObject parentobject1 = parentobject.getJSONObject(""); 
      JSONArray parentarray = parentobject.getJSONArray("articles"); 
      List<moviemodel>moviemodelList = new ArrayList<>(); 
      for (int i = 0; i < parentarray.length(); i++){ 
       JSONObject finalobject = parentarray.getJSONObject(i); 
       moviemodel moviemodel = new moviemodel(); 
       moviemodel.setAuthor(finalobject.getString("author")); 
       moviemodel.setDescription(finalobject.getString("description")); 
       moviemodel.setTitle(finalobject.getString("title")); 
       moviemodel.setImage(finalobject.getString("urlToImage")); 
       moviemodel.setUrl(finalobject.getString("url")); 
       moviemodel.setPublishedAt(finalobject.getString("publishedAt")); 



       moviemodelList.add(moviemodel); 


      } 

      return moviemodelList; 

     } catch (MalformedURLException e) { 
      e.printStackTrace(); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } finally { 
      if (connection != null) { 
       connection.disconnect(); 
      } 
      try { 
       if (reader != null) { 
        reader.close(); 
       } 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 

     } 


     return null; 
    } 



    @Override 
    protected void onPostExecute(List<moviemodel> result) { 


     super.onPostExecute(result); 
     newsadapter adapter = new newsadapter(getApplicationContext(),R.layout.row, result); 
     lvnews.setAdapter(adapter); 
     lvnews.setOnScrollListener(new AbsListView.OnScrollListener() { 
      @Override 
      public void onScrollStateChanged(AbsListView view, int scrollState) { 

      } 

      @Override 
      public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { 
       if(firstVisibleItem+visibleItemCount == totalItemCount && totalItemCount!=0) 
       { 
        if(flag_loading == false) 
        { 
         flag_loading = true; 
         new jsontask().execute("https://newsapi.org/v1/articles?source=ars-technica&sortBy=top&apiKey=ade8f00a634b4825a028837ec107afae") 

         ;} 
       } 
      } 
     }); 
    } 

} 

Answer 1

你只需要声明的List<moviemodel>moviemodelList = new ArrayList<>();出的AsyncTask的和使用两个相同的列表asynctask.If使用声明里面的AsyncTask它重新列表初始化的和先前从第一个asynctask存储的数据从列表中清除。

只需声明您在create方法之上声明所有变量的列表。