Fehler beim Analysieren von JSON-Array in Android

Question

Ich versuche, Daten von einer Website zu extrahieren und ein Diagramm in meiner Android-Anwendung anzuzeigen. Wo mache ich einen Fehler? Es kann den JSON nicht analysieren. Ich habe einige Links durchgegangen, konnte das Problem aber nicht lösen.

Bitte schlagen Sie vor, welche Änderungen ich in den beiden Bereichen vornehmen kann.

1. Wie Werte in Blick auf [Zeile 126]
2. Ob ich Listview in der richtigen Art und Weise erklärt haben [Zeile 118] ich diese Zeilen sehen in code.Please markiert haben. Vielen Dank im Voraus

Fehler, die ich aufgeklebt

JSON Parser: Error parsing data org.json.JSONException: Expected ':' 
after n at character 5 of {n "status": "ok",n "name": "Transaction 
Rate",n "unit": "Transactions Per Second",n "period": "minute",n 
"description": "The number of Bitcoin transactions added to the 
mempool per second.",n "values": [n {n  "x": 1481383260,n  
"y": 3.060833333333333n },n {n  "x": 1481385240,n  "y": 
3.0708333333333324n },n {n  "x": 1481387220,n  "y": 

MainActivity.Java

package com.example.garima.bitcoingraph; 

import android.os.Bundle; 
import android.support.design.widget.FloatingActionButton; 
import android.support.design.widget.Snackbar; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.util.Log; 
import android.view.View; 
import android.view.Menu; 
import android.view.MenuItem; 
import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 
import org.w3c.dom.Text; 

import android.app.Activity; 
import android.app.ProgressDialog; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 
import android.widget.ListView; 
import android.widget.TextView; 

import java.util.List; 

import garima.asynctask.library.JSONParser; 

public class MainActivity extends AppCompatActivity { 
    TextView status; 
    TextView name; 
    TextView unit; 
    TextView period; 
    TextView description; 
    ListView value; 

    Button Btngetdata; 

    //URL to get JSON Array 
    private static String url = "https://api.blockchain.info/charts/transactions-per-second?timespan=5weeks&rollingAverage=8hours&format=json"; 

    //JSON Node Names 
    private static final String TAG_STATUS = "status"; 
    private static final String TAG_NAME = "name"; 
    private static final String TAG_UNIT = "unit"; 
    private static final String TAG_PERIOD = "period"; 
    private static final String TAG_DESCRIPTION="description"; 
    private static final String TAG_USER="user"; 
    private static final String TAG_VALUE="value"; 
    private static final String TAG = "MyActivity"; 
    JSONArray user = null; 

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

     setContentView(R.layout.activity_main); 
     Btngetdata = (Button)findViewById(R.id.getdata); 
     Btngetdata.setOnClickListener(new View.OnClickListener() { 

      @Override 
      public void onClick(View view) { 
       new JSONParse().execute(); 

      } 
     }); 

    } 

    private class JSONParse extends AsyncTask<String, String, JSONObject> { 
     private ProgressDialog pDialog; 
     @Override 
     protected void onPreExecute() { 
      super.onPreExecute(); 
      status = (TextView)findViewById(R.id.status); 
      name = (TextView)findViewById(R.id.name); 
      unit = (TextView)findViewById(R.id.unit); 
      period=(TextView)findViewById(R.id.period); 
      description=(TextView)findViewById(R.id.description); 
      value=(ListView)findViewById(R.id.value); 
      pDialog = new ProgressDialog(MainActivity.this); 
      pDialog.setMessage("Getting Data ..."); 
      pDialog.setIndeterminate(false); 
      pDialog.setCancelable(true); 
      pDialog.show(); 

     } 

     @Override 
     protected JSONObject doInBackground(String... args) { 
      JSONParser jParser = new JSONParser(); 

      // Getting JSON from URL 
      JSONObject json = jParser.getJSONFromUrl(url); 
      Log.i(TAG,"json found is"+json); 
      return json; 
     } 

     @Override 
     protected void onPostExecute(JSONObject json) { 
      pDialog.dismiss(); 
      Log.i(TAG,"json is"+json); 
      try { 

       // Getting JSON Array<Discuss how to get values> 
       user = json.getJSONArray(TAG_USER); 
       JSONObject c = user.getJSONObject(0); 

       // Storing JSON item in a Variable 
       String Status_Value = c.getString(TAG_STATUS); 
       String Name_Value = c.getString(TAG_NAME); 
       String Unit_Value = c.getString(TAG_UNIT); 
       String Period_Value=c.getString(TAG_PERIOD); 
       String Description_Value=c.getString(TAG_DESCRIPTION); 
       List Values_Value=c.getClass(TAG_VALUE); //118 

       //Set JSON Data in TextView 
       status.setText(Status_Value); 
       name.setText(Name_Value); 
       unit.setText(Unit_Value); 
       period.setText(Period_Value); 
       description.setText(Description_Value); 
       ->How to set values for Values?//126 

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

     } 
    } 

} 

JSON bin immer:

{ "status": "ok", 
     "name": "Transaction Rate", 
     "unit":"Transactions Per Second", 
     "period": "minute", 
     "description": "The number of Bitcoin transactions added to the mempool per second.", 
     "values": [ 
      { 
      "x": 1481385360, 
      "y": 3.069444444444444 
      }, 
      { 
      "x": 1481387340, 
      "y": 3.0919444444444437 
      }, 
      { 
      "x": 1481389320, 
      "y": 3.144861111111111 
      } 
     ] 
    } 

Hinzufügen getJSONfromURL Methode

public JSONObject getJSONFromUrl(String url) { 

     // Making HTTP request 
     try { 
      // defaultHttpClient 
      DefaultHttpClient httpClient = new DefaultHttpClient(); 
      HttpGet httpGet = new HttpGet(url); 

      HttpResponse httpResponse = httpClient.execute(httpGet); 
      HttpEntity httpEntity = httpResponse.getEntity(); 
      is = httpEntity.getContent(); 

     } catch (UnsupportedEncodingException e) { 
      e.printStackTrace(); 
     } catch (ClientProtocolException e) { 
      e.printStackTrace(); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 

     try { 
      BufferedReader reader = new BufferedReader(new InputStreamReader(
        is, "iso-8859-1"), 8); 
      StringBuilder sb = new StringBuilder(); 
      String line = null; 
      while ((line = reader.readLine()) != null) { 
       sb.append(line + "n"); 
      } 
      is.close(); 
      json = sb.toString(); 
     } catch (Exception e) { 
      Log.e("Buffer Error", "Error converting result " + e.toString()); 
     } 

     // try parse the string to a JSON object 
     try { 
      jObj = new JSONObject(json); 
     } catch (JSONException e) { 
      Log.e("JSON Parser", "Error parsing data " + e.toString()); 
     } 

     // return JSON String 
     return jObj; 

    } 
} 

Answer 1

ändern,

while ((line = reader.readLine()) != null) { 
    sb.append(line + "n"); 
} 

zu,

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

Sie gedacht haben müssen \n zu schreiben, aber die \ zu schreiben vergaß. Dies ist die Quelle der streunenden n Zeichen in Ihrem JSON.

Jetzt können Sie eine POJO-Klasse und eine GSON-Bibliothek verwenden, um die JSON zu parsen.

Answer 2

Error parsing data org.json.JSONException: Expected ':' 
> after n at character 5 of {n "status": 

Es ist ein Streuner in Ihrem json. Befreie das n.