Question

我正在尝试从网址获取json数据。我的数据如下所示：

[{"Food1":"Fried Chicken","Food2":"Spagetti","Food3":"Watermelon"}]

我搜索过它，几乎尝试了我能找到的每个代码。但他们不适合我。当我手动提供json数据时我可以轻松解析它，真正的问题是通过使用HttpClient或Httpurlconnection从url获取数据。我也尝试使用AsyncTask，但是我猜想我做不到。我该怎么办？

Logcat：https://dl.dropboxusercontent.com/u/108584907/logcat.txt

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

public class yemekhane extends Activity {

public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.yemekhane);

    TextView tv = (TextView) findViewById(R.id.TextView01);


    JSONArray jArray = null;
    String result = "";
    StringBuilder sb = null;
    InputStream is = null;

    ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();

    try{
         HttpClient httpclient = new DefaultHttpClient();

         //Why to use 10.0.2.2
         HttpPost httppost = new HttpPost("http://example.com");
         httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
         HttpResponse response = httpclient.execute(httppost);
         HttpEntity entity = response.getEntity();
         is = entity.getContent();
         }catch(Exception e){
             Log.e("log_tag", "Error in http connection"+e.toString());
        }


    //convert response to string
    try{
          BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
           sb = new StringBuilder();
           sb.append(reader.readLine() + "\n");

           String line="0";
           while ((line = reader.readLine()) != null) {
                          sb.append(line + "\n");
            }
            is.close();
            result=sb.toString();


            }catch(Exception e){
                  Log.e("log_tag", "Error converting result "+e.toString());
            }


    String name = "";

          try {
            jArray = new JSONArray(result);
              JSONObject json_data=null;
              for(int i=0;i<jArray.length();i++){
                     json_data = jArray.getJSONObject(i);
                     name=json_data.getString("Food1");
              }  
        } catch (JSONException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
          tv.setText("test " + name);


    }


}`

Answer 1

感谢您的建议，我终于找到了答案。首先，我在Android Manifest xml文件中将minsdkversion更改为9。然后我在下面添加了这段代码：

StrictMode.ThreadPolicy policy = new StrictMode.
ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);

它对我有用，希望它对其他人也有效：）

无法从android中的url获取json数据

1 个答案: