从资产获取JSON数组数据

Question

这是我的应用程序，当我输入17603号火车时，输入编辑文本并输入按钮。 我将纠正它，从资产文件夹中获取traindetails.txt，并将其转换为字符串，然后将该字符串传递给json数组。 它将显示在logcat中。 在这里我没有任何错误。

JSON Requset存储在Assets文件夹中的.txt位置

{  
    "status":"OK",
    "result":{  
       "trainno":"17603",
       "route":[  
          {  
             "code":"KCG",
             "name":"Kacheguda",
             "arr":"First",
             "dep":"21:00",
             "day":1,
             "stop":"Y",
             "dts":"2.5"
          }
       ]
    }
}

主要活动

    package com.example.trainroutes;
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import org.json.JSONArray;
    import org.json.JSONException;
    import org.json.JSONObject;

    import android.support.v7.app.ActionBarActivity;
    import android.os.Bundle;
    import android.util.Log;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.ListView;
    import android.widget.Toast;

    public class MainActivity extends ActionBarActivity implements OnClickListener {
        private EditText train_search_editText;
        private Button submit_button;
        private ListView train_listview;

        // private String jsonStirng ;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            train_search_editText = (EditText) findViewById(R.id.trainSearch);
            submit_button = (Button) findViewById(R.id.search_train_button);
            train_listview = (ListView) findViewById(R.id.trian_name_listview);
            submit_button.setOnClickListener(this);


        }

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            if (train_search_editText.getText().toString().equals("17603")) {
                try {
                    // Reading text file from the assets folder
                    StringBuffer stringBuffer = new StringBuffer();
                    BufferedReader bufferReader = null;
                    try {
                        bufferReader = new BufferedReader(new InputStreamReader(
                                getAssets().open("traindetails.txt")));
                        String temp;
                        while ((temp = bufferReader.readLine()) != null) {
                            stringBuffer.append(temp);
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    } finally {
                        try {
                            bufferReader.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    String jsonStirng = stringBuffer.toString();
                    Log.e("Json String", "JSON String"+jsonStirng);
                    // creating jsonobject from string

                    JSONObject jsonMainObj = new JSONObject(jsonStirng);
                    // creating json array from json object

                    JSONArray jsonArrayObject = jsonMainObj.getJSONArray("route");
                    for (int i = 0; i < jsonArrayObject.length(); i++) {
                        JSONObject jsonObject = jsonArrayObject.getJSONObject(i);
                        // getting data from individual object
                        String code = jsonObject.getString("code");
                        String name = jsonObject.getString("name");
                        String arr = jsonObject.getString("arr");
                        String dep = jsonObject.getString("dep");
                        int day = jsonObject.getInt("day");
                        String stop = jsonObject.getString("stop");
                        String dts = jsonObject.getString("dts");

                        Log.d("JSONObject", "train " + name.toString());
                    }

                } catch (JSONException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            } else {
                Toast.makeText(getApplicationContext(), "Invalid  ",
                        Toast.LENGTH_SHORT).show();
            }
        }
    }

Answer 1

这是你应该怎么做

 String jsonString = loadJSONFromAsset(getApplicationContext());

    try {
        JSONObject jsonMainObj = new JSONObject(jsonString);


        JSONObject jsonArrayObjectResult = jsonMainObj.getJSONObject("result");
        JSONArray jsonArrayObjectRoute = jsonArrayObjectResult.getJSONArray("route");
        for (int i = 0; i < jsonArrayObjectRoute.length(); i++) {
            JSONObject jsonObject = jsonArrayObjectRoute.getJSONObject(i);
            // getting data from individual object
            String code = jsonObject.getString("code");
            String name = jsonObject.getString("name");
            String arr = jsonObject.getString("arr");
            String dep = jsonObject.getString("dep");
            int day = jsonObject.getInt("day");
            String stop = jsonObject.getString("stop");
            String dts = jsonObject.getString("dts");

            Log.d("JSONObject", "train " + name.toString());
        }


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

 public String loadJSONFromAsset(Context mContext) {
    String json = null;
    try {

        InputStream is = mContext.getAssets().open("test.json");
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        json = new String(buffer, "UTF-8");
    } catch (Exception e) {
        e.printStackTrace();
    }
    return json;

}

Answer 2

使用此代码

package com.example.trainroutes;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity implements OnClickListener {
    private EditText train_search_editText;
    private Button submit_button;
    private ListView train_listview;

    // private String jsonStirng ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        train_search_editText = (EditText) findViewById(R.id.trainSearch);
        submit_button = (Button) findViewById(R.id.search_train_button);
        train_listview = (ListView) findViewById(R.id.trian_name_listview);
        submit_button.setOnClickListener(this);


    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        if (train_search_editText.getText().toString().equals("17603")) {
            try {
                // Reading text file from the assets folder
                StringBuffer stringBuffer = new StringBuffer();
                BufferedReader bufferReader = null;
                try {
                    bufferReader = new BufferedReader(new InputStreamReader(
                            getAssets().open("traindetails.txt")));
                    String temp;
                    while ((temp = bufferReader.readLine()) != null) {
                        stringBuffer.append(temp);
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                } finally {
                    try {
                        bufferReader.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                String jsonStirng = stringBuffer.toString();
                Log.e("Json String", "JSON String"+jsonStirng);
                // creating jsonobject from string

                JSONObject jsonMainObj = new JSONObject(jsonStirng);

 JSONObject jsonresultObject=jsonMainObj.getJsonObject("result")
                // creating json array from json object

                JSONArray jsonArrayObject = jsonresultObject.getJSONArray("route");
                for (int i = 0; i < jsonArrayObject.length(); i++) {
                    JSONObject jsonObject = jsonArrayObject.getJSONObject(i);
                    // getting data from individual object
                    String code = jsonObject.getString("code");
                    String name = jsonObject.getString("name");
                    String arr = jsonObject.getString("arr");
                    String dep = jsonObject.getString("dep");
                    int day = jsonObject.getInt("day");
                    String stop = jsonObject.getString("stop");
                    String dts = jsonObject.getString("dts");

                    Log.d("JSONObject", "train " + name.toString());
                }

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        } else {
            Toast.makeText(getApplicationContext(), "Invalid  ",
                    Toast.LENGTH_SHORT).show();
        }
    }
}