JSON到Android的错误 [英] JSON to Android error
本文介绍了JSON到Android的错误的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我已经成功地将数据从数据库转换为json格式，我的json数据如下
I have a successfully converted data from database into json format, my json data is as follows
{"room":[{"id":"1044","location":"kathmandu","title":"room room rome",
"quantity":"2","price":"1000","contact":"9811111111","area":"1500",
"description":"kjkfs ksdjfsd kj","address":"kat"}],"success":1}
我想在android上查看这些数据，我的json解析器代码为
I want to view these data on android, my json parser code is
package com.iwantnew.www;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URLEncodedUtils;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;
import android.util.Log;
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET method
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
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;
}
}
我的查看室Java文件旨在提取json数据
my view room java file is intended to extract the json data
package com.iwantnew.www;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
//import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
public class viewroom extends ListActivity {
// url to make request
private static String url = "http://10.0.2.2/iWant/src/android_view_all_room.php";
// JSON Node names
private static final String TAG_ROOM = "room";
// private static final String TAG_SUCCESS = "success";
private static final String TAG_ID = "id";
private static final String TAG_LOCATION = "location";
private static final String TAG_TITLE = "title";
private static final String TAG_QUANTITY = "quantity";
private static final String TAG_PRICE = "price";
private static final String TAG_CONTACT = "contact";
private static final String TAG_AREA = "area";
private static final String TAG_DESCRIPTION = "description";
private static final String TAG_ADDRESS = "address";
// contacts JSONArray
JSONArray room = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.view_room);
// Hashmap for ListView
ArrayList<HashMap<String, String>> roomList = new ArrayList<HashMap<String, String>>();
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url, "GET", params);
try {
// Getting Array of Contacts
room = json.getJSONArray(TAG_ROOM);
// looping through All Contacts
for(int i = 0; i < room.length(); i++){
JSONObject c = room.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_ID);
String location = c.getString(TAG_LOCATION);
String quantity = c.getString(TAG_QUANTITY);
String address = c.getString(TAG_ADDRESS);
String price = c.getString(TAG_PRICE);
String contact = c.getString(TAG_CONTACT);
String area = c.getString(TAG_AREA);
String description = c.getString(TAG_DESCRIPTION);
String title = c.getString(TAG_TITLE);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_ID, id);
map.put(TAG_LOCATION, location);
map.put(TAG_QUANTITY, quantity);
map.put(TAG_ADDRESS, address);
map.put(TAG_PRICE, price);
map.put(TAG_CONTACT, contact);
map.put(TAG_AREA, area);
map.put(TAG_DESCRIPTION, description);
map.put(TAG_TITLE, title);
// adding HashList to ArrayList
roomList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, roomList,
R.layout.list_room,
new String[] { TAG_TITLE, TAG_LOCATION, TAG_PRICE }, new int[] {
R.id.title, R.id.location, R.id.price });
setListAdapter(adapter);
// selecting single ListView item
ListView lv = getListView();
// Launching new screen on Selecting Single ListItem
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String title = ((TextView) view.findViewById(R.id.title)).getText().toString();
String location = ((TextView) view.findViewById(R.id.location)).getText().toString();
String price = ((TextView) view.findViewById(R.id.price)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), SingleRoomActivity.class);
in.putExtra(TAG_TITLE, title);
in.putExtra(TAG_LOCATION, location);
in.putExtra(TAG_PRICE, price);
startActivity(in);
}
});
}
}
singleroom活动类旨在仅显示有关点击房间的数据， 如下
the singleroom activity class is intended to show data about clicked room only, it is as follows
package com.iwantnew.www;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class SingleRoomActivity extends Activity {
private static final String TAG_TITLE = "title";
private static final String TAG_LOCATION = "location";
private static final String TAG_PRICE = "price";
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.single_room);
// getting intent data
Intent in = getIntent();
// Get JSON values from previous intent
String title = in.getStringExtra(TAG_TITLE);
String location = in.getStringExtra(TAG_LOCATION);
String price = in.getStringExtra(TAG_PRICE);
// Displaying all values on the screen
TextView lblTitle = (TextView) findViewById(R.id.title_label);
TextView lblLocation = (TextView) findViewById(R.id.location_label);
TextView lblPrice = (TextView) findViewById(R.id.price_label);
lblTitle.setText(title);
lblLocation.setText(location);
lblPrice.setText(price);
}
}
这是我得到的日志猫错误. :(
and here is the log cat error i get. :(
推荐答案
尝试在setContentView()下的viewroom活动中使用以下代码，以避免networkOnmainThread异常.
Try using the below code inside your viewroom activity below setContentView() to avoid networkOnmainThread exception..
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
}
但是，在不阻塞主线程的情况下使用AsyncTask在后台线程内进行繁重的操作会很棒！
But, doing heavy operation inside background thread using AsyncTask without blocking main thread would be great!
这篇关于JSON到Android的错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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