Java 如何使用JSON对象解析URL-Android
我有一个包含JSON对象的URL（.com）。。我使用PHP创建了JSON对象，并将其上传到服务器中，以便动态更新（类似于RSS）。我面临两个问题，第一个显示错误“并且java.Lang.String类型无法转换为JSON对象”，因此我使用了以下代码，错误如下：Java 如何使用JSON对象解析URL-Android,java,android,Java,Android,我有一个包含JSON对象的URL（.com）。。我使用PHP创建了JSON对象，并将其上传到服务器中，以便动态更新（类似于RSS）。我面临两个问题，第一个显示错误“并且java.Lang.String类型无法转换为JSON对象”，因此我使用了以下代码，错误如下： public class JSONParser { static InputStream is = null; static JSONObject jObj = null; static String json = ""; // c
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject getJSONFromUrl(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
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;
}
}
public class SingleMenuItemActivity extends Activity {
// JSON node keys
private static final String TAG_Title = "Title";
private static final String TAG_Date = "Date";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.single_list_item);
// getting intent data
Intent in = getIntent();
// Get JSON values from previous intent
String name = in.getStringExtra(TAG_Title);
String description = in.getStringExtra(TAG_Date);
// Displaying all values on the screen
TextView lblName = (TextView) findViewById(R.id.name_label);
TextView lblCost = (TextView) findViewById(R.id.email_label);
lblName.setText(name);
lblCost.setText(description);
}
}
public class AndroidJSONParsingActivity extends ListActivity {
// url to make request
private static String url = "http://www.rssparser.host22.com/";
// JSON Node names
private static final String TAG_NAME = "Title";
private static final String TAG_Image = "Image";
private static final String TAG_Category = "Category";
private static final String TAG_Venue = "Venue";
private static final String TAG_Date = "Date";
// contacts JSONArray
JSONArray contacts = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Hashmap for ListView
ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONObject json = jParser.getJSONFromUrl(url);
try {
// Getting Array of Contacts
//contacts = json.getJSONArray(TAG_CONTACTS);
// looping through All Contacts
for(int i = 0; i < contacts.length(); i++){
JSONObject c = contacts.getJSONObject(i);
// Storing each json item in variable
String name = c.getString(TAG_NAME);
String Image = c.getString(TAG_Image);
String Category = c.getString(TAG_Category);
String Venue = c.getString(TAG_Venue);
String Date = c.getString(TAG_Date);
// Phone number is agin JSON Object
JSONObject phone = c.getJSONObject(TAG_Date);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_NAME, name);
map.put(TAG_Image, Image);
map.put(TAG_Date , Date );
// adding HashList to ArrayList
contactList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, contactList,
R.layout.list_item,
new String[] { TAG_NAME, TAG_Date }, new int[] {
R.id.name, R.id.email, R.id.mobile });
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 name = ((TextView) view.findViewById(R.id.name)).getText().toString();
String cost = ((TextView) view.findViewById(R.id.email)).getText().toString();
String description = ((TextView) view.findViewById(R.id.mobile)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
in.putExtra(TAG_NAME, name);
in.putExtra(TAG_Date, description);
startActivity(in);
}
});
}
}
public class SingleMenuItemActivity extends Activity {
// JSON node keys
private static final String TAG_Title = "Title";
private static final String TAG_Date = "Date";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.single_list_item);
// getting intent data
Intent in = getIntent();
// Get JSON values from previous intent
String name = in.getStringExtra(TAG_Title);
String description = in.getStringExtra(TAG_Date);
// Displaying all values on the screen
TextView lblName = (TextView) findViewById(R.id.name_label);
TextView lblCost = (TextView) findViewById(R.id.email_label);
lblName.setText(name);
lblCost.setText(description);
}
}
public class AndroidJSONParsingActivity extends ListActivity {
// url to make request
private static String url = "http://www.rssparser.host22.com/";
// JSON Node names
private static final String TAG_NAME = "Title";
private static final String TAG_Image = "Image";
private static final String TAG_Category = "Category";
private static final String TAG_Venue = "Venue";
private static final String TAG_Date = "Date";
// contacts JSONArray
JSONArray contacts = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Hashmap for ListView
ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONObject json = jParser.getJSONFromUrl(url);
try {
// Getting Array of Contacts
//contacts = json.getJSONArray(TAG_CONTACTS);
// looping through All Contacts
for(int i = 0; i < contacts.length(); i++){
JSONObject c = contacts.getJSONObject(i);
// Storing each json item in variable
String name = c.getString(TAG_NAME);
String Image = c.getString(TAG_Image);
String Category = c.getString(TAG_Category);
String Venue = c.getString(TAG_Venue);
String Date = c.getString(TAG_Date);
// Phone number is agin JSON Object
JSONObject phone = c.getJSONObject(TAG_Date);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_NAME, name);
map.put(TAG_Image, Image);
map.put(TAG_Date , Date );
// adding HashList to ArrayList
contactList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, contactList,
R.layout.list_item,
new String[] { TAG_NAME, TAG_Date }, new int[] {
R.id.name, R.id.email, R.id.mobile });
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 name = ((TextView) view.findViewById(R.id.name)).getText().toString();
String cost = ((TextView) view.findViewById(R.id.email)).getText().toString();
String description = ((TextView) view.findViewById(R.id.mobile)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
in.putExtra(TAG_NAME, name);
in.putExtra(TAG_Date, description);
startActivity(in);
}
});
}
}
公共类AndroidJSONParsingActivity扩展了ListActivity{
//发出请求的url
专用静态字符串url=”http://www.rssparser.host22.com/";
//JSON节点名称
私有静态最终字符串标记\u NAME=“Title”；
私有静态最终字符串TAG_Image=“Image”；
私有静态最终字符串标记_Category=“Category”；
专用静态最终字符串标记_vention=“vention”；
私有静态最终字符串标记_Date=“Date”；
//联系JSONArray
JSONArray联系人=null；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
//ListView的Hashmap
ArrayList contactList=新建ArrayList（）；
//创建JSON解析器实例
JSONParser jParser=新的JSONParser（）；
//从URL获取JSON字符串
JSONObject json=jParser.getJSONFromUrl（url）；
试一试{
//获取联系人数组
//contacts=json.getJSONArray（TAG_contacts）；
//通过所有触点循环
对于（int i=0；ivalue
地图放置（标签名称、名称）；
地图放置（标签图片，图片）；
地图放置（标记日期、日期）；
//将哈希列表添加到ArrayList
联系人列表。添加（地图）；
}
}捕获（JSONException e）{
e、 printStackTrace（）；
}
/**
*将解析的JSON数据更新到ListView中
* */
ListAdapter=新的SimpleAdapter（此，contactList，
R.layout.list_项目，
新字符串[]{TAG_NAME，TAG_Date}，新int[]{
R.id.name、R.id.email、R.id.mobile}）；
setListAdapter（适配器）；
//选择单个ListView项
ListView lv=getListView（）；
//在选择单个列表项时启动新屏幕
lv.setOnItemClickListener（新的OnItemClickListener（）{
@凌驾
public void onItemClick（AdapterView父级、视图、，
内部位置，长id）{
//从选定的ListItem获取值
字符串名称=（（TextView）view.findviewbyd（R.id.name））.getText（）.toString（）；
字符串成本=（（TextView）view.findViewById（R.id.email））.getText（）.toString（）；
字符串描述=（（TextView）view.findviewbyd（R.id.mobile））.getText（）.toString（）；
//开始新的意图
Intent in=新的Intent（getApplicationContext（），SingleMenuItemActivity.class）；
in.putExtra（标签名称、名称）；
in.putExtra（标签日期、说明）；
星触觉（in）；
}
});
}
}
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
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() {
}
public JSONObject getJSONFromUrl(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
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;
}
}
public class AndroidJSONParsingActivity extends ListActivity {
// url to make request
private static String url = "http://api.androidhive.info/contacts/";
// JSON Node names
private static final String TAG_CONTACTS = "contacts";
private static final String TAG_ID = "id";
private static final String TAG_NAME = "name";
private static final String TAG_EMAIL = "email";
private static final String TAG_ADDRESS = "address";
private static final String TAG_GENDER = "gender";
private static final String TAG_PHONE = "phone";
private static final String TAG_PHONE_MOBILE = "mobile";
private static final String TAG_PHONE_HOME = "home";
private static final String TAG_PHONE_OFFICE = "office";
// contacts JSONArray
JSONArray contacts = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Hashmap for ListView
ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONObject json = jParser.getJSONFromUrl(url);
try {
// Getting Array of Contacts
contacts = json.getJSONArray(TAG_CONTACTS);
// looping through All Contacts
for(int i = 0; i < contacts.length(); i++){
JSONObject c = contacts.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_ID);
String name = c.getString(TAG_NAME);
String email = c.getString(TAG_EMAIL);
String address = c.getString(TAG_ADDRESS);
String gender = c.getString(TAG_GENDER);
// Phone number is agin JSON Object
JSONObject phone = c.getJSONObject(TAG_PHONE);
String mobile = phone.getString(TAG_PHONE_MOBILE);
String home = phone.getString(TAG_PHONE_HOME);
String office = phone.getString(TAG_PHONE_OFFICE);
// 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_NAME, name);
map.put(TAG_EMAIL, email);
map.put(TAG_PHONE_MOBILE, mobile);
// adding HashList to ArrayList
contactList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, contactList,
R.layout.list_item,
new String[] { TAG_NAME, TAG_EMAIL, TAG_PHONE_MOBILE }, new int[] {
R.id.name, R.id.email, R.id.mobile });
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 name = ((TextView) view.findViewById(R.id.name)).getText().toString();
String cost = ((TextView) view.findViewById(R.id.email)).getText().toString();
String description = ((TextView) view.findViewById(R.id.mobile)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
in.putExtra(TAG_NAME, name);
in.putExtra(TAG_EMAIL, cost);
in.putExtra(TAG_PHONE_MOBILE, description);
startActivity(in);
}
});
}
}
公共类AndroidJSONParsingActivity扩展了ListActivity{
//发出请求的url
专用静态字符串url=”http://api.androidhive.info/contacts/";
//JSON节点名称
专用静态最终字符串标记_CONTACTS=“CONTACTS”；
私有静态最终字符串标记\u ID=“ID”；
私有静态最终字符串标记_NAME=“NAME”；
私有静态最终字符串标记\u EMAIL=“EMAIL”；
私有静态最终字符串标记_ADDRESS=“ADDRESS”；
私有静态最终字符串标记_GENDER=“GENDER”；
专用静态最终字符串标记_PHONE=“PHONE”；
专用静态最终字符串标记\u PHONE\u MOBILE=“MOBILE”；
专用静态最终字符串标记\u PHONE\u HOME=“HOME”；
专用静态最终字符串标记\u PHONE\u OFFICE=“OFFICE”；
//联系JSONArray
JSONArray联系人=null；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
//ListView的Hashmap
ArrayList contactList=新建ArrayList（）；
//创建JSON解析器实例
JSONParser jParser=新的JSONParser（）；
//从URL获取JSON字符串
JSONObject json=jParser.getJSONFromUrl（url）；
试一试{
//获取联系人数组
contacts=json.getJSONArray（TAG_contacts）；
//通过所有触点循环
对于（int i=0；ivalue
地图放置（标签标识，标识）；
地图