如何解析子JSONArray和显示图像？ [英] How to parse Sub JSONArray and display image?
本文介绍了如何解析子JSONArray和显示图像？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
我是一个PHP程序员，我努力学习JAVA。 我有问题，试图解析一个JSON文件。它已经为3 days..having头疼这个。 我创建一个Android应用程序（使用Java）来解析JSON文件。 这是样本JSON数据（ http://metalgearrisingguide.com/samplejson.json ） 而如何显示图像？
当我尝试，我都显示在仿真器下面的错误在我的logcat并没有什么
错误解析数据org.json.JSONException：值{产品：[{总结：讲一个字和旋钮将转由itself","state":"good","image":"http:\/\/upload.wikimedia.org\/wikipedia\/commons\/e\/e9\/Door_Knob_with_Lock_USA.jpg","title":"Special门把手无需控股只是音乐，地址：[{地址：商家地址1}，{地址：商家地址2}]，URL：HTTP：\ / \ / merchantwebsite.com}，{总结：这门钟会检测已知的人脸，如果变音乐unknown","state":"good","image":"http:\/\/www.thedoorbell.net\/images\/DoorbellHeader.jpg","title":"Special它使用脸部识别技术门铃，地址：[{地址：商家地址1}，{地址：商家地址2}]，URL：HTTP：\ / \ / merchantwebsite2.com}，{总结：无法在清晨醒来\ r \ nWill你保持清醒党听您喜欢的歌曲，将唤醒？ you!","state":"refurnished","image":"http:\/\/jgrundig.wpengine.netdna-cdn.com\/wp-content\/uploads\/2011\/08\/RCA-Alarm-Clock-with-Charging-Cord-RC107.jpg","title":"The只有闹钟可以播放您喜爱的歌曲从你的智能手机，地址：[{地址：商家地址1}，{地址：商家地址2}]，URL：HTTP： \ / \ / merchantwebsite3.com}]，现场：{网站名称：简单的产品寻找，IMG preFIX：HTTP：\ / \ / mydomain.com \ /，网址preFIX：的http：\ / \ / mydomain.com \ /}}在类型org.json.JSONObject的数据不能被转换为JSONArray
下面是我的JSONfunctions类：
公共类JSONfunctions {
公共静态的JSONObject getJSONfromURL（字符串URL）{
InputStream的是= NULL;
字符串结果=;
JSONObject的jArray = NULL;
// HTTP POST
尝试{
HttpClient的HttpClient的=新DefaultHttpClient（）;
HttpPost httppost =新HttpPost（URL）;
HTT presponse响应= httpclient.execute（httppost）;
HttpEntity实体= response.getEntity（）;
是= entity.getContent（）;
}赶上（例外五）{
Log.e（log_tag，错误的HTTP连接+ e.toString（））;
}
//转换响应串
尝试{
的BufferedReader读卡器=新的BufferedReader（新InputStreamReader的（就是，ISO-8859-1），8）;
StringBuilder的SB =新的StringBuilder（）;
串线= NULL;
而（（行= reader.readLine（））！= NULL）{
sb.append（行+\ N）;
}
is.close（）;
结果= sb.toString（）;
}赶上（例外五）{
Log.e（log_tag，错误转换结果+ e.toString（））;
}
尝试{
jArray =新的JSONObject的（结果）;
}赶上（JSONException E）{
Log.e（log_tag，错误分析数据+ e.toString（））;
}
返回jArray;
//返回结果;
}
}
和这里是我的code：
公共类主要扩展ListActivity {
/ **第一次创建活动时调用。 * /
@覆盖
公共无效的onCreate（包savedInstanceState）{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.listplaceholder）;
ArrayList的＆LT; HashMap的＆LT;字符串，字符串＆GT;＆GT; mylist中=新的ArrayList＆LT; HashMap的＆LT;字符串，字符串＆GT;＆GT;（）;
JSONObject的JSON = JSONfunctions.getJSONfromURL（http://metalgearrisingguide.com/samplejson.json）;
尝试{
JSONArray数据= json.getJSONArray（数据）;
JSONArray产品= data.getJSONArray（1）;
的for（int i = 0; I＆LT; products.length（）;我++）{
HashMap的＆LT;字符串，字符串＆GT;图=新的HashMap＆LT;字符串，字符串＆GT;（）;
JSONObject的E = products.getJSONObject（我）;
map.put（ID，将String.valueOf（I））;
map.put（标题，产品名称：+ e.getString（标题））;
map.put（国家，条件：+ e.getString（国家））;
map.put（摘要，描述：+ e.getString（摘要））;
mylist.add（图）
设置设置= map.entrySet（）;
//获取一个迭代器
迭代器O = set.iterator（）;
//显示元件
而（o.hasNext（））{
Map.Entry的我=（Map.Entry的）o.next（）;
System.out.print（me.getKey（）+：）;
的System.out.println（me.getValue（））;
}
的System.out.println（）;
}
}赶上（JSONException E）{
Log.e（log_tag，错误分析数据+ e.toString（））;
}
ListAdapter适配器=新SimpleAdapter（这一点，mylist中，R.layout.main，
新的String [] {状态，摘要}，
新的INT [] {R.id.item_title，R.id.item_subtitle}）;
setListAdapter（适配器）;
最终的ListView LV = getListView（）;
lv.setTextFilterEnabled（真正的）;
lv.setOnItemClickListener（新OnItemClickListener（）{
公共无效onItemClick（适配器视图＆LT;＆GT;母公司视图中查看，INT位置，长的id）{
@燮pressWarnings（未登记）
HashMap的＆LT;字符串，字符串＆GT; O =（HashMap的＆LT;字符串，字符串＆GT;）lv.getItemAtPosition（位置）;
Toast.makeText（Main.this，ID+ o.get（ID）+'被点击了。，Toast.LENGTH_SHORT）.show（）;
}
}）;
}
}
解决方案
您方舟两个问题，第一，如何解析子JSON;第二，如何显示从净图像;我做了一个成功的演示你的样品JSON的网址如下：
首先，定义一个数据类：Data.java
包com.example.jsonparser;
进口的java.util.ArrayList;
公共类数据{
私人字符串mState;
私人字符串mImageUrl;
私人字符串mTitle;
私人字符串mSummary;
私人的ArrayList＆LT;字符串＆GT; mAddList;
私人字符串mUrl;
公开数据（字符串mState，字符串mImageUrl，字符串mTitle，
字符串mSummary，ArrayList的＆LT;字符串＆GT; addList，串mUrl）{
超（）;
this.mState = mState;
this.mImageUrl = mImageUrl;
this.mTitle = mTitle;
this.mSummary = mSummary;
this.mAddList = addList;
this.mUrl = mUrl;
}
公共字符串getmState（）{
返回mState;
}
公共无效setmState（字符串mState）{
this.mState = mState;
}
公共字符串getmImageUrl（）{
返回mImageUrl;
}
公共无效setmImageUrl（字符串mImageUrl）{
this.mImageUrl = mImageUrl;
}
公共字符串getmTitle（）{
返回mTitle;
}
公共无效setmTitle（字符串mTitle）{
this.mTitle = mTitle;
}
公共字符串getmSummary（）{
返回mSummary;
}
公共无效setmSummary（字符串mSummary）{
this.mSummary = mSummary;
}
公众的ArrayList＆LT;字符串＆GT; getmAddress1（）{
返回mAddList;
}
公共无效setmAddress1（ArrayList中＆LT;字符串＆GT; mAddress1）{
this.mAddList = mAddress1;
}
公共字符串getmUrl（）{
返回mUrl;
}
公共无效setmUrl（字符串mUrl）{
this.mUrl = mUrl;
}
}
二，定义一个解析器类解析JSON字符串：Parser.java
包com.example.jsonparser;
进口的java.util.ArrayList;
进口org.json.JSONArray;
进口org.json.JSONException;
进口org.json.JSONObject;
进口android.util.Log;
公共类解析器{
私人的ArrayList＆lt;数据＆GT; mDataSource =新的ArrayList＆lt;数据＆GT;（）;
公共分析器（JSON字符串）{
jsonParser（JSON）;
}
私人无效jsonParser（JSON字符串）{
尝试 {
JSONObject的OBJ =新的JSONObject（JSON）;
JSONObject的VAR = obj.getJSONObject（数据）;
JSONArray列表= var.getJSONArray（产品）;
INT的len = list.length（）;
的for（int i = 0; I＆LT; LEN;我++）{
尝试 {
JSONObject的数据= list.getJSONObject（我）;
字符串状态= data.getString（国家）;
字符串图像= data.getString（图像）;
字符串标题= data.getString（标题）;
字符串摘要= data.getString（摘要）;
字符串URL = data.getString（URL）;
ArrayList的＆LT;字符串＆GT; addList =新的ArrayList＆LT;字符串＆GT;（）;
JSONArray addArray = data.getJSONArray（地址）;
INT大小= addArray.length（）;
/ **
*解析器子JSON
* /
对于（INT J = 0; J＆LT;大小; J ++）{
addList.add（addArray.getJSONObject（J）.getString（地址））;
}
mDataSource.add（新数据（状态，图片，标题，摘要，addList，URL））;
}赶上（JSONException E）{
// TODO自动生成的catch块
e.printStackTrace（）;
}
}
}赶上（JSONException E）{
// TODO自动生成的catch块
e.printStackTrace（）;
}
}
公众的ArrayList＆lt;数据＆GT;的getSource（）{
返回mDataSource;
}
}
第三，通过URL定义任务下载图片：DownloadImageTask.java
包com.example.jsonparser;
进口java.io.IOException异常;
进口的java.io.InputStream;
进口java.net.HttpURLConnection中;
进口java.net.MalformedURLException;
进口的java.net.URL;
进口android.graphics.Bitmap;
进口android.graphics.BitmapFactory;
进口android.os.AsyncTask;
进口android.widget.ImageView;
公共类DownloadImageTask扩展的AsyncTask＆LT;虚空，虚空，位图＆GT; {
私人字符串mUrl;
私人ImageView的mImageView = NULL;
公共DownloadImageTask（字符串的URL，ImageView的ImageView的）{
mUrl =网址;
this.mImageView = ImageView的;
}
保护无效onPostExecute（位图的结果）{
super.onPostExecute（结果）;
如果（结果！= NULL）{
mImageView.setImageBitmap（结果）;
}
}
受保护的位图doInBackground（空... PARAMS）{
点阵位图= getBitmap（mUrl）;
返回的位图;
}
公共位图getBitmap（字符串IMAGEURL）{
位图mBitmap = NULL;
尝试 {
网址URL =新的URL（IMAGEURL）;
HttpURLConnection的康恩=（HttpURLConnection类）url.openConnection（）;
InputStream的是= conn.getInputStream（）;
mBitmap = BitmapFactory.de codeStream（是）;
}赶上（MalformedURLException异常E）{
e.printStackTrace（）;
}赶上（IOException异常E）{
e.printStackTrace（）;
}
返回mBitmap;
}
}
第四，定义一个接口扩展BaseAdapter显示的数据和图像：Adapter.java
包com.example.jsonparser;
进口的java.util.ArrayList;
进口android.app.Activity;
进口android.view.LayoutInflater;
进口android.view.View;
进口android.view.ViewGroup;
进口android.widget.AbsListView;
进口android.widget.AbsListView.RecyclerListener;
进口android.widget.BaseAdapter;
进口android.widget.ImageView;
进口android.widget.TextView;
公共类适配器扩展了BaseAdapter {
私有静态最后字符串变量=适配器;
私人活动mActivity;
公众的ArrayList＆lt;数据＆GT; mObjects;
静态类ViewHolder {
ImageView的图标;
TextView的称号;
DownloadImageTask mTask;
}
公共适配器（活动活动，ArrayList的＆lt;数据＆GT; mObjects）{
this.mActivity =（活动）的活动;
this.mObjects = mObjects;
}
公共无效setObjects（ArrayList的＆lt;数据＆GT; mObjects）{
this.mObjects = mObjects;
}
@覆盖
公共查看getView（INT位置，查看convertView，ViewGroup中父）{
数据项= mObjects.get（位置）;
查看rowView = convertView;
如果（rowView == NULL）{
LayoutInflater充气= mActivity.getLayoutInflater（）;
rowView = inflater.inflate（R.layout.item，父母，假）;
ViewHolder viewHolder =新ViewHolder（）;
viewHolder.icon =（ImageView的）rowView.findViewById（R.id.image）;
viewHolder.title =（TextView中）rowView.findViewById（R.id.title）;
rowView.setTag（viewHolder）;
}
ViewHolder支架=（ViewHolder）rowView.getTag（）;
holder.title.setText（item.getmTitle（））;
holder.icon.setBackgroundResource（R.drawable.ic_launcher）;
holder.mTask =新DownloadImageTask（item.getmImageUrl（），holder.icon）;
如果（！holder.mTask.isCancelled（））{
holder.mTask.execute（）;
}
返回rowView;
}
@覆盖
公众诠释getCount将（）{
返程（this.mObjects.size（））;
}
@覆盖
公共对象的getItem（INT位置）{
返程（this.mObjects.get（位置））;
}
@覆盖
众长getItemId（INT位置）{
返回（位置）;
}
公共AbsListView.RecyclerListener mRecyclerListener =新RecyclerListener（）{
公共无效onMovedToScrapHeap（查看视图）{
ViewHolder viewHolder =（ViewHolder）view.getTag（）;
DownloadImageTask imagetask = viewHolder.mTask;
如果（imagetask！= NULL）{
imagetask.cancel（真正的）;
}
}
};
}
最后，在活动中使用这些类：MainActivity.java
包com.example.jsonparser;
进口java.io.BufferedReader中;
进口的java.io.InputStream;
进口java.io.InputStreamReader中;
进口的java.util.ArrayList;
进口org.apache.http.HttpEntity;
进口org.apache.http.Htt presponse;
进口org.apache.http.client.HttpClient;
进口org.apache.http.client.methods.HttpPost;
进口org.apache.http.impl.client.DefaultHttpClient;
进口android.app.Activity;
进口android.os.Bundle;
进口android.os.Handler;
进口android.os.Message;
进口android.util.Log;
进口android.widget.ListView;
公共类MainActivity延伸活动{
私人的ListView mListView;
专用适配器mAdapter;
私人的ArrayList＆lt;数据＆GT; mSource =新的ArrayList＆lt;数据＆GT;（）;
@覆盖
保护无效的onCreate（包savedInstanceState）{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.activity_main）;
mListView =（ListView控件）findViewById（android.R.id.list）;
mAdapter =新的适配器（这一点，mSource）;
mListView.setAdapter（mAdapter）;
mListView.setRecyclerListener（mAdapter.mRecyclerListener）;
最终的字符串URL =http://metalgearrisingguide.com/samplejson.json;
新主题（新的Runnable（）{
@覆盖
公共无效的run（）{
分析器分析器=新的解析器（getJSONfromURL（URL））;
mSource = parser.getSource（）;
消息味精= mHandler.obtainMessage（）;
mHandler.sendMessage（MSG）;
}
}）。开始（）;
}
私人处理程序mHandler =新的处理程序（）{
@覆盖
公共无效的handleMessage（信息MSG）{
mAdapter.setObjects（mSource）;
mAdapter.notifyDataSetChanged（）;
}
};
公共字符串getJSONfromURL（字符串URL）{
InputStream的是= NULL;
字符串结果=;
// HTTP POST
尝试 {
HttpClient的HttpClient的=新DefaultHttpClient（）;
HttpPost httppost =新HttpPost（URL）;
HTT presponse响应= httpclient.execute（httppost）;
HttpEntity实体= response.getEntity（）;
是= entity.getContent（）;
}赶上（例外五）{
Log.e（log_tag，错误的HTTP连接+ e.toString（））;
}
//转换响应串
尝试 {
的BufferedReader读卡器=新的BufferedReader（新的InputStreamReader（
是，ISO-8859-1），8）;
StringBuilder的SB =新的StringBuilder（）;
串线= NULL;
而（（行= reader.readLine（））！= NULL）{
sb.append（行+\ N）;
}
is.close（）;
结果= sb.toString（）;
}赶上（例外五）{
Log.e（log_tag，错误转换结果+ e.toString（））;
}
返回结果;
}
}
activity_main.xml
＆LT; LinearLayout中的xmlns：机器人=http://schemas.android.com/apk/res/android
的xmlns：工具=http://schemas.android.com/tools
机器人：layout_width =match_parent
机器人：layout_height =match_parent
工具：上下文=MainActivity。＆GT;
＆LT;的ListView
机器人：ID =@机器人：ID /列表
机器人：layout_width =match_parent
机器人：layout_height =match_parent
机器人：cacheColorHint =@机器人：彩色/透明/＆GT;
＆LT; / LinearLayout中＆GT;
item.xml
＆LT; XML版本=1.0编码=UTF-8＆GT？;
＆LT; LinearLayout中的xmlns：机器人=http://schemas.android.com/apk/res/android
机器人：layout_width =match_parent
机器人：layout_height =WRAP_CONTENT
机器人：方向=横向＆GT;
＆LT; ImageView的
机器人：ID =@ + ID /图像
机器人：layout_width =40dp
机器人：layout_height =40dp
机器人：layout_gravity =左|顶
机器人：layout_marginBottom =10dp
机器人：layout_marginLeft =10dp
机器人：layout_marginTop =10dp/＆GT;
＆LT;的TextView
机器人：ID =@ + ID /标题
机器人：layout_width =WRAP_CONTENT
机器人：layout_height =WRAP_CONTENT
机器人：ellipsize =结束
机器人：重力=左|顶
机器人：lineSpacingExtra =3.0dp
机器人：文字颜色=＃FFFFFF
机器人：TEXTSIZE =15sp/＆GT;
＆LT; / LinearLayout中＆GT;
这就是全部。
I am a php programmer and I am trying to learn JAVA. I have problem trying to parse a json file. It's been for 3 days..having a headache at this. I am create an android application (using JAVA) to parse json file. This is the sample json data (http://metalgearrisingguide.com/samplejson.json) And how to display the image?
When i tried, I have the following error at my logcat and nothing is displayed on the emulator
Error parsing data org.json.JSONException: Value {"product":[{"summary":"Speak a word and the knob will turn by itself","state":"good","image":"http:\/\/upload.wikimedia.org\/wikipedia\/commons\/e\/e9\/Door_Knob_with_Lock_USA.jpg","title":"Special Door knob requires no holding just music","address":[{"address":"Merchant address 1"},{"address":"merchant address 2"}],"url":"http:\/\/merchantwebsite.com"},{"summary":"This door bell will detect faces of known people and change music if unknown","state":"good","image":"http:\/\/www.thedoorbell.net\/images\/DoorbellHeader.jpg","title":"Special Door Bell that uses face recognition technology","address":[{"address":"Merchant address 1"},{"address":"merchant address 2"}],"url":"http:\/\/merchantwebsite2.com"},{"summary":"Can't wake up in the morning?\r\nWill you be awake for party? Listen to your favourite song that will awake you!","state":"refurnished","image":"http:\/\/jgrundig.wpengine.netdna-cdn.com\/wp-content\/uploads\/2011\/08\/RCA-Alarm-Clock-with-Charging-Cord-RC107.jpg","title":"The only alarm clock that plays your favourite song from your smartphone","address":[{"address":"Merchant address 1"},{"address":"merchant address 2"}],"url":"http:\/\/merchantwebsite3.com"}],"site":{"sitename":"Simple Product Find","imgprefix":"http:\/\/mydomain.com\/","urlprefix":"http:\/\/mydomain.com\/"}} at data of type org.json.JSONObject cannot be converted to JSONArray
Here is my JSONfunctions class:
public class JSONfunctions {
public static JSONObject getJSONfromURL(String url){
InputStream is = null;
String result = "";
JSONObject jArray = null;
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
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);
StringBuilder sb = new StringBuilder();
String line = null;
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());
}
try{
jArray = new JSONObject(result);
}catch(JSONException e){
Log.e("log_tag", "Error parsing data "+e.toString());
}
return jArray;
//return result;
}
}
And here is my code:
public class Main extends ListActivity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listplaceholder);
ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
JSONObject json = JSONfunctions.getJSONfromURL("http://metalgearrisingguide.com/samplejson.json");
try{
JSONArray data = json.getJSONArray("data");
JSONArray products = data.getJSONArray(1);
for(int i=0;i<products.length();i++){
HashMap<String, String> map = new HashMap<String, String>();
JSONObject e = products.getJSONObject(i);
map.put("id", String.valueOf(i));
map.put("title", "Product name:" + e.getString("title"));
map.put("state", "Condition:" + e.getString("state"));
map.put("summary", "Description: " + e.getString("summary"));
mylist.add(map);
Set set = map.entrySet();
// Get an iterator
Iterator o = set.iterator();
// Display elements
while(o.hasNext()) {
Map.Entry me = (Map.Entry)o.next();
System.out.print(me.getKey() + ": ");
System.out.println(me.getValue());
}
System.out.println();
}
}catch(JSONException e) {
Log.e("log_tag", "Error parsing data "+e.toString());
}
ListAdapter adapter = new SimpleAdapter(this, mylist , R.layout.main,
new String[] { "state", "summary" },
new int[] { R.id.item_title, R.id.item_subtitle });
setListAdapter(adapter);
final ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
@SuppressWarnings("unchecked")
HashMap<String, String> o = (HashMap<String, String>) lv.getItemAtPosition(position);
Toast.makeText(Main.this, "ID '" + o.get("id") + "' was clicked.", Toast.LENGTH_SHORT).show();
}
});
}
}
解决方案
You ark two questions, the first, how to parse the sub json; second, how to display image from the net; I made a successful demo by your sample json url as follows:
First, define a data class: Data.java
package com.example.jsonparser;
import java.util.ArrayList;
public class Data {
private String mState;
private String mImageUrl;
private String mTitle;
private String mSummary;
private ArrayList<String> mAddList;
private String mUrl;
public Data(String mState, String mImageUrl, String mTitle,
String mSummary, ArrayList<String> addList, String mUrl) {
super();
this.mState = mState;
this.mImageUrl = mImageUrl;
this.mTitle = mTitle;
this.mSummary = mSummary;
this.mAddList = addList;
this.mUrl = mUrl;
}
public String getmState() {
return mState;
}
public void setmState(String mState) {
this.mState = mState;
}
public String getmImageUrl() {
return mImageUrl;
}
public void setmImageUrl(String mImageUrl) {
this.mImageUrl = mImageUrl;
}
public String getmTitle() {
return mTitle;
}
public void setmTitle(String mTitle) {
this.mTitle = mTitle;
}
public String getmSummary() {
return mSummary;
}
public void setmSummary(String mSummary) {
this.mSummary = mSummary;
}
public ArrayList<String> getmAddress1() {
return mAddList;
}
public void setmAddress1(ArrayList<String> mAddress1) {
this.mAddList = mAddress1;
}
public String getmUrl() {
return mUrl;
}
public void setmUrl(String mUrl) {
this.mUrl = mUrl;
}
}
Second, define a parser class for parsing the json string: Parser.java
package com.example.jsonparser;
import java.util.ArrayList;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.util.Log;
public class Parser {
private ArrayList<Data> mDataSource = new ArrayList<Data>();
public Parser(String json) {
jsonParser(json);
}
private void jsonParser(String json) {
try {
JSONObject obj = new JSONObject(json);
JSONObject var = obj.getJSONObject("data");
JSONArray list = var.getJSONArray("product");
int len = list.length();
for (int i = 0; i < len; i++) {
try {
JSONObject data = list.getJSONObject(i);
String state = data.getString("state");
String image = data.getString("image");
String title = data.getString("title");
String summary = data.getString("summary");
String url = data.getString("url");
ArrayList<String> addList = new ArrayList<String>();
JSONArray addArray = data.getJSONArray("address");
int size = addArray.length();
/**
* parser sub json
*/
for(int j = 0; j < size; j++) {
addList.add(addArray.getJSONObject(j).getString("address"));
}
mDataSource.add(new Data(state, image, title, summary, addList, url));
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public ArrayList<Data> getSource() {
return mDataSource;
}
}
Third, define a task download image by url: DownloadImageTask.java
package com.example.jsonparser;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.widget.ImageView;
public class DownloadImageTask extends AsyncTask<Void, Void, Bitmap> {
private String mUrl;
private ImageView mImageView = null;
public DownloadImageTask(String Url, ImageView imageView) {
mUrl = Url;
this.mImageView = imageView;
}
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
if (result != null) {
mImageView.setImageBitmap(result);
}
}
protected Bitmap doInBackground(Void... params) {
Bitmap bitmap = getBitmap(mUrl);
return bitmap;
}
public Bitmap getBitmap(String imageUrl) {
Bitmap mBitmap = null;
try {
URL url = new URL(imageUrl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
InputStream is = conn.getInputStream();
mBitmap = BitmapFactory.decodeStream(is);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return mBitmap;
}
}
Forth, define a adapter extend BaseAdapter for displaying the data and image: Adapter.java
package com.example.jsonparser;
import java.util.ArrayList;
import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AbsListView.RecyclerListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class Adapter extends BaseAdapter {
private static final String TAG = "Adapter";
private Activity mActivity;
public ArrayList<Data> mObjects;
static class ViewHolder {
ImageView icon;
TextView title;
DownloadImageTask mTask;
}
public Adapter(Activity activity, ArrayList<Data> mObjects) {
this.mActivity = (Activity) activity;
this.mObjects = mObjects;
}
public void setObjects(ArrayList<Data> mObjects) {
this.mObjects = mObjects;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Data item = mObjects.get(position);
View rowView = convertView;
if (rowView == null) {
LayoutInflater inflater = mActivity.getLayoutInflater();
rowView = inflater.inflate(R.layout.item, parent, false);
ViewHolder viewHolder = new ViewHolder();
viewHolder.icon = (ImageView) rowView.findViewById(R.id.image);
viewHolder.title = (TextView) rowView.findViewById(R.id.title);
rowView.setTag(viewHolder);
}
ViewHolder holder = (ViewHolder) rowView.getTag();
holder.title.setText(item.getmTitle());
holder.icon.setBackgroundResource(R.drawable.ic_launcher);
holder.mTask = new DownloadImageTask(item.getmImageUrl(), holder.icon);
if (!holder.mTask.isCancelled()) {
holder.mTask.execute();
}
return rowView;
}
@Override
public int getCount() {
return (this.mObjects.size());
}
@Override
public Object getItem(int position) {
return (this.mObjects.get(position));
}
@Override
public long getItemId(int position) {
return (position);
}
public AbsListView.RecyclerListener mRecyclerListener = new RecyclerListener( ){
public void onMovedToScrapHeap(View view) {
ViewHolder viewHolder = (ViewHolder) view.getTag();
DownloadImageTask imagetask = viewHolder.mTask;
if (imagetask != null) {
imagetask.cancel(true);
}
}
};
}
The last, use these class in activity: MainActivity.java
package com.example.jsonparser;
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.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.widget.ListView;
public class MainActivity extends Activity {
private ListView mListView;
private Adapter mAdapter;
private ArrayList<Data> mSource = new ArrayList<Data>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mListView = (ListView) findViewById(android.R.id.list);
mAdapter = new Adapter(this, mSource);
mListView.setAdapter(mAdapter);
mListView.setRecyclerListener(mAdapter.mRecyclerListener);
final String url = "http://metalgearrisingguide.com/samplejson.json";
new Thread(new Runnable() {
@Override
public void run() {
Parser parser = new Parser(getJSONfromURL(url));
mSource = parser.getSource();
Message msg = mHandler.obtainMessage();
mHandler.sendMessage(msg);
}
}).start();
}
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
mAdapter.setObjects(mSource);
mAdapter.notifyDataSetChanged();
}
};
public String getJSONfromURL(String url) {
InputStream is = null;
String result = "";
// http post
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
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);
StringBuilder sb = new StringBuilder();
String line = null;
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());
}
return result;
}
}
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<ListView
android:id="@android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:cacheColorHint="@android:color/transparent" />
</LinearLayout>
item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<ImageView
android:id="@+id/image"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_gravity="left|top"
android:layout_marginBottom="10dp"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp" />
<TextView
android:id="@+id/title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ellipsize="end"
android:gravity="left|top"
android:lineSpacingExtra="3.0dp"
android:textColor="#ffffff"
android:textSize="15sp" />
</LinearLayout>
that's all.
这篇关于如何解析子JSONArray和显示图像？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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