Android 获取 json
MainActivity.java
package com.example.jsontest;
import java.io.IOException;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
public TextView myTextView = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.setContentView(R.layout.activity_main);
this.myTextView=(TextView) findViewById(R.id.textView1);
Button btn = (Button)this.findViewById(R.id.button1);
btn.setOnClickListener(new Button.OnClickListener(){
@Override
public void onClick(View v) {
try{
new ReadHttpGet().execute("http://192.168.1.31/json.js");
}catch(Exception e){
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
class ReadHttpGet extends AsyncTask<Object, Object, Object>
{
@Override
protected Object doInBackground(Object... params) {
// TODO Auto-generated method stub
HttpGet httpRequest = new HttpGet(params[0].toString());
try
{
HttpClient httpClient = new DefaultHttpClient();
HttpResponse httpResponse = httpClient.execute(httpRequest);
if(httpResponse.getStatusLine().getStatusCode() == HttpStatus.SC_OK)
{
String strResult = EntityUtils.toString(httpResponse.getEntity());
return strResult;
}
else
{
return "请求出错";
}
}
catch(ClientProtocolException e)
{
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
@SuppressLint("NewApi")
@Override
protected void onCancelled(Object result) {
// TODO Auto-generated method stub
super.onCancelled(result);
}
@Override
protected void onPostExecute(Object result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
try
{
//创建一个JSON对象
//JSONObject jsonObject = new JSONObject(result.toString()).getJSONObject("parent");
//获取某个对象的JSON数组
JSONArray jsonArray = new JSONArray(result.toString());
StringBuilder builder = new StringBuilder();
for(int i = 0; i<jsonArray.length(); i++)
{
//新建一个JSON对象，该对象是某个数组里的其中一个对象
JSONObject jsonObject2 = (JSONObject)jsonArray.opt(i);
builder.append(jsonObject2.getString("id")); //获取数据
builder.append(jsonObject2.getString("title"));
builder.append(jsonObject2.getString("name"));
}
myTextView.setText(builder.toString());
}
catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
//super.onPreExecute();
Toast.makeText(getApplicationContext(), "开始HTTP GET请求", Toast.LENGTH_LONG).show();
}
@Override
protected void onProgressUpdate(Object... values) {
// TODO Auto-generated method stub
super.onProgressUpdate(values);
}
}
}
activity_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.jsontest.MainActivity"
tools:ignore="MergeRootFrame" >
<TextView
android:id="@+id/textView1"
android:layout_width="match_parent"
android:layout_height="174dp"
android:text="TextView" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="get" />
</FrameLayout>
AndroidManifest.xml 加上网络权限： <uses-permission android:name="android.permission.INTERNET" />