痞客興的部落格

AndroidManifest.xml裡要開放對INTERNET的存取權限
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.charleslin.jsontest" >
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
        <activity
android:name=".MainActivity"
android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <categoryandroid:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

建立一個JsonParser.java程式,將網路JSON URL讀取內容後進行資料處理,此程式將提供給主程式呼叫

package com.example.charleslin.jsontest;

import android.util.Log;

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 java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;

/**
 * Created by charleslin on 2015/9/13.
 */
public class JsonParser {

    final String TAG = "JsonParser.java";

static InputStream is = null;
static JSONObject jObj = null;
static String json = "";

public JSONObject getJSONFromUrl(String url) {

        // make HTTP request
try {

            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, "UTF-8"), 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(TAG, "Error converting result " + e.toString());
}

        // try parse the string to a JSON object
try {
            jObj = new JSONObject(json);
} catch (JSONException e) {
            Log.e(TAG, "Error parsing data " + e.toString());
}

        // return JSON String
return jObj;
}
}

MainActivity.java將會呼叫JsonParser.java來讀取JSON URL的內容,分析後將顯示在Log上

package com.example.charleslin.jsontest;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;


public class MainActivity extends Activity {

    @Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

new AsyncTaskParseJson().execute();

}

    public class AsyncTaskParseJson extends AsyncTask<String, String, String> {

        final String TAG = "AsyncTaskParseJson.java";

// set your json string url here
String yourJsonStringUrl = "http://charleslin74.esy.es/contact/index.php";

// contacts JSONArray
JSONArray dataJsonArr = null;

@Override
protected void onPreExecute() {}

        @Override
protected String doInBackground(String... arg0) {

            try {

                // instantiate our json parser
JsonParser jParser = new JsonParser();

// get json string from url
JSONObject json = jParser.getJSONFromUrl(yourJsonStringUrl);

// get the array of users
dataJsonArr = json.getJSONArray("KHtravel");

// loop through all users
for (int i = 0; i < dataJsonArr.length(); i++) {

                    JSONObject c = dataJsonArr.getJSONObject(i);

// Storing each json item in variable
String id = c.getString("id");
String name = c.getString("name");
//String username = c.getString("username");

                    // show the values in our logcat
Log.e(TAG, "id: " + id
                            + ", name: " + name);

}

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

            return null;
}

        @Override
protected void onPostExecute(String strFromDoInBg) {}
    }

    @Override
public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}

    @Override
public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();

//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
            return true;
}

        return super.onOptionsItemSelected(item);
}
}

結果顯示如下

本文參考https://www.codeofaninja.com/2013/11/android-json-parsing-tutorial.html