How to parse json in android
JSON is very light weight, structured, easy to parse and much human readable. JSON is best alternative to XML when your android app needs to interchange data with your server.
In this tutorial we are going to learn how to parse JSON in android using different ways, using java.net library and other third part libraries.
In This Tutorial We Can Parse A Simple Json Data Which Shows The Name Of The Cities From The Server
I use My Own Created JSON File Which is Live On The Server U See By Click On The Url Shown Below
AndroidManifest.xml
In This File We Have To Insert An Permission Of Internet
"<uses-permission android:name="android.permission.INTERNET"/>"
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.tushar.jsonparsing">
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".button"/>
</application>
</manifest>
HttpHandler.java
In This Class We Make Service Call() Makes HTTP Call To Particular Url And Fetches The Cities Name
package com.tushar.jsonparsing;
import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
/** * Created by Lenovo on 7/29/2017. */
public class HttpHandler {
private static final String TAG = HttpHandler.class.getSimpleName();
public HttpHandler(){}
public String makeServiceCall(String reqUrl){
String response = null;
try {
URL url = new URL(reqUrl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
InputStream in = new BufferedInputStream(connection.getInputStream());
response = convertStreamToString(in);
} catch (MalformedURLException e) {
e.printStackTrace();
}
catch (IOException e){
e.printStackTrace();
}
return response;
}
private String convertStreamToString(InputStream in) {
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
StringBuilder sb = new StringBuilder();
String line;
try {
while ((line = reader.readLine())!=null){
sb.append(line).append('\n');
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return sb.toString();
}
}
ActivityMain.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.tushar.jsonparsing.MainActivity">
<ListView
android:id="@+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>
ListItem.xml
If You Are Not Know About List View Check Out Our List View Tut For Android
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:text="TextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/name"
android:paddingTop="6dp"
android:paddingBottom="2dp"
android:textColor="@color/colorPrimaryDark"
android:textSize="16sp"
android:textStyle="bold" />
</LinearLayout>
MainActivity.java
As we are getting the JSON by making HTTP call, I am adding a Async class GetContacts to make http calls on background thread. Add the following method in your main activity class.
package com.tushar.jsonparsing;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
public class MainActivity extends AppCompatActivity {
private String TAG = MainActivity.class.getSimpleName();
private ProgressDialog progressDialog;
private ListView lv;
private static String url = "http://api.myjson.com/bins/sh0id";
ArrayList<HashMap<String,String>> cityList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cityList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
new GetCities().execute();
}
private class GetCities extends AsyncTask<Void,Void,Void>{
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
progressDialog = new ProgressDialog(MainActivity.this);
progressDialog.setMessage("Connecting To Server...");
progressDialog.setCancelable(false);
progressDialog.show();
}
@Override
protected Void doInBackground(Void... params) {
HttpHandler sh = new HttpHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url);
Log.e(TAG, "Response from url: " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
JSONArray cities = jsonObj.getJSONArray("cities");
// looping through All Contacts
for (int i = 0; i < cities.length(); i++) {
JSONObject c = cities.getJSONObject(i);
String name = c.getString("name");
// tmp hash map for single contact
HashMap<String, String> contact = new HashMap<>();
// adding each child node to HashMap key => value
contact.put("name", name);
// adding contact to contact list
cityList.add(contact);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(),
Toast.LENGTH_LONG)
.show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG)
.show();
}
});
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (progressDialog.isShowing())
progressDialog.dismiss();
/** * Updating parsed JSON data into ListView * */
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, cityList,
R.layout.list_item, new String[]{"name"}, new int[]{R.id.name});
lv.setAdapter(adapter);
}
}
}
Run Your App Using Emulator
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