Android Programming Tutorial 41 : RESTfull WebServices Using JSON In Android

RestFull Web Services:

If we want to store, retrieve the data from the remote data base we have to take the help of the web services.To work with the web services we need HTTP Networking Calls to interacting the remote database.

It is easy to communicate with a web service from an Android application. All you need is a active web service, its WSDL url, web method name, web service name space.

Here we are seeing the RestFull Web services Example tutorial.

Android apps need data, and many use RESTful services (at their heart, simple HTTP networking calls) to get and send data over the web. In this tutorial we develope how to integrate Android apps with Remote networks, and use RESTful web requests to access data from them. The course concentrates on the different ways of making requests with the built-in classes in the Android SDK, but also provides an overview of popular open-source networking libraries, David Gassner will describe how to retrieve content with simple GET and POST requests, parse the responses, and pass user credentials to services that support HTTP basic authentication. He'll also show you how to send parameters with your requests and format POST requests with JSON.

OutPut Of the Tutorial:

Create Android Application:

• File >> New >> Android Application
• Enter Project name: RestFullWebServicesApp
• Package: com.ambilpursunil.newapp
• Keep other default selections, click Next until you reach Finish

                               

 1.Simply Copy and Past the Code which is display below in the  MainActivity.java 

package com.ambilpursunil.newapp;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

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 org.json.JSONArray;

import android.app.Activity;

import android.os.Bundle;

import android.os.StrictMode;

import android.widget.TextView;

public class MainActivity1 extends Activity {

            @Override

            protected void onCreate(Bundle savedInstanceState) {

                        super.onCreate(savedInstanceState);

  StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()

                        .permitAll().build();

                        StrictMode.setThreadPolicy(policy);

                        setContentView(R.layout.main);

                      //HTTP  Networking Calls

                        HttpClient httpClient = new DefaultHttpClient();

HttpPost httpPost = new HttpPost(

 "http://www.cheesejedi.com/rest_services/get_big_cheese.php?puzzle=1");

                       TextView tv = (TextView) findViewById(R.id.textView1);

                       try {

    HttpResponse httpResponse = httpClient.execute(httpPost);

                    String jsonResult = inputStreamtoString(

                                                                                                                                               httpResponse.getEntity().getContent()).toString();

                   //JSONArray Calls  

            JSONArray jsonArray = new JSONArray(jsonResult);

                for (int i = 0; i < jsonArray.length(); i++) {

 tv.append("id: " +jsonArray.getJSONObject(i).getString("id").toString()+ "\n");

 tv.append("level: " + jsonArray.getJSONObject(i).getString("level")

                .toString() +"\n");

tv.append("time_in_secs: " + jsonArray.getJSONObject(i).getString("time_in_secs")

                .toString() + "\n");

tv.append("par: " + jsonArray.getJSONObject(i).getString("par")

                .toString() + "\n");

tv.append("quote: " + jsonArray.getJSONObject(i).getString("quote")

                 .toString() + " \n");

tv.append("time_stamp: " + jsonArray.getJSONObject(i).getString("time_stamp")

                  .toString() + "\n\n");

                  }

                   } catch (Exception e) {

                   e.getLocalizedMessage();

                  }

             }

             private StringBuilder inputStreamtoString(InputStream is) {

                  String line = "";

                  StringBuilder sb = new StringBuilder();

                  InputStreamReader usr = new InputStreamReader(is);

                  BufferedReader br = new BufferedReader(usr);

                  try {

                  while ((line = br.readLine()) != null) {

                  sb.append(line);

                  }

                  } catch (IOException e) {

                  e.printStackTrace();

                  }

                  return sb;

            }

 }

 2.Simple Copy and Past the below code:  actvitiy_main.xml

<ScrollView 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"

    android:id="@+id/scrollview">

   

    <LinearLayout

        android:layout_width="match_parent"

            android:layout_height="wrap_content" >

    <TextView

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:id="@+id/textView1"

        android:textAppearance="?android:attr/textAppearanceLarge" />

   

    </LinearLayout>

</ScrollView>

3.Copy and past the code for manifest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.ambilpursunil.newapp"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="18"

        android:targetSdkVersion="18" />

    <uses-permission android:name="android.permission.INTERNET" />

    <application

        android:allowBackup="true"

        android:icon="@drawable/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" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

            </application>

</manifest>

4.Right click on the project and Run As-->Android Application

OutPut Of the Tutorial:

OutPut:

When our application launch data will be visible on the screen.

Please Send Your Comments To ambilpura.sunil@gmail.com

Stay Tune For Next Tutorial... WebServices Using GET Method In Android: