Example Tutorial Retrofit 2.0 Method GET Using Parameter

Hello everyone, today i going to share a nice tutorial about how to use method GET of Retrofit 2.0. I will get my profile by parameter.

Example :

My profile's ID is 1. So the url become www.url.com/endpoint?paremeter=1

In this example i just use one data profile with ID = 1. You can improve your project by creating much profile.

As you can see at the video above, after success get data profile, the response will display all attribute of my profile like ID, NAME, JOB and AGE

PREPARATION

First, in order we to able to use Retrofit 2.0, we have you compile the following libraries in your dependencies build.gradle (Module: app) :

// retrofit 2.0
compile 'com.squareup.retrofit2:retrofit:2.0.2'
compile 'com.squareup.retrofit2:converter-gson:2.0.2'

Add uses-permission in your AndroidManifest.xml like the following permission :

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

IMPLEMENTATION

First, create an interface that define Method GET of Retrofit that we'll use to get data profile. Give it name as ApiService.java. Paste the following code :

	package com.example.putuguna.retrofit2.apis;
	import com.example.putuguna.retrofit2.models.Profile;
	import retrofit2.Call;
	import retrofit2.http.GET;
	import retrofit2.http.Query;
	/**
	* Created by putuguna on 14/06/16.
	*/
	public interface ApiService {
	@GET("myself")
	Call<Profile> getMyProfile(@Query("id") String id);
	}

view raw ApiService.java hosted with ❤ by GitHub

On code above, "myself" is the endpoint. Endpoint is a attribute after url (ww.url.com/endpoint). @Query("id") used to define the parameter


Second, create new java class, give it name as LoggingInterceptor.java. Paste the following code :

	package com.example.putuguna.retrofit2.apis;
	import android.util.Log;
	import java.io.IOException;
	import okhttp3.Interceptor;
	import okhttp3.Request;
	import okhttp3.Response;
	import okhttp3.ResponseBody;
	import okio.Buffer;
	/**
	* Created by putuguna on 1/27/2016.
	*/
	public class LoggingInterceptor implements Interceptor {
	@Override
	public Response intercept(Chain chain) throws IOException {
	Request request = chain.request();
	long t1 = System.nanoTime();
	String requestLog = String.format("Sending request %s on %s%n%s",
	request.url(), chain.connection(), request.headers());
	//YLog.d(String.format("Sending request %s on %s%n%s",
	// request.url(), chain.connection(), request.headers()));
	if (request.method().compareToIgnoreCase("post") == 0) {
	requestLog = "\n" + requestLog + "\n" + bodyToString(request);
	}
	Log.d("TAG", "request" + "\n" + requestLog);
	Response response = chain.proceed(request);
	long t2 = System.nanoTime();
	String responseLog = String.format("Received response for %s in %.1fms%n%s",
	response.request().url(), (t2 - t1) / 1e6d, response.headers());
	String bodyString = response.body().string();
	Log.d("TAG", "response" + "\n" + responseLog + "\n" + bodyString);
	return response.newBuilder()
	.body(ResponseBody.create(response.body().contentType(), bodyString))
	.build();
	}
	public static String bodyToString(final Request request) {
	try {
	final Request copy = request.newBuilder().build();
	final Buffer buffer = new Buffer();
	copy.body().writeTo(buffer);
	return buffer.readUtf8();
	} catch (final IOException e) {
	return "did not work";
	}
	}
	}

view raw LoggingInterceptor.java hosted with ❤ by GitHub

This java class help us to set the output of process get data profile. You can see the output on the android studio logcat.


Third, create new java class, give it name as ApiClient.java, in this class we define the URL, set the LoggingInterceptor and client. Paste the following code :


Forth, create new java class, give it name as ProfileModel.java. This class will used to store the response of the JSON. Paste the following code :

	package com.example.putuguna.retrofit2.models;
	import com.google.gson.annotations.SerializedName;
	/**
	* Created by putuguna on 14/06/16.
	*/
	public class Profile {
	@SerializedName("id")
	private String id;
	@SerializedName("name")
	private String name;
	@SerializedName("job")
	private String job;
	@SerializedName("age")
	private String age;
	public Profile(String id, String name, String job, String age) {
	this.id = id;
	this.name = name;
	this.job = job;
	this.age = age;
	}
	public Profile() {
	}
	public String getId() {
	return id;
	}
	public void setId(String id) {
	this.id = id;
	}
	public String getName() {
	return name;
	}
	public void setName(String name) {
	this.name = name;
	}
	public String getJob() {
	return job;
	}
	public void setJob(String job) {
	this.job = job;
	}
	public String getAge() {
	return age;
	}
	public void setAge(String age) {
	this.age = age;
	}
	}

view raw ProfileModel.java hosted with ❤ by GitHub

The attribute of @SerializedName("...") must same as the attribute in the JSON. Example in the JSON write as "id", the serializedName become to @SerializedName("id")


Last, create layout and java class of MainActivity.

activity_main.xml, paste the following code :

	<?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: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.example.putuguna.retrofit2.MainActivity">
	<TextView
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:gravity="center"
	android:id="@+id/hello"
	android:text="Hello there, i trying to get my profile using Retrofit 2" />
	<Button
	android:layout_below="@+id/hello"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:id="@+id/getprofile"
	android:text="Get Profile"/>
	<LinearLayout
	android:gravity="center"
	android:layout_marginTop="20dp"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:layout_below="@+id/getprofile"
	android:orientation="vertical">
	<TextView
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:id="@+id/idprofile"/>
	<TextView
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:id="@+id/nameprofle"/>
	<TextView
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:id="@+id/jobprofile"/>
	<TextView
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:id="@+id/ageprofle"/>
	</LinearLayout>
	</RelativeLayout>

view raw activity_main.xml hosted with ❤ by GitHub

MainActivity.java, paste the following code :

	package com.example.putuguna.retrofit2;
	import android.app.ProgressDialog;
	import android.support.v7.app.AppCompatActivity;
	import android.os.Bundle;
	import android.view.View;
	import android.widget.Button;
	import android.widget.TextView;
	import android.widget.Toast;
	import com.example.putuguna.retrofit2.apis.ApiClient;
	import com.example.putuguna.retrofit2.apis.ApiService;
	import com.example.putuguna.retrofit2.models.Profile;
	import retrofit2.Call;
	import retrofit2.Callback;
	import retrofit2.Response;
	public class MainActivity extends AppCompatActivity {
	private Button getData;
	private TextView id;
	private TextView name;
	private TextView job;
	private TextView age;
	private ProgressDialog progressDialog;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.activity_main);
	getData = (Button) findViewById(R.id.getprofile);
	id = (TextView) findViewById(R.id.idprofile);
	name = (TextView) findViewById(R.id.nameprofle);
	job = (TextView) findViewById(R.id.jobprofile);
	age = (TextView) findViewById(R.id.ageprofle);
	getData.setOnClickListener(new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	progressDialog = new ProgressDialog(MainActivity.this);
	progressDialog.setTitle("Get My Prole");
	progressDialog.setMessage("Loading ...");
	progressDialog.show();
	getProfile();
	}
	});
	}
	private void getProfile(){
	ApiService apiService = ApiClient.getClient().create(ApiService.class);
	Call<Profile> call = apiService.getMyProfile("1");
	call.enqueue(new Callback<Profile>() {
	@Override
	public void onResponse(Call<Profile> call, Response<Profile> response) {
	progressDialog.dismiss();
	Profile p = response.body();
	id.setText(p.getId());
	name.setText(p.getName());
	job.setText(p.getJob());
	age.setText(p.getAge());
	}
	@Override
	public void onFailure(Call<Profile> call, Throwable t) {
	progressDialog.dismiss();
	Toast.makeText(MainActivity.this, "Failed to load", Toast.LENGTH_LONG).show();
	}
	});
	}
	}

view raw MainActivity.java hosted with ❤ by GitHub

Done! Run your project, and hope it running well.