How to send OTP in Android app using Textlocal API ?

Hey guys...

In this blog, we are going to see how to send OTP in Andriod app. We will make an app where we will input the mobile number the OTP will come to that mobile number.

How to send OTP in Android App?

We will send OTP via the TextLocal API. For this, we need the API of TextLocal. 

Steps to get API from TextLocal.

Go and register with TextLocal. Then you will get 10 credits free to test the SMS service.

Then go to the Setting section under setting click create a new API key and after crating copy that API and do the coding.

If you need more Credits!!

If you want more credits then you need to buy with some price. Then there are some procedures to create sender name for your particular business name showing over the sender name, the support team will guide you.

If you have brought the credits then you have to create templates to send OTP or any messages. After requesting the template the team will approve it. If won't unable to create a template then contact to the support team they will guide you. 

After creating the template you have to copy that same template in the coding part.

What we will build?

Enter OTP

Verify OTP

Steps to create this !!!

Step 1.  Create a Project and Add The Internet Permissions

Add the internet permission to our project in AndroidManifest.xml file.

Step 2.  Create The XML file or Design

I have taken one root LinearLayout and two child LineaeLayouts. You can create the design as your need.

Code: activity_main.xml

	<?xml version="1.0" encoding="utf-8"?>
	<LinearLayout
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:orientation="vertical"
	android:padding="20dp"
	>
	<LinearLayout
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:orientation="vertical"
	android:gravity="center"
	android:padding="20dp"
	>
	<TextView
	android:id="@+id/textView"
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:text="Enter your mobile number."
	android:textSize="25sp"
	android:textStyle="bold"
	android:textAlignment="center"
	/>
	<EditText
	android:id="@+id/enterPhone"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:layout_marginStart="8dp"
	android:layout_marginEnd="8dp"
	android:layout_marginBottom="8dp"
	android:ems="10"
	android:inputType="phone"
	android:layout_marginTop="20dp"
	android:hint="Enter mobile number"
	android:padding="15dp"
	/>
	<Button
	android:id="@+id/sendOtp"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:layout_marginTop="20dp"
	android:padding="20dp"
	android:text="Send OTP" />
	</LinearLayout>
	<LinearLayout
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:orientation="vertical"
	android:gravity="center"
	android:padding="20dp"
	android:id="@+id/verify_section"
	android:layout_marginTop="20dp"
	>
	<TextView
	android:id="@+id/textView1"
	android:layout_width="wrap_content"
	android:layout_height="wrap_content"
	android:text="Verify the Otp!!"
	android:textSize="25sp"
	android:textAlignment="center"
	android:textStyle="bold"
	/>
	<EditText
	android:id="@+id/enterOtp"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:layout_marginStart="8dp"
	android:layout_marginEnd="8dp"
	android:layout_marginBottom="8dp"
	android:ems="10"
	android:padding="15dp"
	android:layout_marginTop="20dp"
	android:inputType="number"
	android:hint="Enter otp here"
	/>
	<Button
	android:id="@+id/verifyOtp"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:text="Verify Otp"
	android:padding="20dp"
	android:layout_marginTop="20dp"
	/>
	</LinearLayout>
	<TextView
	android:layout_width="match_parent"
	android:id="@+id/show_result"
	android:layout_height="wrap_content"
	android:textStyle="bold"
	android:textSize="20sp"
	android:textColor="#CA0D0D"
	android:textAlignment="center"
	/>
	</LinearLayout>

view raw activity_main.xml hosted with ❤ by GitHub

Step 3.  Create The Functionality in JAVA

I have mentioned the comments in each line of code please follow the comments to understand, if you are getting any problems, comment on the page below.

Code: MainActivity.java

	package com.example.sendotp;
	import androidx.appcompat.app.AppCompatActivity;
	import android.app.ProgressDialog;
	import android.content.Intent;
	import android.os.Bundle;
	import android.os.StrictMode;
	import android.view.View;
	import android.widget.Button;
	import android.widget.EditText;
	import android.widget.ImageView;
	import android.widget.LinearLayout;
	import android.widget.TextView;
	import android.widget.Toast;
	import java.io.BufferedReader;
	import java.io.InputStreamReader;
	import java.net.URL;
	import java.net.URLConnection;
	import java.util.Random;
	public class MainActivity extends AppCompatActivity {
	// Button used to send otp
	Button send_otp_btn;
	// Button to verify the otp
	Button verify_otp_btn;
	// This is used to store the randow no or otp that will be sent to the user
	int randomNumber;
	// These two are our editexts
	EditText enter_mobile_no_ediText;
	EditText enter_otp_editText;
	// phone_no used to store the phone no from edittext
	String phone_no;
	// get_otp_from_editText used to store the entered otp from verify section
	String get_otp_from_editText;
	// This will sent to the user, the random no
	String random_no_we_sent;
	// This textview used to show the output
	TextView show_result;
	// This layout holds the verify section used to set visible and invisible property
	LinearLayout verify_section;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.activity_main);
	// Used to prevent the Os.NetworkThreadException
	StrictMode.ThreadPolicy policy= new StrictMode.ThreadPolicy.Builder().permitAll().build();
	StrictMode.setThreadPolicy(policy);
	// Link with our edittext enter mobile no
	enter_mobile_no_ediText = findViewById(R.id.enterPhone);
	// button used to submit the phone no
	send_otp_btn = findViewById(R.id.sendOtp);
	// Link with our edittext enter otp to verify
	enter_otp_editText = findViewById(R.id.enterOtp);
	// button used to submit the otp
	verify_otp_btn = findViewById(R.id.verifyOtp);
	// Text View used to show the output
	show_result= findViewById(R.id.show_result);
	// The otp verify page
	verify_section = findViewById(R.id.verify_section);
	// Initially we set to invisible after getting the otp we will again set visible
	verify_section.setVisibility(View.INVISIBLE);
	// Here we set the listener to the send otp button
	send_otp_btn.setOnClickListener(new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	//Here we declared a method to do the send otp stuffs to make the code simpler
	// Below we have initialised this method
	getOtp();
	}
	});
	// Here we set the listener to the verify otp button
	verify_otp_btn.setOnClickListener(new View.OnClickListener() {
	@Override
	public void onClick(View v) {
	//Here we declared a method to verify the otp stuffs to make the code simpler
	// Below we have initialised this method
	verifyOTP();
	}
	});
	}
	private void getOtp() {
	try {
	// Get the data from the mobile no textfield
	phone_no = enter_mobile_no_ediText.getText().toString();
	// To show our mobile no is coming or not
	Toast.makeText(this, phone_no, Toast.LENGTH_SHORT).show();
	// SET THE API FROM THE TEXTLOCAL
	String apiKey = "apikey=" + "YOUR API";
	// GENERATE THE RANDOM NUMBER TO SEND THE OTP
	Random random= new Random();
	randomNumber=random.nextInt(999999);
	// ENTER THE MESSAGE AND SET THE CONCATENATE THE RANDOM VARIABLE
	// IF YOU HAVE CREATED A TEMPLATE THEN PASTE THE CORRECT TEMPLATE
	String message = "Hey, thanks for trying SMART WORK, your OTP is "+randomNumber;
	// ENTER YOUR SENDER NAME
	// IF YOU DONT HAVE THE SENDER NAME DEFAULT IS TXTLCL
	String sender = "&sender=" + "TXTLCL";
	// HERE WE ARE ATTACHING THE MOBILE NO THAT IS COMING FROM THE EDITTEXT
	String numbers = "&numbers=" +phone_no;
	// HERE WE ARE MAKING THE REQUEST TO THE URL
	// WE HAVE ATTACHED THE PROPER USL WITH API KEY, SENDER NAME, NUMBER AND MESSAGE FROM THE ABOVE VARIABLE
	String data = "https://api.textlocal.in/send/?apikey="+apiKey+"1&sender="+sender+"&numbers="+numbers+"&message="+message;
	URL url = new URL(data);
	URLConnection conn = url.openConnection();
	conn.setDoOutput(true);
	// Get the response
	BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
	String line;
	String sResult="";
	while ((line = rd.readLine()) != null) {
	// Process line...
	sResult=sResult+line+" ";
	}
	rd.close();
	// STORING THE RANDOM NO TO NEXT VERIFY
	random_no_we_sent = String.valueOf(randomNumber);
	// SHOWING TOAST THAT IS Otp Sent Successfully"
	Toast.makeText(this, "Otp Sent Successfully", Toast.LENGTH_SHORT).show();
	// AFTER SENDING THE OTP
	verify_section.setVisibility(View.VISIBLE);
	} catch (Exception e) {
	// HERE WE SHOWN THE ERROR
	System.out.println("Error SMS "+e);
	Toast.makeText(this,"Error "+ e.toString(), Toast.LENGTH_SHORT).show();
	}
	}
	// HERE WE HAVE VERIFIED THE OTP
	private void verifyOTP() {
	// GET THE OTP FROM THE TEXTFIELD
	get_otp_from_editText = enter_otp_editText.getText().toString();
	// THEN CHECK THE RANDOM NUMBER WITH OTP FROM EDITTEXT
	if(random_no_we_sent.equals(get_otp_from_editText)) {
	show_result.setText("Otp is verified.");
	} else {
	// SHOW THE OUTPUT
	show_result.setText("NOT VERIFIED");
	}
	}
	}

view raw MainActivity.java hosted with ❤ by GitHub

Now its time to make the close of this blog thank you for reading this blog, if you are getting any problem comment us.
THANK YOU.

Also, read..below blogs

1. What is API and How to learn it? 

2. Fetch JSON data from REST API in Android?