How to obtain the phone number of the Android phone programmatically using Kotlin?

This example demonstrates how to obtain the phone number of the Android phone programmatically using kotlin.

Step 1 − Create a new project in Android Studio, go to File? New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

Example

<?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"
   tools:context=".MainActivity">
   <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerHorizontal="true"
      android:layout_marginTop="50dp"
      android:padding="8dp"
      android:text="Tutorials Point"
      android:textColor="@android:color/holo_green_dark"
      android:textSize="48sp"
      android:textStyle="bold" />
   <TextView
      android:id="@+id/textView"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:padding="8dp"
      android:textColor="@android:color/holo_blue_dark"
      android:textSize="24sp"
      android:textStyle="bold" />
</RelativeLayout>

Step 3 − Add the following code to src/MainActivity.kt

Example

import android.Manifest
import android.content.Context
import android.content.pm.PackageManager
import android.os.Bundle
import android.telephony.TelephonyManager
import android.widget.TextView
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
class MainActivity : AppCompatActivity() {
   private lateinit var textView: TextView
   private val permission = 101
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
      textView = findViewById(R.id.textView)
      val telephonyManager = getSystemService(Context.TELEPHONY_SERVICE) as
      TelephonyManager
      if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_SMS) !=
      PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this,
      Manifest.permission.READ_PHONE_NUMBERS) != PackageManager.PERMISSION_GRANTED &&
      ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE) !=
      PackageManager.PERMISSION_GRANTED) {
         ActivityCompat.requestPermissions(this, arrayOf(Manifest.permission.READ_PHONE_STATE), permission)
      }
   textView.text = telephonyManager.line1Number
   }
   override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String?>,
   grantResults: IntArray) {
      when (requestCode) {
         permission -> {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
               Toast.makeText(this, "Permission Granted", Toast.LENGTH_SHORT).show()
            } else {
               Toast.makeText(this, "Permission Denied", Toast.LENGTH_SHORT).show()
            }
         }
      }
   }
}

Step 4 − Add the following code to androidManifest.xml

Example

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="app.com.myapplication">
   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      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>
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project's activity files and click the Run icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen