Make a Call in an Android Device Using Kotlin

This example demonstrates how to make a call in an Android device 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"
   android:padding="8dp"
   tools:context=".MainActivity">
   <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerHorizontal="true"
      android:layout_marginTop="50dp"
      android:text="Tutorials Point"
      android:textAlignment="center"
      android:textColor="@android:color/holo_green_dark"
      android:textSize="32sp"
      android:textStyle="bold" />
   <EditText
      android:id="@+id/etNumber"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_above="@id/button"
      android:layout_centerInParent="true"
      android:inputType="phone" />
   <Button
      android:id="@+id/button"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:text="Dial"
      android:textColor="@android:color/holo_purple"
      android:textSize="24sp"
      android:textStyle="bold" />
</RelativeLayout>

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

Example

import android.Manifest
import android.content.Intent
import android.content.pm.PackageManager
import android.net.Uri
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
class MainActivity : AppCompatActivity() {
   private lateinit var button: Button
   private lateinit var editText: EditText
   private val requestCall = 1
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
      editText = findViewById(R.id.etNumber)
      button = findViewById(R.id.button)
      button.setOnClickListener {
         makePhoneCall()
      }
   }
   private fun makePhoneCall() {
      val number: String = editText.text.toString()
      if (number.trim { it <= ' ' }.isNotEmpty()) {
         if (ContextCompat.checkSelfPermission(
            this@MainActivity,
            Manifest.permission.CALL_PHONE
         ) != PackageManager.PERMISSION_GRANTED
         ) {
            ActivityCompat.requestPermissions(
               this@MainActivity,
               arrayOf(Manifest.permission.CALL_PHONE),
               requestCall
            )
            } else {
               val dial = "tel:$number"
               startActivity(Intent(Intent.ACTION_CALL, Uri.parse(dial)))
            }
         } else {
            Toast.makeText(this@MainActivity, "Enter Phone Number", Toast.LENGTH_SHORT).show()
         }
      }
      override fun onRequestPermissionsResult(
         requestCode: Int,
         permissions: Array<String?>,
         grantResults: IntArray
      ) {
         if (requestCode == requestCall) {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
               makePhoneCall(
           } 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">
<uses-permission android:name="android.permission.CALL_PHONE" />
   <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