How to display a list view in an Android Alert Dialog in Kotlin?

Kotlin Apps/Applications Mobile Development

This example demonstrates how to display a list view in an Android Alert Dialog.

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.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="8dp">
   <TextView
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_marginTop="40dp"
      android:text="Tutorials Point"
      android:textAlignment="center"
      android:textColor="@android:color/holo_blue_light"
      android:textSize="32sp"
      android:textStyle="bold" />
   <Button
      android:id="@+id/btnClick"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:onClick="openDialog"
      android:text="Click here to get ListView in Alert Dialog"
      android:textSize="12sp"
      android:textStyle="bold" />
</RelativeLayout>

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

import android.os.Bundle
import android.view.View
import android.widget.ArrayAdapter
import android.widget.ListView
import android.widget.Toast
import androidx.appcompat.app.AlertDialog
import androidx.appcompat.app.AppCompatActivity
class MainActivity : AppCompatActivity() {
   var country = arrayOf(
      "India", "Brazil", "Argentina",
      "Portugal", "France", "England", "Italy"
   )
   lateinit var adapter: ArrayAdapter<String>
   lateinit var listView: ListView
   lateinit var alertDialog: AlertDialog.Builder
   lateinit var dialog: AlertDialog
   override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      title = "KotlinApp"
   }
   fun openDialog(view: View) {
      alertDialog = AlertDialog.Builder(this)
      val rowList: View = layoutInflater.inflate(R.layout.row, null)
      listView = rowList.findViewById(R.id.listView)
      adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, country)
      listView.adapter = adapter
      adapter.notifyDataSetChanged()
      alertDialog.setView(rowList)
      dialog = alertDialog.create()
      dialog.show()
   }
   fun closeDialog(view: View) {
      dialog.dismiss()
      Toast.makeText(baseContext, "Dialog Closed", Toast.LENGTH_SHORT).show()
   }
}

Step 4 − Add the following code to androidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="app.com.kotlipapp">
   <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 −