How to pass an arrayList to another activity using intents in Android Kotlin?

This example demonstrates how to pass an arrayList to another activity using intents in Android 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:id="@+id/relativeLayout"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".MainActivity">    <TextView       android:id="@+id/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="@color/colorPrimaryDark"       android:textSize="48sp"       android:textStyle="bold" />    <TextView       android:layout_width="wrap_content"       android:layout_height="wrap_content"       android:layout_below="@id/textView"       android:layout_centerHorizontal="true"       android:layout_marginTop="50dp"       android:padding="8dp"       android:text="Passing an arrayList to another activity using intents"       android:textAlignment="center"       android:textColor="@android:color/holo_red_dark"       android:textSize="24sp"       android:textStyle="bold" />    <Button       android:id="@+id/button"       android:layout_width="wrap_content"       android:layout_height="wrap_content"       android:layout_centerInParent="true"       android:background="@android:color/holo_red_dark"       android:padding="4dp"       android:text="Pass array to 2nd Activity"       android:textColor="@android:color/background_light"       android:textStyle="bold" /> </RelativeLayout>

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

Example

import android.content.Intent import android.os.Bundle import android.widget.Button import androidx.appcompat.app.AppCompatActivity class MainActivity : AppCompatActivity() {    lateinit var button: Button    var numbers: ArrayList<String> = ArrayList()    override fun onCreate(savedInstanceState: Bundle?) {       super.onCreate(savedInstanceState)       setContentView(R.layout.activity_main)       title = "KotlinApp"       button = findViewById(R.id.button)       button.setOnClickListener {          numbers.add("ONE")          numbers.add("TWO")          numbers.add("THREE")          numbers.add("FOUR")          numbers.add("FIVE")          val intent = Intent(this@MainActivity, SecondActivity::class.java)          intent.putExtra("key", numbers)          startActivity(intent)       }    } }

Step 4 − Create a new Activity and add the following code −

Example

SecondActivity.kt

import androidx.appcompat.app . AppCompatActivity import android.os . Bundle import android.widget . TextView class SecondActivity : AppCompatActivity() {    private lateinit var textView : TextView    override fun onCreate ( savedInstanceState : Bundle ?) {       super .onCreate( savedInstanceState )       setContentView( R . layout . activity_second )       textView = findViewById( R . id . textView )       val numberList = intent .getSerializableExtra( "key" )       textView . text = numberList .toString()    } }

activity_second.xml

<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 =".SecondActivity" >    <TextView       android :layout_width ="wrap_content"       android :layout_height ="wrap_content"       android :layout_centerHorizonta l ="true"       android :layout_marginTop ="90dp"       android :padding ="8dp"       android :text ="Second Activity"       android :textAlignment ="center"       android :textColor ="@android:color/holo_red_dark"       android :textSize ="24sp"       android :textStyle ="bold" />    <TextView       android :id ="@+id/textView"       android :layout_width ="wrap_content"       android :layout_height ="wrap_content"       android :layout_centerInParent ="true"       android :textColor ="@android:color/background_dark"       android :textSize ="24sp"       android :textStyle ="bold" /> </RelativeLayout>

Step 5 − 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