Dynamically add elements in ListView in android?

This example demonstrates how do I dynamically add elements in ListView in android.
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.
<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" >

   <Button
      android:id="@+id/button1"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:layout_below="@+id/editText1"
      android:layout_centerHorizontal="true"
      android:text="Add Values to listView" />

   <EditText
      android:id="@+id/editText1"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_alignParentTop="true"
      android:layout_centerHorizontal="true"
      android:layout_marginTop="26dp"
      android:ems="10"
      android:hint="Add elements listView" />

   <ListView
      android:id="@+id/listView1"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_below="@+id/button1"
      android:layout_centerHorizontal="true" >
   </ListView>
</RelativeLayout>
Step 3 − Add the following code to src/MainActivity.java
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;

public class MainActivity extends Activity {

   ListView listview;
   Button addButton;
   EditText GetValue;
   String[] ListElements = new String[] {
      "Android",
      "PHP",
      "Python",
   };
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);

      listview = findViewById(R.id.listView1);
      addButton = findViewById(R.id.button1);
      GetValue = findViewById(R.id.editText1);

      final List<String> ListElementsArrayList = new ArrayList<>(Arrays.asList(ListElements));
      final ArrayAdapter<String> adapter = new ArrayAdapter<>
      (MainActivity.this, android.R.layout.simple_list_item_1, ListElementsArrayList);
      listview.setAdapter(adapter);

      addButton.setOnClickListener(new View.OnClickListener() {
         @Override
         public void onClick(View v) {
            ListElementsArrayList.add(GetValue.getText().toString());
            adapter.notifyDataSetChanged();
         }
      });
   }
}
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.sample">

   <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 Run  Icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –