how does arraylist add work code example

Example 1: java arraylist add

//create ArrayList
ArrayList<String> arrayList = new ArrayList<String>();
//add item to ArrayList
arrayList.add("item");
//check if ArrayList contains item (returns boolean)
System.out.println(arrayList.contains("item"));
//remove item from ArrayList
arrayList.remove("item");

Example 2: Java arraylist if you don't want to use add()

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        ListView myListView = (ListView) findViewById(R.id.myListView);

        final ArrayList<String> myFriendsList = new ArrayList<String>(asList("Friend1", "Friend2", "Friend3", "Friend4", "Friend5"));

        // set the layout of the list
        ArrayAdapter<String> friendsArrayAdapter = new ArrayAdapter<String>(this,
                                                android.R.layout.simple_list_item_1, myFriendsList);

        // connect adapter to myFriendsList
        myListView.setAdapter(friendsArrayAdapter);

        // set onClickListener
        myListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

                Toast.makeText(MainActivity.this, myFriendsList.get(position), Toast.LENGTH_SHORT).show();
            }
        });




    }
}