To dynammically add new elements into listview we need a Edittext(etAddItem) to input the item/element, a Button(btnAdd) for adding item to the list, and a listview which shows elements in a vertical scrolling manner.
finally, adapter works as a communication channel between Listview and ArrayList.
arrayList = new ArrayList();
adapter = new ArrayAdapter(getApplicationContext(), android.R.layout.simple_spinner_item, arrayList);
// Here, you set the data in your ListView