AndroidStudio - ListView

public class ListViewActivity extends Activity implements AdapterView.OnItemClickListener

{

private ListView listView;

private AdapterListView adapterListView;

private ArrayList itens;

@Override
public void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    //carrega o layout onde contem o ListView
    setContentView(R.layout.activity_list_view);

    //Pega a referencia do ListView
    listView = (ListView) findViewById(R.id.list);
    //Define o Listener quando alguem clicar no item.
    listView.setOnItemClickListener(this);

    createListView();
}

private void createListView()
{
    //Criamos nossa lista que preenchera o ListView
    itens = new ArrayList<ItemListView>();
    ItemListView item1 = new ItemListView("Biologia", R.drawable.bio);
    ItemListView item2 = new ItemListView("Historia", R.drawable.hist);
    ItemListView item3 = new ItemListView("Matemática", R.drawable.mat);
    ItemListView item4 = new ItemListView("Literatura", R.drawable.lit);

    itens.add(item1);
    itens.add(item2);
    itens.add(item3);
    itens.add(item4);

    //Cria o adapter
    adapterListView = new AdapterListView(this, itens);

    
    listView.setAdapter(adapterListView);
    
    listView.setCacheColorHint(Color.TRANSPARENT);
}

public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3){
    
    ItemListView item = adapterListView.getItem(arg2);
    
    Toast.makeText(this, "Você Clicou em: " + item.getTexto(), Toast.LENGTH_LONG).show();
    
}

switch(position){

case 0:

intent = new Intent(getBaseContext(), Bio.class);

startActivity(intent);

break;

case 1:

intent = new Intent(getBaseContext(), Hist.class);

startActivity(intent);

break;

case 2:

intent = new Intent(getBaseContext(), Mat.class);

startActivity(intent);

break;

case 3:

intent = new Intent(getBaseContext(), Lit.class);

startActivity(intent);

break;

}