Modification of ListviewAdapter

I have found a code for a listview with images on this page: http://cursoandroidstudio.blogspot.com.es/2014/07/listview-con-imagenes.html I need it to work with bitmap type, I have changed everything of the type int[] to Bitmap[] . The result is as follows:

public class MainActivity extends AppCompatActivity {

ListViewAdapter adapter;

String[] titulo = new String[]{
        "titulo1",
        "titulo2",
        "titulo3",
        "titulo4",
};

Bitmap[] imagenes = {
        BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher),
        BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher),
        BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher),
        BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher)
};

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

    final ListView lista = (ListView) findViewById(R.id.listView1);
    adapter = new ListViewAdapter(this, titulo, imagenes);
    lista.setAdapter(adapter);

    }
}



public class ListViewAdapter extends BaseAdapter {
// Declare Variables
Context context;
String[] titulos;
Bitmap[] imagenes;
LayoutInflater inflater;

public ListViewAdapter(Context context, String[] titulos, Bitmap[] imagenes) {
    this.context = context;
    this.titulos = titulos;
    this.imagenes = imagenes;
}

@Override
public int getCount() {
    return titulos.length;
}

@Override
public Object getItem(int position) {
    return null;
}

@Override
public long getItemId(int position) {
    return 0;
}

public View getView(int position, View convertView, ViewGroup parent) {

    // Declare Variables
    TextView txtTitle;
    ImageView imgImg;

    //http://developer.android.com/intl/es/reference/android/view/LayoutInflater.html
    inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View itemView = inflater.inflate(R.layout.list_row, parent, false);

    // Locate the TextViews in listview_item.xml
    txtTitle = (TextView) itemView.findViewById(R.id.list_row_title);
    imgImg = (ImageView) itemView.findViewById(R.id.list_row_image);

    // Capture position and set to the TextViews
    txtTitle.setText(titulos[position]);
    imgImg.setImageBitmap(imagenes[position]);

        return itemView;
    }
}

But it doesn't work for me, does anyone know why or how I can fix it?