IngredientListActivity.java

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                adapter.getItem(position).setChecked(!adapter.getItem(position).isChecked());
                adapter.notifyDataSetChanged();
                deleteButton.setVisibility(adapter.isAnyItemSelected()? View.VISIBLE : View.INVISIBLE);
            }
        });