ContactsAdapter.java

public class ContactsAdapter extends BaseAdapter {

    private final ArrayList list;
    private int selectedItem = -1; // no item selected by default

    // put neccessary code here - it's not important in this description

    public ContactsAdapter(List<Contact> contacts) {
        list = new ArrayList();
        list.addAll(contacts);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final View result;

        if (convertView == null) {
            result = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_contact, parent, false);
        } else {
            result = convertView;
        }

        highlightItem(position, result);

        Contact contact = getItem(position);
        ((TextView) result.findViewById(android.R.id.text1)).setText(contact.name);
        return result;
    }

    /**
     * methods from StringUtils calls:
     * getContext().getResources().getColor(int resourceId)
     * getContext().getResources().getDrawable(int resourceId)
     * You can use them in your own context 
     * (e.g. generic application context or you can pass activity context)
     */
    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    private void highlightItem(int position, View result) {
        if(position == selectedItem) {
            // you can define your own color of selected item here
            result.setBackgroundColor(StringUtils.getColorFromResources(R.color.light_blue));
        } else {
            // you can define your own default selector here
            result.setBackground(StringUtils.getDrawableFromResources(R.drawable.abs__list_selector_holo_light));
        }
    }
    
    public void setSelectedItem(int selectedItem) {
        this.selectedItem = selectedItem;
    }

    // put rest of your necessary code here...

}