ListView lv = getListView();
ItemAdapter adapter = (ItemAdapter)lv.getAdapter();
if (adapter == null) return;

for (Item q : mSelectedItems) {
    int position = adapter.getItemPosition(q);
    if (position == -1) continue;

    View itemView = lv.getChildAt(position);
    if (itemView == null) continue;

    itemView.setBackgroundColor(getResources().getColor(R.color.orange));
}

public View getView(int position, View convertView, ViewGroup parent) {
...
RelativeLayout itemLayout =
        (RelativeLayout) LayoutInflater.from(mContext).inflate(R.layout.my_layout, parent,
        false);
    if (((MyActivity) mContext).isItemSelected(item)) {
             itemLayout.setBackgroundColor(mContext.getResources().getColor(R.color.orange));
        }
    }