How to get data from realm model class in adapter

Question

I want to add search filter in my activity where data is being displayed in a listview, from a model class which extends RealmObject. But during the addition of filter it throws following exception in adapter class.

java.lang.IllegalStateException: Realm access from incorrect thread. Realm objects can only be accessed on the thread they were created.

I understood the problem but couldn't find any way out to access realm model class data in adapter class? Thanks for you time and help. Here is the adapter class code

@Override
public Filter getFilter()
{
    if(valueFilter == null)
    {
        valueFilter = new ValueFilter();
    }

    return valueFilter;
}    

private class ValueFilter extends Filter {
    @Override
    protected FilterResults performFiltering(CharSequence constraint)
    {
        FilterResults results = new FilterResults();

        if (constraint != null && constraint.length() > 0)
        {
            ArrayList<ShopModel> filterList = new ArrayList<>();
            for (int i = 0; i < copyList.size(); i++)
            {
                    if ((copyList.get(i).getShop_name().toLowerCase())
                            .contains(constraint.toString().toLowerCase()))

Above is line where it throws exception as getShop_name() is method of realm model class

                    {
                        filterList.add(copyList.get(i));
                    }

            }
            results.count = filterList.size();
            results.values = filterList;
        }
        else
        {
            results.count = copyList.size();
            results.values = copyList;
        }
        return results;

    }

    @Override
    protected void publishResults(CharSequence constraint, FilterResults results) {
        arrayList = (ArrayList<ShopModel>) results.values;
        notifyDataSetChanged();
    }

}

Note : this code for adding search filter is working fine when data is accessed from a model class which doesn't extend RealmObject class