How to create Spinner-list using CustomAdapter in android

Change your adapter like this

public class CustomAdapter extends ArrayAdapter<RowItem> {

    LayoutInflater flater;

    public CustomAdapter(Activity context, int resouceId, int textviewId, List<RowItem> list){

        super(context,resouceId,textviewId, list);
//        flater = context.getLayoutInflater();
    }

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

        return rowview(convertView,position);
    }

    @Override
    public View getDropDownView(int position, View convertView, ViewGroup parent) {
        return rowview(convertView,position);
    }

    private View rowview(View convertView , int position){

        RowItem rowItem = getItem(position);

        viewHolder holder ;
        View rowview = convertView;
        if (rowview==null) {

            holder = new viewHolder();
            flater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            rowview = flater.inflate(R.layout.listitems_layout, null, false);

            holder.txtTitle = (TextView) rowview.findViewById(R.id.title);
            holder.imageView = (ImageView) rowview.findViewById(R.id.icon);
            rowview.setTag(holder);
        }else{
            holder = (viewHolder) rowview.getTag();
        }
        holder.imageView.setImageResource(rowItem.getImageId());
        holder.txtTitle.setText(rowItem.getTitle());

        return rowview;
    }

    private class viewHolder{
        TextView txtTitle;
        ImageView imageView;
    }
}