ThemedSpinnerAdapter.Helper

 public class MyAdapter extends BaseAdapter implements ThemedSpinnerAdapter {
     private final ThemedSpinnerAdapter.Helper mDropDownHelper;

     public CheeseAdapter(Context context) {
         mDropDownHelper = new ThemedSpinnerAdapter.Helper(context);
         // ...
     }

     @Override
     public View getDropDownView(int position, View convertView, ViewGroup parent) {
         View view;

         if (convertView == null) {
             // Inflate the drop down using the helper's LayoutInflater
             LayoutInflater inflater = mDropDownHelper.getDropDownViewInflater();
             view = inflater.inflate(R.layout.my_dropdown, parent, false);
         }

         // ...
     }

     @Override
     public void setDropDownViewTheme(@Nullable Resources.Theme theme) {
         // Pass the new theme to the helper
         mDropDownHelper.setDropDownViewTheme(theme);
     }

     @Override
     public Resources.Theme getDropDownViewTheme() {
         // Return the helper's value
         return mDropDownHelper.getDropDownViewTheme();
     }
 }