Problem with android single choice dialog using arrayAdapter

I tried to do a custom single choice dialog using an ArrayAdapter. First i created a Array Adapter with anonymous class.

private final Dialog createListFile(final String[] fileList) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle(R.string.compare);
ArrayAdapter<String> dialogArrayAdapter = new ArrayAdapter<String>(this, R.layout.dialog_row, fileList) {

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolderDialog holder = null;
            if (convertView == null) {are
                LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                convertView = inflater.inflate(R.layout.dialog_row, null);
                holder = new ViewHolderDialog();
                holder.date = (TextView) convertView.findViewById(R.id.dialogDate);
                holder.days = (TextView) convertView.findViewById(R.id.dialogDays);
                convertView.setTag(holder);
            } else {
                holder = (ViewHolderDialog) convertView.getTag();
            }
     开发者_高级运维       String item = getItem(position);
            holder.date.setText(item);
            holder.days.setText("giorni");
            return convertView;
        }
    };

Then i called the setSingleChoiceItems method of the builder to create a list of items with a check mark displayed; passing as the first parameter arrayAdapter created earlier.

builder.setSingleChoiceItems(dialogArrayAdapter, -1, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
    n = whichButton;
        }
    });

The problem is that when I run the code shows the check mark. Where am I doing wrong?

builder.setSingleChoiceItems adds radio group check marks automatically. If you do not need this, then use builder.setItems. See: http://developer.android.com/guide/topics/ui/dialogs.html

Look at the code and android developer and. Using builder.setItems do you will improve the performance when not use a ArrayAdapter.