Only select only one radio button from listview

Keep the currently checked RadioButton in a variable in your Activity. In the OnClickListener of your RadioButtons do this:

// checks if we already have a checked radiobutton. If we don't, we can assume that 
// the user clicked the current one to check it, so we can remember it.
if(mCurrentlyCheckedRB == null) 
    mCurrentlyCheckedRB = (RadioButton) v;
    mCurrentlyCheckedRB.setChecked(true);
}

// If the user clicks on a RadioButton that we've already stored as being checked, we 
// don't want to do anything.       
if(mCurrentlyCheckedRB == v)
    return;

// Otherwise, uncheck the currently checked RadioButton, check the newly checked 
// RadioButton, and store it for future reference.
mCurrentlyCheckedRB.setChecked(false);
((RadioButton)v).setChecked(true);
mCurrentlyCheckedRB = (RadioButton)v;   

Here's my code:

ListAdapter.java

public class ListAdapter extends BaseAdapter {

    private Context context;
    private String[] version;
    private LayoutInflater inflater;
    private RadioButton selected = null;

    public ListAdapter(Context context, String[] version) {
        this.context = context;
        this.version = version;
        inflater = LayoutInflater.from(context);
    }

    @Override
    public int getCount() {
        return version.length;
    }

    @Override
    public Object getItem(int position) {
        return version;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(final int position, View view, ViewGroup viewGroup) {

        final Holder holder;
        if (view == null) {
            holder = new Holder();
            view = inflater.inflate(R.layout.row_list, null);

            holder.radioButton = (RadioButton) view.findViewById(R.id.radio1);
            holder.textViewVersion = (TextView) view.findViewById(R.id.textView1);
            holder.btnMore = (Button) view.findViewById(R.id.button1);

            view.setTag(holder);
        } else {
            holder = (Holder) view.getTag();
        }

        holder.textViewVersion.setText(version[position]);

        //by default last radio button selected
        if (position == getCount() - 1) {
            if (selected == null) {
                holder.radioButton.setChecked(true);
                selected = holder.radioButton;
            }
        }

        holder.radioButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                if (selected != null) {
                    selected.setChecked(false);
                }
                holder.radioButton.setChecked(true);
                selected = holder.radioButton;
            }
        });       
    }

    private class Holder {
        private RadioButton radioButton;
        private TextView textViewVersion;
        private Button btnMore;
    }
}

Hope this helps you :)