How to implement TwoState using CheckBoxPreference / android development

TwoStatePreferenceActivity.java

public class PreferencesActivity extends PreferenceActivity {
...

  @Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
    // find the CheckBox
		CheckBoxPreference chkbox = (CheckBoxPreference) findPreference(getString(R.string.chkboxid));
    // set OnClick listener
		chkbox.setOnPreferenceClickListener(chkboxListener);
    // update status
		if (chkbox.isChecked() & chkbox.isEnabled()) {
			setStatus((Preference) findPreference(getString(R.string.pref2)), false);
		}
    ...
  }

  // disable or enable preference
	private void setStatus(Preference pref, boolean stats) {		
		pref.setEnabled(stats);		
	}
	
	// Lisener for onclick on seperate ringtone checkbox to disable notification sound checkbox
	private OnPreferenceClickListener chkboxListener = new OnPreferenceClickListener() {
	    public boolean onPreferenceClick(Preference preference) {
				CheckBoxPreference cb = (CheckBoxPreference) preference;
				setStatus((Preference) findPreference(getString(R.string.pref2)), !cb.isChecked());
        return true;
	    }
	};
}