PreferenceFragment动态加载子节点

public class MainActivity extends Activity {
    SharedPreferences sharedPreferences=null;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getFragmentManager().beginTransaction().replace(android.R.id.content, new My_PreferenceFragment(), "111").commit();
    }
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
    public boolean onOptionsItemSelected(MenuItem item) {
       
        return super.onOptionsItemSelected(item);
    }
}

public class My_PreferenceFragment extends PreferenceFragment {
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
        PreferenceScreen a=(PreferenceScreen) getPreferenceManager().findPreference("other");
        Preference preference=new Preference(getActivity());
        preference.setTitle("aaa");
        a.addItemFromInflater(preference);//*******添加代码，要的就是这行
    }
}