android 关于EditTextPreference光标位置

public class SystemSettingPreference extends PreferenceActivity

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protected void onCreate(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onCreate(savedInstanceState);
  addPreferencesFromResource(R.xml.system_setting);

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public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen,
   Preference preference) {
  // TODO Auto-generated method stub
   super.onPreferenceTreeClick(preferenceScreen, preference);
   Preference tmp_pre = (Preference)manager.findPreference(preference.getKey());
  //判断是否是EditTextPreference
   if(tmp_pre instanceof EditTextPreference)
   {
    tmp_pre = (EditTextPreference) tmp_pre;
    EditText ed = ((EditTextPreference) tmp_pre).getEditText();
     
     Editable etable = ed.getText(); 
     Selection.setSelection(etable, etable.length());//光标置位
   
   }
   return true;
 }

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