将时间选择器中的时间添加到EditTextPrefrence

Question

因此，我正在编写代码以从时间选择器中选择时间a并将此文本添加到edittextprefrence中，由于某种原因，我无法执行此操作。

这是我的代码，用于将时间选择器中的时间添加到edittextprefrence

public class extra extends PreferenceActivity {


//private SharedPreferences.OnSharedPreferenceChangeListener listener;

private EditTextPreference from;
private EditTextPreference to;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.extra);


    final timeSelector ts = new timeSelector();

    from =(EditTextPreference) findPreference("camera-service-time_from");
    //to = (EditTextPreference) findPreference("camera-service-time_to") ;

    from.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
        @Override
        public boolean onPreferenceClick(Preference preference) {
            String put = ts.timeSel();


            Log.d("TEST2:",put);
            from.setText(put);
            setPreferenceScreen(null);
            addPreferencesFromResource(R.xml.extra);
            return false;
        }
    });

}

我的时间选择器代码：

public class timeSelector
{

    int pickdhr;
    int pickdmin;


    String timeSel()
    {

        //here
        Calendar c = Calendar.getInstance();
        int mHour = c.get(Calendar.HOUR_OF_DAY);
        int mMinute = c.get(Calendar.MINUTE);
        TimePickerDialog timePickerDialog = new TimePickerDialog(extra.this,
                new TimePickerDialog.OnTimeSetListener() {

                    @Override
                    public void onTimeSet(TimePicker view, int hourOfDay,
                                          int minute) {

                        pickdhr= hourOfDay;
                       pickdmin= minute;



                    }
                }, mHour, mMinute, true);
        timePickerDialog.show();

        Log.d("TEST3:",pickdhr+":"+pickdmin);
        return pickdhr+":"+ pickdmin;
    }


}

}

因此，我无法将所选时间添加到出现错误的edittextprefrence中？