Android - 變更DatePicker 按鈕文字
DatePickerDialog dpd = new DatePickerDialog(this, mDateSetListener, mYear_g, mMonth_g, mDay_g);
dpd.setButton(DatePickerDialog.BUTTON_POSITIVE, "Button Text", dpd);
變更線條顏色
http://codeviki.blogspot.tw/2015/09/android-how-to-change-the-divider-color-of-the-datepicker.html
