datetimepicker一个不错的日历效,选中和选择日历效果都很不错，
实用的时候直接可以把datetimepicker-library这个引入到项目，调用的地方在实现
TimePickerDialog.OnTimeSetListener接口。
大体实现由DatePickerDialog类来封装，调用如下
DatePickerDialog datePickerDialog = DatePickerDialog.newInstance(this, calendar.get(Calendar.YEAR),
calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH), isVibrate());

datePickerDialog.setVibrate(isVibrate());
datePickerDialog.setYearRange(1985, 2028);
datePickerDialog.setCloseOnSingleTapDay(isCloseOnSingleTapDay());
datePickerDialog.show(getSupportFragmentManager(), DATEPICKER_TAG);