You can try this solution. works for me. 
public class MainActivity extends AppCompatActivity implements DatePickerDialog.OnDateSetListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    final Calendar calendar = Calendar.getInstance();
    int year = calendar.get(Calendar.YEAR);
    int month = calendar.get(Calendar.MONTH);
    int day = calendar.get(Calendar.DAY_OF_MONTH);
    DatePickerDialog datepickerdialog = new DatePickerDialog(this,
            AlertDialog.THEME_HOLO_DARK,this,year,month,day);
    colorizeDatePicker(datepickerdialog.getDatePicker());
    datepickerdialog.show();
}
    public static void colorizeDatePicker(DatePicker datePicker) {
        Resources system = Resources.getSystem();
        int dayId = system.getIdentifier("day", "id", "android");
        int monthId = system.getIdentifier("month", "id", "android");
        int yearId = system.getIdentifier("year", "id", "android");
        NumberPicker dayPicker = (NumberPicker) datePicker.findViewById(dayId);
        NumberPicker monthPicker = (NumberPicker) datePicker.findViewById(monthId);
        NumberPicker yearPicker = (NumberPicker) datePicker.findViewById(yearId);
        setDividerColor(dayPicker);
        setDividerColor(monthPicker);
        setDividerColor(yearPicker);
    }
    private static void setDividerColor(NumberPicker picker) {
        if (picker == null)
            return;
        final int count = picker.getChildCount();
        for (int i = 0; i < count; i++) {
            try {
                Field dividerField = picker.getClass().getDeclaredField("mSelectionDivider");
                dividerField.setAccessible(true);
                ColorDrawable colorDrawable = new ColorDrawable(picker.getResources().getColor(R.color.colorAccent));
                dividerField.set(picker, colorDrawable);
                picker.invalidate();
            } catch (Exception e) {
                Log.w("setDividerColor", e);
            }
        }
}
@Override
public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
}
}