set the text size and font to datepicker

DatePicker picker = (DatePicker)findViewById(R.id.dp_date);
        ViewGroup childpicker

         = (ViewGroup)
        findViewById(Resources.getSystem().getIdentifier("month" /*rest is:
        day, year*/, "id", "android"));

        EditText textview = (EditText)
        picker.findViewById(Resources.getSystem().getIdentifier("timepicker_input",
        "id", "android"));
        textview.setTextSize(30);
        textview.setTextColor(Color.GREEN);