要从 onDateChangedListener 中获取年份的星期，您可以使用 Calendar 类来获取所选日期的星期。以下是一个示例代码：

DatePicker datePicker = findViewById(R.id.datePicker);
datePicker.init(year, month, dayOfMonth, new DatePicker.OnDateChangedListener() {
    @Override
    public void onDateChanged(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(year, monthOfYear, dayOfMonth);
        int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);

        switch (dayOfWeek) {
            case Calendar.SUNDAY:
                Log.d("Day of Week", "Sunday");
                break;
            case Calendar.MONDAY:
                Log.d("Day of Week", "Monday");
                break;
            case Calendar.TUESDAY:
                Log.d("Day of Week", "Tuesday");
                break;
            case Calendar.WEDNESDAY:
                Log.d("Day of Week", "Wednesday");
                break;
            case Calendar.THURSDAY:
                Log.d("Day of Week", "Thursday");
                break;
            case Calendar.FRIDAY:
                Log.d("Day of Week", "Friday");
                break;
            case Calendar.SATURDAY:
                Log.d("Day of Week", "Saturday");
                break;
        }
    }
});

在上述代码中，我们首先创建一个 Calendar 实例，并设置为所选日期。然后，我们使用 get(Calendar.DAY_OF_WEEK) 方法获取星期的值，并使用 switch 语句打印相应的星期。您可以根据需要修改代码来执行您想要的操作。