DatePicker

<DatePicker
        android:id="@+id/date_picker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

public class MainActivity extends Activity {
    private DatePicker datePicker;
    private int year;
    private int monthOfYear;
    private int dayOfMonth;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 初始化
        datePicker = (DatePicker) findViewById(R.id.date_picker);
        // 获取系统时间
        Calendar calendar = Calendar.getInstance();
        year = calendar.get(Calendar.YEAR);
        monthOfYear = calendar.get(Calendar.MONTH);
        dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);
        // DatePicker的事件监听
        datePicker.init(year, monthOfYear, dayOfMonth,
                new OnDateChangedListener() {

                    @Override
                    public void onDateChanged(DatePicker view, int year,
                            int monthOfYear, int dayOfMonth) {
                        Toast.makeText(
                                getApplicationContext(),
                                year + "" + (monthOfYear + 1) + "" + dayOfMonth
                                        + "", Toast.LENGTH_SHORT).show();
                    }
                });
    }

}