【代码段】Android Studio使用DatePicker选择日期

布局文件中放一个TextView就好了
Java文件如下：

public class TestDatePickerActivity extends AppCompatActivity {

    private static final String TAG = "TestDatePickerActivity";

    private TextView mDatePicker;
    private DatePickerDialog.OnDateSetListener mDateSetListener;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test_date_picker);
        mDatePicker = findViewById(R.id.tv_datepicker);

        mDatePicker.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Calendar cal = Calendar.getInstance();
                int year = cal.get(Calendar.YEAR);
                int month = cal.get(Calendar.MONTH);
                int day = cal.get(Calendar.DAY_OF_MONTH);

                DatePickerDialog dialog = new DatePickerDialog(
                        TestDatePickerActivity.this,
                        android.R.style.Theme_Holo_Dialog_MinWidth,
                        mDateSetListener,
                        year, month, day);
                dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
                dialog.show();
            }
        });

        mDateSetListener = new DatePickerDialog.OnDateSetListener() {
            @Override
            public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
                Log.d(TAG, "onDateSet: date: " + year + "/" + month + "/" + dayOfMonth);
                int rm = month + 1;
                mDatePicker.setText(year + "/" + rm + "/" + dayOfMonth);
            }
        };
    }
}