Android DatePickerDialog TimepickerDialog

package com.example.myact5;

import java.util.Calendar;

import android.app.DatePickerDialog;
import android.app.DatePickerDialog.OnDateSetListener;
import android.app.TimePickerDialog;
import android.app.TimePickerDialog.OnTimeSetListener;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TimePicker;
import android.widget.Toast;
/**
 * 
 * @Describe: 
 * @package: com.example.myact5
 * @author shaobn
 * @date 2015-9-11 上午9:10:28
 */
public class MainActivity extends ActionBarActivity {
    private Button button;
    private Button button2;
    private Calendar calendar = Calendar.getInstance();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = (Button) this.findViewById(R.id.button1);
        button2 = (Button) this.findViewById(R.id.button2);
        button.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
            TimePickerDialog tpd = new TimePickerDialog(MainActivity.this, new OnTimeSetListener() {
                
                @Override
                public void onTimeSet(TimePicker arg0, int arg1, int arg2) {
                    // TODO Auto-generated method stub
                    Toast.makeText(MainActivity.this,getConstantInstance().hourOfDay+","+ getConstantInstance().minute, 1).show();
                }
            }, getConstantInstance().hourOfDay, getConstantInstance().minute, true);    
            tpd.show();
            }
        });
        button2.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                DatePickerDialog dpd = new DatePickerDialog(MainActivity.this, new OnDateSetListener() {
                    
                    @Override
                    public void onDateSet(DatePicker arg0, int arg1, int arg2, int arg3) {
                        // TODO Auto-generated method stub
                        Toast.makeText(MainActivity.this, arg1+","+(arg2+1)+","+arg3, 1).show();
                    }
                }, getConstantInstance().year, getConstantInstance().monthOfYear, getConstantInstance().dayOfMonth);
                dpd.show();
            }
        });
    }    
    class Constant{
        public int hourOfDay = calendar.get(Calendar.HOUR_OF_DAY);
        public int minute = calendar.get(Calendar.MINUTE);
        public boolean is24HourView = true;
        public int year = calendar.get(Calendar.YEAR);
        public int monthOfYear = calendar.get(Calendar.MONTH);
        public int dayOfMonth = calendar.get(Calendar.DAY_OF_MONTH);
    }
    public Constant getConstantInstance(){
        return new Constant();
    }
}

笔者写的麻烦点，为了练习一下。