Android弹出DatePickerDialog并获取值的方法

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:paddingBottom="@dimen/activity_vertical_margin"
  android:paddingLeft="@dimen/activity_horizontal_margin"
  android:paddingRight="@dimen/activity_horizontal_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  tools:context=".MainActivity" >
 
  <TextView
    android:id="@+id/tvShowDialog"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="76dp"
    android:text="日期" />
 
</RelativeLayout>

package com.example.textcalendar;
 
import java.util.Calendar;
 
import android.os.Bundle;
import android.app.Activity;
import android.app.DatePickerDialog;
import android.app.DatePickerDialog.OnDateSetListener;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.DatePicker;
import android.widget.TextView;
 
public class MainActivity extends Activity implements OnClickListener{
 private TextView tvShowDialog;
 private Calendar cal;
 private int year,month,day;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 
 //获取当前日期
 getDate();
 
 tvShowDialog=(TextView) findViewById(R.id.tvShowDialog);
 tvShowDialog.setOnClickListener(this);
 
 }
 
 //获取当前日期
 private void getDate() {
 cal=Calendar.getInstance();
 year=cal.get(Calendar.YEAR);    //获取年月日时分秒 
 Log.i("wxy","year"+year);
 month=cal.get(Calendar.MONTH);  //获取到的月份是从0开始计数
 day=cal.get(Calendar.DAY_OF_MONTH);  
 }
 
 @Override
 public void onClick(View view) {
 switch (view.getId()) {
 case R.id.tvShowDialog:
  OnDateSetListener listener=new OnDateSetListener() {
  
  @Override
  public void onDateSet(DatePicker arg0, int year, int month, int day) {
   tvShowDialog.setText(year+"-"+(++month)+"-"+day);   //将选择的日期显示到TextView中,因为之前获取month直接使用，所以不需要+1，这个地方需要显示，所以+1
  }
  };
  DatePickerDialog dialog=new DatePickerDialog(MainActivity.this, 0,listener,year,month,day);//后边三个参数为显示dialog时默认的日期，月份从0开始，0-11对应1-12个月
  dialog.show();
  break;
 
 default:
  break;
 }
 }
 
}