在android中用TimePicker和DatePicker或者TimePickerDialog和DatePickerDialog来动态调整时间和日期

首先是用TimePicker和DatePicker来实现动态调整时间和日期，举例如下：

import java.util.Calendar;

import android.app.Activity;

import android.os.Bundle;

import android.widget.DatePicker;

import android.widget.TextView;

import android.widget.TimePicker;

import android.widget.TimePicker.OnTimeChangedListener;

public class A02Activity extends Activity {

private int ayear,amonth,aday,ahour,aminute;

private TimePicker tp;

private DatePicker dp;

private TextView tv;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

Calendar c=Calendar.getInstance();

ayear=c.get(Calendar.YEAR);

amonth=c.get(Calendar.MONTH);

aday=c.get(Calendar.DAY_OF_MONTH);

ahour=c.get(Calendar.HOUR_OF_DAY);

aminute=c.get(Calendar.MINUTE);

tv=(TextView)findViewById(R.id.tv);

dp=(DatePicker)findViewById(R.id.dp);

dp.init(ayear, amonth, aday, new DatePicker.OnDateChangedListener() {

@Override

public void onDateChanged(DatePicker view, int year, int monthOfYear,

int dayOfMonth) {

// TODO Auto-generated method stub

ayear=year;

amonth=monthOfYear;

aday=dayOfMonth;

updateDisplay();

}

});

tp=(TimePicker)findViewById(R.id.tp);

tp.setIs24HourView(true);

tp.setOnTimeChangedListener(new OnTimeChangedListener(){

@Override

public void onTimeChanged(TimePicker view, int hourOfDay, int minute) {

// TODO Auto-generated method stub

ahour=hourOfDay;

aminute=minute;

updateDisplay();

}

});

}

public void updateDisplay(){

tv.setText(new StringBuilder().append(ayear).append("/")

.append(format(amonth+1)).append("/")

.append(format(aday)).append(" ")

.append(format(ahour)).append(":")

.append(format(aminute)));

}

public String format(int x){

String s=""+x;

if(s.length()==1){

s="0"+s;

}

return s;

}

}

其中res/layout/main.xml为：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical" >

<TextView

android:id="@+id/tv"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:text="@string/hello" />

<DatePicker

android:id="@+id/dp"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

/>

<TimePicker

android:id="@+id/tp"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

/>

</LinearLayout>

从上面的例子可以看出TimePicker的setOnTimeChangedListener()和DatePicker的setOnDateChangedListener()方法是不太一样的，TimePicker的是

直接以setOnTimeChangedListener()方法来处理时间动态改变时所要做的操作；而DatePicker是以init()方法来初始DatePicker的年、月、日和setOnDateChangedListener()处理日期动态改变时所要做的操作的。

在旧版本的Android SDK(1.0r2以前的SDK版本)中，DatePicker对象有提供setOnDateChangedListener()这个方法，但是在新版本的SDK（1.0r2），这个方法被删除了，，所以要实现OnDateChangedListener()时，必须以init()方式来重写OnDateChangedListener()；而TimePicker则直接以setOnTimeChangedListener()来实现即可。

用TimePickerDialog和DatePickerDialog来实现动态调整时间和日期例子如下所示：

import java.util.Calendar;

import android.app.Activity;

import android.app.DatePickerDialog;

import android.app.DatePickerDialog.OnDateSetListener;

import android.app.TimePickerDialog;

import android.app.TimePickerDialog.OnTimeSetListener;

import android.graphics.Color;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.DatePicker;

import android.widget.TimePicker;

public class A03Activity extends Activity {

private Button b01,b02;

private int myear,mmonth,mday,mhour,mminute;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

b01=(Button)findViewById(R.id.b01);

b01.setText("设定时间");

b01.setBackgroundColor(Color.BLUE);

b02=(Button)findViewById(R.id.b02);

b02.setText("设定日期");

b02.setBackgroundColor(Color.GREEN);

Calendar c=Calendar.getInstance();

myear=c.get(Calendar.YEAR);

mmonth=c.get(Calendar.MONTH);

mday=c.get(Calendar.DAY_OF_MONTH);

mhour=c.get(Calendar.HOUR_OF_DAY);

mminute=c.get(Calendar.MINUTE);

b01.setOnClickListener(new OnClickListener(){

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

new TimePickerDialog(A03Activity.this,new OnTimeSetListener(){

@Override

public void onTimeSet(TimePicker view, int hourOfDay,

int minute) {

// TODO Auto-generated method stub

mhour=hourOfDay;

mminute=minute;

}

},mhour,mminute,true).show();

}

});

b02.setOnClickListener(new OnClickListener(){

@Override

public void onClick(View v) {

// TODO Auto-generated method stub

new DatePickerDialog(A03Activity.this,new OnDateSetListener(){

@Override

public void onDateSet(DatePicker view, int year,

int monthOfYear, int dayOfMonth) {

// TODO Auto-generated method stub

myear=year;

mmonth=monthOfYear;

mday=dayOfMonth;

}

},myear,mmonth,mday).show();

}

});

}

}

其中res/layout/main.xml如下所示：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:orientation="vertical" >

<TextView

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:text="@string/hello" />

<Button

android:id="@+id/b01"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

/>

<Button

android:id="@+id/b02"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

/>

</LinearLayout>

DatePickerDialog和TimePickerDialog是Android提供的另外两种来实现动态修改日期时间的功能：DatePicker与TimePicker是直接显示在屏幕画面上，而DatePickerDialog与TimePickerDialog对象则是弹出Dialog的方式来显示。

这两种方式都可以实现动态修改日期时间的功能。