Android 闹钟

需求：新的平台要实现关机启动，所以要了解一下闹钟的机制

这个链接写得比较详细（我只是动手试了试，毕竟应用不是专长）：http://www.cnblogs.com/mengdd/p/3819806.html

１、AlarmManager　这个是闹钟的核心　

里面有void set函数，void setInexactRepeating函数　通过这些函数来设置　

源码链接：http://download.csdn.net/detail/weiqifa0/9173341

设置闹钟的代码：

package com.example.helloworld;

import java.util.Calendar;

import android.os.Bundle;
import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.app.Service;
import android.app.TimePickerDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TimePicker;
import android.widget.Toast;

public class AlarmTest extends Activity
{
   Button setTime;
   AlarmManager aManager;
   Calendar currentTime = Calendar.getInstance();

   @Override
   public void onCreate(Bundle savedInstanceState)
   {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

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

       aManager = (AlarmManager) getSystemService(
           Service.ALARM_SERVICE);

       setTime.setOnClickListener(new OnClickListener()
       {
           @Override
           public void onClick(View source)
           {
               Calendar currentTime = Calendar.getInstance();
               new TimePickerDialog(AlarmTest.this, 0,
                   new TimePickerDialog.OnTimeSetListener()
                   {
                       @Override
                       public void onTimeSet(TimePicker tp,
                           int hourOfDay, int minute)
                       {
                           Intent intent = new Intent(AlarmTest.this,
                               AlarmActivity.class);
                           PendingIntent pi = PendingIntent.getActivity(
                               AlarmTest.this, 0, intent, 0);
                           Calendar c = Calendar.getInstance();
                           c.set(Calendar.HOUR, hourOfDay);
                           c.set(Calendar.MINUTE, minute);
                           aManager.set(AlarmManager.RTC_WAKEUP,
                               c.getTimeInMillis(), pi); //这个是代码的核心部分
                           Toast.makeText(AlarmTest.this, "设置闹钟成功"
                               , Toast.LENGTH_SHORT).show();
                       }
                   }, currentTime.get(Calendar.HOUR_OF_DAY), currentTime
                       .get(Calendar.MINUTE), false).show();
           }
       });
   }
}

到时后就会去启动另一个Activity ,核心代码如下：

package com.example.helloworld;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.widget.Toast;

/**
* Description:
* ��վ: <a href="http://www.crazyit.org">��Java��</a>
* Copyright (C), 2001-2014, Yeeku.H.Lee
* This program is protected by copyright laws.
* Program Name:
* Date:
* @author Yeeku.H.Lee kongyeeku@163.com
* @version 1.0
*/
public class AlarmActivity extends Activity
{
 MediaPlayer alarmMusic;

 @Override
 public void onCreate(Bundle savedInstanceState)
 {
 super.onCreate(savedInstanceState);
 Toast.makeText(AlarmActivity.this, "设置闹钟时间到"
 , Toast.LENGTH_SHORT).show();
 new AlertDialog.Builder(AlarmActivity.this).setTitle("��")
 .setMessage("１,２")
 .setPositiveButton("ＯＫ", new OnClickListener()
 {
 @Override
 public void onClick(DialogInterface dialog, int which)
 {
 // ֹͣ��
 //alarmMusic.stop();
 // ��Activity 　　//疯狂android里面显示的声音　简单的用法我把声音去掉了
 AlarmActivity.this.finish();
 }
 }).show();
 }
}

AndroidMainfest.xml的代码，每一个Activity都要在里面注册，我第一次写的时候没有注册，结果启动不成功

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.example.helloworld"
 android:versionCode="1"
 android:versionName="1.0" >

 <uses-sdk
 android:minSdkVersion="8"
 android:targetSdkVersion="18" />

 <application
 android:allowBackup="true"
 android:icon="@drawable/ic_launcher"
 android:label="@string/app_name"
 android:theme="@style/AppTheme" >
 <activity
 android:name="com.example.helloworld.AlarmTest"
 android:label="@string/app_name" >
 <intent-filter>
 <action android:name="android.intent.action.MAIN" />

 <category android:name="android.intent.category.LAUNCHER" />
 </intent-filter>
 </activity>
 <activity android:name=".AlarmActivity"/>　//刚开始忘记了这行代码
 </application>

</manifest>