Android 中利用广播接收器（BroadCastReceiver）来接收定时响铃的闹铃信息
刚开始做东西得时候很不了解android中一些组件的应用方法，找了一个闹钟的小例子来更好的理解广播的接收.
应用程序的界面是这样的，这个例子是用闹钟的制定与解除来穿插broadcast Receiver 的知识，不说废话了，先看下应用程序的界面：
点击设定闹钟的按钮，弹出来一个设置时间的对话框，你选择时间之后会弹出一个Toast告诉你定的时间时多少，然后到时间之后弹出对话框提示时间到。先看图：
是一个小闹钟的完整过程，代码中关键的部分就是用到AlarmManager控制时间和PendingIntent 捕获要执行的广播，先贴代码再详细讲解代码。
1
mButton1
.
setOnClickListener(
new
View
.
OnClickListener()
2 {
3 public void onClick(View v)
4 { /* 取得按下按钮时的时间做为TimePickerDialog的默认值 */
5 c . setTimeInMillis(System . currentTimeMillis());
6 startCalendar . setTimeInMillis(System . currentTimeMillis());
7 int mHour = c . get(Calendar . HOUR_OF_DAY);
8 int mMinute = c . get(Calendar . MINUTE); /* 跳出TimePickerDialog来设定时间 */
9 new TimePickerDialog(SetAlarmActivity . this ,
10 new TimePickerDialog . OnTimeSetListener()
11 {
12 public void onTimeSet(TimePicker view, int hourOfDay,
13 int minute)
14 { /* 取得设定后的时间，秒跟毫秒设为0 */
15 c . setTimeInMillis(System . currentTimeMillis());
16 c . set(Calendar . HOUR_OF_DAY, hourOfDay);
17 c . set(Calendar . MINUTE, minute);
18 c . set(Calendar . SECOND, 0 );
19 c . set(Calendar . MILLISECOND, 0 );
20 Intent intent = new Intent(SetAlarmActivity . this ,
21 CallAlarm . class );
22 PendingIntent sender = PendingIntent . getBroadcast(
23 SetAlarmActivity . this , 0 , intent, 0 );
24 AlarmManager am;
25 am = (AlarmManager) getSystemService(ALARM_SERVICE);
26 am . set(AlarmManager . RTC_WAKEUP, c . getTimeInMillis(),
27 sender); /* 更新显示的设定闹钟时间 */
28 String tmpS = format(hourOfDay) + " ： " + format(minute);
29 setTime1 . setText(tmpS); /* 以Toast提示设定已完成 */
30 Toast . makeText(SetAlarmActivity . this , " 设定闹钟时间为 " + tmpS,
31 Toast . LENGTH_SHORT) . show();
32
33 }
34 } , mHour, mMinute, true ) . show();
35 }
36 } );
2 {
3 public void onClick(View v)
4 { /* 取得按下按钮时的时间做为TimePickerDialog的默认值 */
5 c . setTimeInMillis(System . currentTimeMillis());
6 startCalendar . setTimeInMillis(System . currentTimeMillis());
7 int mHour = c . get(Calendar . HOUR_OF_DAY);
8 int mMinute = c . get(Calendar . MINUTE); /* 跳出TimePickerDialog来设定时间 */
9 new TimePickerDialog(SetAlarmActivity . this ,
10 new TimePickerDialog . OnTimeSetListener()
11 {
12 public void onTimeSet(TimePicker view, int hourOfDay,
13 int minute)
14 { /* 取得设定后的时间，秒跟毫秒设为0 */
15 c . setTimeInMillis(System . currentTimeMillis());
16 c . set(Calendar . HOUR_OF_DAY, hourOfDay);
17 c . set(Calendar . MINUTE, minute);
18 c . set(Calendar . SECOND, 0 );
19 c . set(Calendar . MILLISECOND, 0 );
20 Intent intent = new Intent(SetAlarmActivity . this ,
21 CallAlarm . class );
22 PendingIntent sender = PendingIntent . getBroadcast(
23 SetAlarmActivity . this , 0 , intent, 0 );
24 AlarmManager am;
25 am = (AlarmManager) getSystemService(ALARM_SERVICE);
26 am . set(AlarmManager . RTC_WAKEUP, c . getTimeInMillis(),
27 sender); /* 更新显示的设定闹钟时间 */
28 String tmpS = format(hourOfDay) + " ： " + format(minute);
29 setTime1 . setText(tmpS); /* 以Toast提示设定已完成 */
30 Toast . makeText(SetAlarmActivity . this , " 设定闹钟时间为 " + tmpS,
31 Toast . LENGTH_SHORT) . show();
32
33 }
34 } , mHour, mMinute, true ) . show();
35 }
36 } );
代码中显示了当点击按钮之后所进行的代码处理，我们获得了设置的时间，然后用了一个Intent,用了一个pendIntent,这个PendIntent在捕获广播的时候才会启动，然后我们将这个PendIntent绑定到AlarmManager上面，有三个参数，一个是时间格式，一个是响铃的时间，一个是闹铃到期时启动sender这个PendIntent对象，然后启动绑定在PendIntent里面的intent，从而启动广播CallAlarm。
在广播接收器CallAlar中，并不是直接执行代码，广播接收器只有一个onReceive方法，在这个方法里面又启动了另外一个Activity。需要说明的是广播接收器是没有界面的.
1
package
com
.
cz;
/*
import相关class
*/
2
3 import android . content . Context;
4 import android . content . Intent;
5 import android . content . BroadcastReceiver;
6 import android . os . Bundle; /* 调用闹钟Alert的Receiver */
7
8 public class CallAlarm extends BroadcastReceiver
9 {
10 @Override
11 public void onReceive(Context context, Intent intent)
12 { /* create Intent，调用AlarmAlert.class */
13 Intent i = new Intent(context, AlarmAlert . class );
14 Bundle bundleRet = new Bundle();
15 bundleRet . putString( " STR_CALLER " , " " );
16 i . putExtras(bundleRet);
17 i . addFlags(Intent . FLAG_ACTIVITY_NEW_TASK);
18 context . startActivity(i);
19 }
20 }
2
3 import android . content . Context;
4 import android . content . Intent;
5 import android . content . BroadcastReceiver;
6 import android . os . Bundle; /* 调用闹钟Alert的Receiver */
7
8 public class CallAlarm extends BroadcastReceiver
9 {
10 @Override
11 public void onReceive(Context context, Intent intent)
12 { /* create Intent，调用AlarmAlert.class */
13 Intent i = new Intent(context, AlarmAlert . class );
14 Bundle bundleRet = new Bundle();
15 bundleRet . putString( " STR_CALLER " , " " );
16 i . putExtras(bundleRet);
17 i . addFlags(Intent . FLAG_ACTIVITY_NEW_TASK);
18 context . startActivity(i);
19 }
20 }
启动另外一个Activity,是弹出闹铃时间到时的提示对话框，看下代码：
1
package
com
.
cz;
/*
import相关class
*/
2
3 import android . app . Activity;
4 import android . app . AlertDialog;
5 import android . content . DialogInterface;
6 import android . os . Bundle;
7
8 public class AlarmAlert extends Activity
9 {
10 @Override
11 protected void onCreate(Bundle savedInstanceState)
12 {
13 super . onCreate(savedInstanceState); /* 跳出的闹铃警示 */
14 new AlertDialog . Builder(AlarmAlert . this ) . setIcon(R . drawable . clock)
15 . setTitle( " 闹钟响了!! " ) . setMessage( " 赶快起床吧!!! " ) . setPositiveButton(
16 " 关掉他 " , new DialogInterface . OnClickListener()
17 {
18 public void onClick(DialogInterface dialog,
19 int whichButton)
20 { /* 关闭Activity */
21 AlarmAlert . this . finish();
22 }
23 } ) . show();
24 }
25 }
2
3 import android . app . Activity;
4 import android . app . AlertDialog;
5 import android . content . DialogInterface;
6 import android . os . Bundle;
7
8 public class AlarmAlert extends Activity
9 {
10 @Override
11 protected void onCreate(Bundle savedInstanceState)
12 {
13 super . onCreate(savedInstanceState); /* 跳出的闹铃警示 */
14 new AlertDialog . Builder(AlarmAlert . this ) . setIcon(R . drawable . clock)
15 . setTitle( " 闹钟响了!! " ) . setMessage( " 赶快起床吧!!! " ) . setPositiveButton(
16 " 关掉他 " , new DialogInterface . OnClickListener()
17 {
18 public void onClick(DialogInterface dialog,
19 int whichButton)
20 { /* 关闭Activity */
21 AlarmAlert . this . finish();
22 }
23 } ) . show();
24 }
25 }
如果条件允许，还可以在响铃时加上震动，铃声等选项..
本文转自HDDevTeam 51CTO博客，原文链接：http://blog.51cto.com/hddev/628428，如需转载请自行联系原作者
