<receiver 
  android:enabled=["true" | "false"]
//此broadcastReceiver能否接收其他App的发出的广播
//默认值是由receiver中有无intent-filter决定的：如果有intent-filter，默认值为true，否则为false
  android:exported=["true" | "false"]
  android:icon="drawable resource"
  android:label="string resource"
//继承BroadcastReceiver子类的类名
  android:name=".mBroadcastReceiver"
//具有相应权限的广播发送者发送的广播才能被此BroadcastReceiver所接收；
  android:permission="string"
//BroadcastReceiver运行所处的进程
//默认为app的进程，可以指定独立的进程
//注：Android四大基本组件都可以通过此属性指定自己的独立进程
  android:process="string" >

//用于指定此广播接收器将接收的广播类型
//本示例中给出的是用于接收网络状态改变时发出的广播
 <intent-filter>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
  </intent-filter>
</receiver>

<receiver 
  //此广播接收者类是mBroadcastReceiver
  android:name=".mBroadcastReceiver" >
  //用于接收网络状态改变时发出的广播
  <intent-filter>
    <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
  </intent-filter>
</receiver>

@Override
 protected void onResume(){
   super.onResume();

  //实例化BroadcastReceiver子类 & IntentFilter
   mBroadcastReceiver mBroadcastReceiver = new mBroadcastReceiver();
   IntentFilter intentFilter = new IntentFilter();

  //设置接收广播的类型
   intentFilter.addAction(android.net.conn.CONNECTIVITY_CHANGE);

  //调用Context的registerReceiver（）方法进行动态注册
   registerReceiver(mBroadcastReceiver, intentFilter);
 }


//注册广播后，要在相应位置记得销毁广播
//即在onPause() 中unregisterReceiver(mBroadcastReceiver)
//当此Activity实例化时，会动态将MyBroadcastReceiver注册到系统中
//当此Activity销毁时，动态注册的MyBroadcastReceiver将不再接收到相应的广播。
 @Override
 protected void onPause() {
   super.onPause();
   //销毁在onResume()方法中的广播
   unregisterReceiver(mBroadcastReceiver);
   }
}