BroadcastReceiver

1.分类

• 普通广播
  范围：整个系统
• 系统广播
  范围：整个系统
• 有序广播
  范围：整个系统
• 本地广播（Local Broadcast）
  背景
  Android中的广播可以跨App直接通信（exported对于有intent-filter情况下默认值为true）
  范围：当前app

//注册应用内广播接收器
//步骤1：实例化BroadcastReceiver子类 & IntentFilter mBroadcastReceiver 
mBroadcastReceiver = new BroadcastReceiver(); 
IntentFilter intentFilter = new IntentFilter(); 

//步骤2：实例化LocalBroadcastManager的实例
localBroadcastManager = LocalBroadcastManager.getInstance(this);

//步骤3：设置接收广播的类型 
intentFilter.addAction(android.net.conn.CONNECTIVITY_CHANGE);

//步骤4：调用LocalBroadcastManager单一实例的registerReceiver（）方法进行动态注册 
localBroadcastManager.registerReceiver(mBroadcastReceiver, intentFilter);

//取消注册应用内广播接收器
localBroadcastManager.unregisterReceiver(mBroadcastReceiver);

//发送应用内广播
Intent intent = new Intent();
intent.setAction(BROADCAST_ACTION);
localBroadcastManager.sendBroadcast(intent);

2.注册方式

• 静态注册

<receiver android:name=".MyReceiver">  
            <intent-filter>  
                <action android:name="android.intent.action.MY_BROADCAST"/>  
                <category android:name="android.intent.category.DEFAULT" />  
            </intent-filter>  
 </receiver>  

• 动态注册

MyReceiver receiver = new MyReceiver();  
IntentFilter filter = new IntentFilter();  
filter.addAction("android.intent.action.MY_BROADCAST");  
registerReceiver(receiver, filter);  

unregisterReceiver(receiver);