Android框架中的广播机制

// 定义广播的意图过滤器
private String action = "com.xxx.demo.Broadcast.STATUS_CHANGED";
// 发送广播
Intent intent = new Intent();
intent.setAction(action);
ServiceSimulation.this.sendBroadcast(intent);

public class ServiceBroadcastReceiver extends BroadcastReceiver{

    /**
     * 本对象在接收到广播时创建，并执行onReceive方法，
     * 一旦onReceive方法执行完毕（return），
     * 本对象即被销毁（阅后即焚机制）。
     * 下次接收到广播时会再次重新创建本对象，再次执行阅后即焚机制。
     */
    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO do someing...
    }

}

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        
        <receiver android:name=".ServiceBroadcastReceiver">
            <intent-filter >
                <action android:name="com.xxx.demo.Broadcast.STATUS_CHANGED"/>
            </intent-filter>
        </receiver>
        <!-- Exported receiver does not require permission -->
    </application>

    // 注册ServiceSimulation的广播接收器
    ServiceBroadcastReceiver receiver;

    // STATUS_CHANGED是ServiceSimulation发送广播的频道
    private final static String STATUS_CHANGED = "com.xxx.demo.Broadcast.STATUS_CHANGED";

    /**
     * 注册ServiceSimulation的广播接收器
     */
    private void registerServiceBroadcastReceiver(){
        
        // 实例化广播接收器对象receiver，该对象为类成员变量
        receiver = new ServiceBroadcastReceiver();
        
        // 创建意图过滤器对象
        IntentFilter filter = new IntentFilter();
        
        // 为意图过滤器对象设置Action，即：广播频道
        filter.addAction(STATUS_CHANGED);
        
        // 注册该广播接收器
        MainActivity.this.registerReceiver(receiver, filter);
        
    }

    /**
     * 注销ServiceSimulation的广播接收器
     */
    private void unregisterServiceBroadcastReceiver(){
        
        // 注销广播接收器对象receiver，该对象为类成员变量
        MainActivity.this.unregisterReceiver(receiver);
    }