BrodCast的理解

*广播发送方调用 sendBrodcast(Intent intent)，该方法是由ContextWrapper定义的
*广播接受方调用BroadcastReceiver来实现，
广播的动态注册，调用registerReceiver（BroadcastReceiver reciver, IntentFilter filter）
thirdReceiver = new InnerThirdReceiver();
IntentFilter thirdFilter = new IntentFilter();
thirdFilter.addAction("cn.tedu.intent.action.SIMPLE_BROADCAST");
thirdFilter.setPriority(88888);
registerReceiver(thirdReceiver, thirdFilter);