在Android中有很完整的消息通知机制,可以很方便的发送一个通知,然后注册一个receiver去接收这些消息.

  public static void notifyAuthenticationChange(Context ctx, String authority, boolean authenticated) {
        Utils.log("notifyAuthenticationChange,authority="+authority);
    	Intent broadcast = new Intent(ACTION_SOCIAL_AUTH);
        broadcast.putExtra(EXTRA_AUTHORITY, authority);
        broadcast.putExtra(EXTRA_AUTHENTICATED, authenticated);
        ctx.sendBroadcast(broadcast);
    }

	private void registerAuthReceiver() {
		IntentFilter filter = new IntentFilter();
		filter.addAction(AuthObserver.ACTION_SOCIAL_AUTH);
		filter.addCategory(Intent.CATEGORY_DEFAULT);
		registerReceiver(mAuthChangeReceiver, filter);
	}
 
	private BroadcastReceiver mAuthChangeReceiver = new BroadcastReceiver() {
 
		@Override
		public void onReceive(Context context, Intent intent) {
			// TODO Auto-generated method stub
			Utils.log("onReceive,the Auth may changed.intent=" + intent);
		}
	};

unregisterReceiver(mAuthChangeReceiver);