点击通知的时候发送广播，如果通知的id不要设置固定的，如果固定，会只显示一个把上一个覆盖掉

NotificationManager mNotificationManager = (NotificationManager) context
                .getSystemService(NOTIFICATION_SERVICE);
        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(context);
        mBuilder.setContentTitle(title).setContentText(message)
                .setWhen(System.currentTimeMillis())
                .setAutoCancel(true).setDefaults(Notification.DEFAULT_VIBRATE)
                .setSmallIcon(R.drawable.ic_launcher);
        Intent clickIntent = new Intent(context, NotificationClickReceiver.class); //点击通知之后要发送的广播
        clickIntent.putExtra("extras", extras);
        int id = (int) (System.currentTimeMillis());
        PendingIntent contentIntent = PendingIntent.getBroadcast(context, id, clickIntent, PendingIntent.FLAG_UPDATE_CURRENT);
        mBuilder.setContentIntent(contentIntent);
        Notification build = mBuilder.build();
        mNotificationManager.notify(id, build);