安卓8通知欄不顯示notification的問題

轉自： https://blog.csdn.net/qq_35749683/article/details/80451791
感謝網友大佬分享。

Notification在android 8.0以上設置時，需要設置渠道信息才能夠正常顯示通知。做實驗的時候懵懵懂懂不知道，改了幾種方式都不行。。。但神奇的是同學沒有設置channel的代碼能在我手機上運行。。。不過設置渠道後終於能顯示通知了，代碼如下：

String id = "my_channel_01";
String name="我是渠道名字";
NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
Notification notification = null;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    NotificationChannel mChannel = new NotificationChannel(id, name, NotificationManager.IMPORTANCE_LOW);

    Log.i(TAG, mChannel.toString());
    notificationManager.createNotificationChannel(mChannel);
    notification = new Notification.Builder(PollService.this)
            .setChannelId(id)
            .setContentTitle("5 new messages")
            .setContentText("hahaha")
            .setSmallIcon(R.mipmap.ic_launcher).build();
} else {
    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(PollService.this)
            .setContentTitle("5 new messages")
            .setContentText("hahaha")
            .setSmallIcon(R.mipmap.ic_launcher)
            .setOngoing(true)
            .setChannelId(id);//無效
    notification = notificationBuilder.build();
}
notificationManager.notify(1,notification);