通知未显示在android 8+上

Question

使用此代码，我想单击一个按钮并显示一个通知。问题是当我在模拟器api 26+中进行测试时，单击我的按钮时没有出现。在api中，以下26正常显示，没有问题。

btNotify.setOnClickListener(new View.OnClickListener() {
@Override
    public void onClick(View v) {
        notification();
    }
});


public void notification() {
        RemoteViews remoteViews = new 
        RemoteViews(getApplicationContext().getPackageName(),R.layout.notification_collapsed);
        remoteViews.setTextViewText(R.id.title, "Atividade");
        remoteViews.setTextViewText(R.id.act, activity);
        remoteViews.setChronometer(R.id.timer, chronometer.getBase(), chronometer.getFormat(), !running);
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, "notification")
                .setSmallIcon(R.drawable.ic_baseline_access_time_24)
                .setContent(remoteViews)
                .setPriority(NotificationCompat.PRIORITY_DEFAULT);

        NotificationManager notifManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        assert notifManager != null;
        notifManager.notify(1, builder.build());
}