Android通知将不会显示在设备上

我不明白为什么此通知不会显示在设备上。我正在使用的设备正在运行OS9。任何帮助都会很好

 @Override
public void onMessageReceived(RemoteMessage remoteMessage) {

    super.onMessageReceived(remoteMessage);
    Log.d("TestApp", "Notification Received : " + remoteMessage.getData());


    NotificationUtils.getInstance(getApplicationContext()).createChannel(NotificationUtils.DEFAULT_CHANNEL);
    NotificationCompat.Builder notification = buildBasicNotification(getApplicationContext(), remoteMessage.getFrom(), remoteMessage.getData().get("_msg"), NotificationUtils.DEFAULT_CHANNEL);
    displayNotification(notification);

}

public static NotificationCompat.Builder buildBasicNotification(Context context, String title, String msgText, String channelId) {

    NotificationCompat.Builder builder = new NotificationCompat.Builder(context)
            .setContentTitle(title)
            .setContentText(msgText)
            .setSmallIcon(R.drawable.alert_icon)
            .setAutoCancel(false);

    return builder;
}


private void displayNotification(NotificationCompat.Builder builder) {
    NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    manager.notify(0, builder.build());
}

下面是NotificationUtils中的两个重要方法

public static NotificationUtils getInstance(Context context) {
    if (instance == null) {
        instance = new NotificationUtils(context);
    }

    return instance;
}

NotificationUtils(Context context) {
    super(context);
    this.context = context;
    notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        createAlertChannel();
        deleteChannel("Miscellaneous");
    }
}

我终于明白了

错误就在这个方法的内部

public static NotificationCompat.Builder buildBasicNotification(Context context, String title, String msgText, String channelId) {

    NotificationCompat.Builder builder = new NotificationCompat.Builder(context)
            .setContentTitle(title)
            .setContentText(msgText)
            .setSmallIcon(R.drawable.alert_icon)
            .setAutoCancel(false);

    return builder;
}

确保

NotificationCompat.Builder=newnotificationcompat.Builder（上下文）

接受channelId

所以它应该是

NotificationCompat.Builder=newnotificationcompat.Builder（上下文，channelId）

我终于找到了

错误就在这个方法的内部

public static NotificationCompat.Builder buildBasicNotification(Context context, String title, String msgText, String channelId) {

    NotificationCompat.Builder builder = new NotificationCompat.Builder(context)
            .setContentTitle(title)
            .setContentText(msgText)
            .setSmallIcon(R.drawable.alert_icon)
            .setAutoCancel(false);

    return builder;
}

确保

NotificationCompat.Builder=newnotificationcompat.Builder（上下文）

接受channelId

---

所以它应该是

NotificationCompat.Builder=new NotificationCompat.Builder（context，channelId）

日志中有任何错误记录吗？

LogCat中没有任何内容，没有。应用程序不会崩溃，没有try/catch，因此无法捕获任何内容。我运行了调试器，构建器正在生成…LogCat中有任何错误日志吗？LogCat中没有任何内容，没有。应用程序没有崩溃，没有try/catch，因此没有要捕获的内容。我运行了调试器，构建器正在构建。。。