android系统托盘中的通知，不起作用答案

【问题标题】：Notification in android system tray, does not workandroid系统托盘中的通知，不起作用
【发布时间】：2021-06-05 09:30:24
【问题描述】：

我已经设置了接收通知的代码，但它不起作用：

                String ns = Context.NOTIFICATION_SERVICE;
                NotificationManager notificationManager = (NotificationManager) getSystemService(ns);
                int icon = R.drawable.messages_received;
                CharSequence contentTitle = "TITLE";
                Intent notificationIntent = new Intent(this, MainActivity.class);
                PendingIntent contentIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);

                Context context = getApplicationContext();
                NotificationCompat.Builder builder = new NotificationCompat.Builder(context);

                Notification notification  = builder
                        .setContentIntent(contentIntent)
                        .setSmallIcon(icon)
                        .setWhen( System.currentTimeMillis())
                        .setContentTitle(contentTitle)
                        .setContentText(message.getMessage())
                        .build();

                notification.flags |= Notification.FLAG_AUTO_CANCEL;
                notification.defaults |= Notification.DEFAULT_SOUND;
                notification.defaults |= Notification.DEFAULT_VIBRATE;
                notification.defaults |= Notification.DEFAULT_LIGHTS;

                final int NOTIFY = 1;
                notificationManager.notify(NOTIFY, notification);

我在我的 MainActivity 上使用它，并在电话处于待机状态时尝试了它。我该如何解决？它需要一些其他代码吗？我遵循了这个指南：http://www.dre.vanderbilt.edu/~schmidt/android/android-4.0/out/target/common/docs/doc-comment-check/guide/topics/ui/notifiers/notifications.html

谢谢

【问题讨论】：

您测试的操作系统版本是什么？
Android 10，但我也想要旧操作系统的解决方案，谢谢

标签： java android notifications

【解决方案1】：

     public static final String CHANNEL_ID = "com.example.test.services";
     public static final String CHANNEL_NAME = "UploadBackgroundService";
     public static final int FOREGROUND_ID = 1339;
    
    private void createAndShowForegroundNotification() {
    
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
    
                NotificationChannel chan = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_NONE);
                chan.setLockscreenVisibility(Notification.VISIBILITY_PRIVATE);
                manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
                assert manager != null;
                manager.createNotificationChannel(chan);
    
                notificationBuilder = new NotificationCompat.Builder(this, CHANNEL_ID);
                Notification notification = notificationBuilder
                        .setContentTitle("Image upload service")
                        .setContentText("Uploading Images...")
                        .setPriority(NotificationManager.IMPORTANCE_HIGH)
                        .setCategory(Notification.CATEGORY_SERVICE)
                        .setOngoing(true)
                        .setSmallIcon(R.drawable.logoo)
                        .setAutoCancel(false)
                        .build();
                manager.notify(FOREGROUND_ID, notification);
            } else {
                manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
                notificationBuilder = new NotificationCompat.Builder(this,CHANNEL_ID )
                        .setDefaults(Notification.DEFAULT_ALL)
                        .setPriority(NotificationCompat.PRIORITY_HIGH)
                        .setContentTitle("Image upload service")
                        .setContentText("Uploading Images...")
                        .setOngoing(true)
                        .setSmallIcon(R.drawable.logoo)
                        .setAutoCancel(false);
                Notification notification = notificationBuilder.build();
                manager.notify(FOREGROUND_ID, notification);
            }
        }

try this code.replace the required parameters with your own.

【讨论】：

Krishan Madushanka，startForeground 代表什么？它缺少一些代码..
我尝试了您的代码，但它也不起作用，我看到 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) { .... 计算结果为 true，但没有通知出现，为什么？
也尝试设置.setLargeIcon(BitmapFactory.decodeResource(getResources(),R.mipmap.logo)) .setBadgeIconType(R.mipmap.logo)

【解决方案2】：

我用这段代码解决了这个问题：

public static final String CHANNEL_ID = "messages-id";
public static final String CHANNEL_NAME = "messages";
public static final int FOREGROUND_ID = 1339;

private void notifyForeground(String message) {
    NotificationManager manager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {

        NotificationChannel chan = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
        assert manager != null;
        manager.createNotificationChannel(chan);

        Intent notificationIntent = new Intent(this, MainActivity.class);
        PendingIntent contentIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, CHANNEL_ID);
        Notification notification = notificationBuilder
                .setContentIntent(contentIntent)
                .setDefaults(Notification.DEFAULT_ALL)
                .setContentTitle("New message")
                .setContentText(message)
                .setPriority(NotificationManager.IMPORTANCE_HIGH)
                .setCategory(Notification.CATEGORY_MESSAGE)
                .setSmallIcon(R.drawable.messages_received)
                .setAutoCancel(true)
                .build();
        manager.notify(FOREGROUND_ID, notification);
    } else {
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this,CHANNEL_ID )
                .setDefaults(Notification.DEFAULT_ALL)
                .setPriority(NotificationCompat.PRIORITY_HIGH)
                .setContentTitle("New message")
                .setContentText(message)
                .setSmallIcon(R.drawable.messages_received)
                .setAutoCancel(true);
        Notification notification = notificationBuilder.build();
        manager.notify(FOREGROUND_ID, notification);
    }
}

谢谢

【讨论】：