无法在 android 中创建通知

Question

我输入了以下函数以在 android 中获取通知。

但我收到一条错误消息，显示无法post 频道“null”上的通知。我知道我遗漏了一些代码，这些代码似乎是为某些较新版本的设备运行插入的。

我能得到要插入的确切代码吗？

void create_notification(String string){
        Intent intent = new Intent(this, MainActivity.class);
    TaskStackBuilder stackBuilder = TaskStackBuilder.create(this);
    stackBuilder.addParentStack(MainActivity.class);
    stackBuilder.addNextIntent(intent);
    PendingIntent pendingIntent =
            stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT
            );
    Notification notification = new Notification.Builder(this)
            .setSmallIcon(R.mipmap.ic_launcher)
            .setContentTitle(getString(R.string.app_name))
            .setAutoCancel(true)
            .setPriority(Notification.PRIORITY_MAX)
            .setDefaults(Notification.DEFAULT_VIBRATE)
            .setContentIntent(pendingIntent)
            .setContentText(string)
            .build();
    NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(NOTIFICATION_ID, notification);
}

Answer 1

documentation（搜索词“android 通知渠道”在 google 上的第一个结果）给出了以下示例：

private void createNotificationChannel() {
    // Create the NotificationChannel, but only on API 26+ because
    // the NotificationChannel class is new and not in the support library
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        CharSequence name = getString(R.string.channel_name);
        String description = getString(R.string.channel_description);
        int importance = NotificationManager.IMPORTANCE_DEFAULT;
        NotificationChannel channel = new NotificationChannel(CHANNEL_ID, name, importance);
        channel.setDescription(description);
        // Register the channel with the system; you can't change the importance
        // or other notification behaviors after this
        NotificationManager notificationManager = getSystemService(NotificationManager.class);
        notificationManager.createNotificationChannel(channel);
    }
}

然后您需要在通知中指定频道 ID：

Notification notification = new Notification.Builder(this, CHANNEL_ID)
   ...

你试过吗？

Answer 2

在您的构建器中，您可以添加频道 ID，例如：

Notification notification = new Notification.Builder(this)
            .setSmallIcon(R.mipmap.ic_launcher)
            .setContentTitle(getString(R.string.app_name))
            .setAutoCancel(true)
            .setChannelId("base_channel") //<-- set the name you feel is proper to your project
            .setPriority(Notification.PRIORITY_MAX)
            .setDefaults(Notification.DEFAULT_VIBRATE)
            .setContentIntent(pendingIntent)
            .setContentText(string)
            .build();

无法在 android 中创建通知

Unable to create notifications in android

java

android

android-notifications