为什么通知无法在某些设备上运行？

Question

我在Android 8更高版本中特别显示通知时遇到问题，我知道它需要设置ChanelID，从我发现的所有引用中，我都必须以这种方式实现，才能设置Chanel ID，但仍然无法正常工作显示通知

在我的Gradle脚本下面

  compileSdkVersion 26
    buildToolsVersion "26.0.0"
    useLibrary 'org.apache.http.legacy'
    defaultConfig {
        applicationId "com.sdept.company.blablabla"
        minSdkVersion 15
        targetSdkVersion 26
        versionCode 9

        versionName "1.9"
        testInstrumentationRunner 
  "android.support.test.runner.AndroidJUnitRunner"
  }

  dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso- 
    core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.google.code.gson:gson:2.4'
    compile 'org.apache.httpcomponents:httpcore:4.2.4'
    compile 'org.apache.httpcomponents:httpmime:4.3'
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:design:25.3.1'
    compile 'pl.droidsonroids.gif:android-gif-drawable:1.1.+'
    compile 'com.android.support:support-v4:25.3.1'
    compile 'com.google.code.gson:gson:2.4'
    compile 'com.google.zxing:core:3.2.1'
    compile 'com.google.android.gms:play-services-maps:11.0.4'
    compile 'com.squareup.picasso:picasso:2.5.2'
    compile 'com.android.support:cardview-v7:25.3.1'
    compile 'com.journeyapps:zxing-android-embedded:3.2.0@aar'
    compile 'com.google.firebase:firebase-messaging:11.0.4'
    testCompile 'junit:junit:4.12'
}
apply plugin: 'com.google.gms.google-services'

这是接收者的通知类

 private void showNotification(String judul,String messageBody, Bitmap image, String kode){
        Intent intent = new Intent(this, Home.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        intent.putExtra("directto", kode);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_ONE_SHOT);
        Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
            int importance = NotificationManager.IMPORTANCE_HIGH;
            NotificationChannel mChannel = new NotificationChannel(CHANNEL_ID, 
            name, importance);
            mChannel.setDescription(Description);
            mChannel.enableLights(true);
            mChannel.setLightColor(Color.RED);
            mChannel.enableVibration(true);
            mChannel.setVibrationPattern(new long[]{100, 200, 300, 400, 500, 
            400, 300, 200, 400});
            mChannel.setShowBadge(true);
            if (notificationManager != null) {
                notificationManager.createNotificationChannel(mChannel);
            }
        }
        if(image != null){
            NotificationCompat.Builder notificationBuilder = new 
            NotificationCompat.Builder(this)
                    .setLargeIcon(convertToBitmap())/*Notification icon 
                    image*/
                    .setSmallIcon(R.drawable.logostar)
                    .setContentTitle(judul)
                    .setContentText(messageBody)
                    .setStyle(new NotificationCompat.BigPictureStyle()
                            .bigPicture(image))
                    .setAutoCancel(true)
                    .setSound(defaultSoundUri)
                    .setContentIntent(pendingIntent);
            notificationManager.notify(0 /* ID of notification */, 
            notificationBuilder.build());
        }
    }

那是我整个脚本的全部内容，只能在android 8更低的版本中使用