服务通知的无效渠道：通知

Question

只要我使用 Android Emulator 进行测试，我的代码就可以正常工作，但是一旦我构建它并尝试在我的手机上使用它，我就会收到以下错误：

    An uncaught Exception occurred on "main" thread.
Bad notification for startForeground: java.lang.RuntimeException: invalid channel for service notification: Notification(channel=channel_01 pri=0 contentView=null vibrate=null sound=null defaults=0x0 flags=0x40 color=0x00000000 vis=PRIVATE)

StackTrace:
android.app.RemoteServiceException: Bad notification for startForeground: java.lang.RuntimeException: invalid channel for service notification: Notification(channel=channel_01 pri=0 contentView=null vibrate=null sound=null defaults=0x0 flags=0x40 color=0x00000000 vis=PRIVATE)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1760)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:201)
    at android.app.ActivityThread.main(ActivityThread.java:6806)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)

---

这是我的代码：

@JavaProxy('org.nativescript.nstestandroid.ForegroundService')
class ForegroundService extends android.app.Service {
    onStartCommand(intent, flags, startId) {
        console.log('onStartCommand');
        super.onStartCommand(intent, flags, startId);
        return android.app.Service.START_STICKY;
    }

    onCreate() {
        console.log('onCreate')
        super.onCreate();
        this.startForeground(1, this.getNotification());
    }



 private getNotification() {
        const channel = new android.app.NotificationChannel(
            'channel_01',
            'ForegroundService Channel', 
            android.app.NotificationManager.IMPORTANCE_DEFAULT
        );
       // <const notificationManager = this.getSystemService(android.content.Context.NOTIFICATION_SERVICE) as android.app.NotificationManager;
        //notificationManager.createNotificationChannel(channel);
        const builder = new android.app.Notification.Builder(this.getApplicationContext(), 'channel_01');

        return builder.build();
    }

Answer 1

您需要先创建NotificationChannel，然后才能发布新的Notification。像这样的：

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);

    // Don't see these lines in your code...
    NotificationManager notificationManager = getSystemService(NotificationManager.class);
    notificationManager.createNotificationChannel(channel);
}

您只是在创建新频道（作为对象），但从不调用createNotificationChannel

您可能在模拟器上创建了通知通道，但在设备上没有。出于兼容性目的，某些具有早期操作系统版本的设备也可能会自动创建“默认”通知通道，但较新的操作系统版本可能需要在显示通知之前创建通道

HERE中的一些指南

Answer 2

1. 像这样创建应用程序类

   public class App extends Application {
   
   public static final String CHANNEL_ID = "exampleServiceChannel";
   
   @Override
   public void onCreate() {
       super.onCreate();
       createNotificationChannel();
   }
   
   private void createNotificationChannel() {
       if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){
           NotificationChannel serviceChannel = new NotificationChannel(CHANNEL_ID, "Example Service Channel",NotificationManager.IMPORTANCE_DEFAULT);
           NotificationManager notificationManager = getSystemService(NotificationManager.class);
           notificationManager.createNotificationChannel(serviceChannel);
   
       }
   }
   }
   

2. 在您的服务类中创建通知并调用 startForeground

Intent notificationIntent =  new Intent(this, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(this,
                0, notificationIntent, 0);        
Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
            .setContentTitle("Example Service")
            .setContentText(userInput)
            .setSmallIcon(R.drawable.ic_android)
            .setContentIntent(pendingIntent)
            .build();
    
    
        startForeground(1,notification);

1. 非常重要 -> 忘记在清单文件中提及您的应用程序类 App -> android:name=".App"

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.example.androidservicestemplate">
    
        <uses-permission android:name="android.permission.FOREGROUND_SERVICE" /> 
    <application
            android:name=".App"
            android:allowBackup="true"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:roundIcon="@mipmap/ic_launcher_round"
            android:supportsRtl="true"
            android:theme="@style/AppTheme">
            <activity android:name=".MainActivity"></activity>
            <service android:name=".ExampleService" />
        </application>
    
    </manifest>