在 Delphi 10.3 中启动前台服务

Question

I need to start a service for Android 9 in foreground but notification is not working. I tried this code but this error occurs when the service starts: "invalid channel for service notification". I am using Delphi 10.3. Any idea to solve this issue?

procedure TServiceModule.StartForeground;
var
  LBuilder: JNotificationCompat_Builder;
begin
  LBuilder := TJNotificationCompat_Builder.JavaClass.init(TAndroidHelper.Context);
  LBuilder.setAutoCancel(True);
  LBuilder.setContentTitle(StrToJCharSequence('Title'));
  LBuilder.setContentText(StrToJCharSequence('Text'));
  LBuilder.setSmallIcon(TAndroidHelper.Context.getApplicationInfo.icon);
  LBuilder.setTicker(StrToJCharSequence('Caption'));
  TJService.Wrap(System.JavaContext).startForeground(1413, LBuilder.build);
end;

Answer 1

Now this code would take several pages to describe in full. You're welcome to use whatever parts suit your app. This is working code from my app that's running on dozens of phones from 4.4.2 up. This code compiles under Delphi 10.2.3 for API 14 and Delphi 10.3.3 for API 28.

uses
   Androidapi.JNI.App,
   Androidapi.JNI.GraphicsContentViewText,
   Androidapi.JNI.Support;

function TMainService.AndroidServiceStartCommand(const Sender: TObject;
     const Intent: JIntent; Flags, StartId: Integer): Integer;
var
  ExtraData: String;
  {$ifdef VER330}
  ServiceChannel: JNotificationChannel;
  NotificationManager: JNotificationManager;
  Obj: JObject;
  {$endif}
  NewIntent: JIntent;
  ncb: JNotificationCompat_Builder;
  ntf: JNotification;
  PendingIntent: JPendingIntent;

begin

   Result := TJService.JavaClass.START_NOT_STICKY;

   // can't ref .O on earlier phones, must hardcode
  if TJBuild_VERSION.JavaClass.SDK_INT > 26 then // JBuild_VERSION_CODES.JavaClass.O                    begin
    {$ifdef VER330}
    // new ways for SDK > 26 (won't be called when API < 26 anyways)
    ServiceChannel := TJNotificationChannel.JavaClass.init(
      StringtoJString(CHANNEL_ID),
      StrToJCharSequence('My Service Channel'),
      TJNotificationManager.JavaClass.IMPORTANCE_DEFAULT
    );

    Obj := TAndroidHelper.Context.getSystemService(
    TJContext.JavaClass.NOTIFICATION_SERVICE);
    NotificationManager := TJNotificationManager.Wrap(Obj);
    NotificationManager.createNotificationChannel(ServiceChannel);

    NewIntent:= TAndroidHelper.Context.getPackageManager().getLaunchIntentForPackage(
      TAndroidHelper.Context.getPackageName());
    NewIntent.setAction(TJIntent.JavaClass.ACTION_MAIN);
    NewIntent.addCategory(TJIntent.JavaClass.CATEGORY_LAUNCHER);
    NewIntent.addFlags(TJIntent.JavaClass.FLAG_ACTIVITY_NEW_TASK);

    PendingIntent := TJPendingIntent.JavaClass.getActivity(
      TAndroidHelper.Context, 0, NewIntent,
      TJIntent.JavaClass.FLAG_ACTIVITY_NEW_TASK
    );

    ncb := TJNotificationCompat_Builder.JavaClass.init(
      TAndroidHelper.Context,
      StringToJString(CHANNEL_ID)
    );

   ncb.setContentTitle(StrToJCharSequence('MyService'));
   // ncb.setTicker(StrToJCharSequence('MyCommsService')); // can't remember why this is commented out to be honest
   ncb.setSmallIcon(JavaService.getApplicationInfo.icon);
   ncb.setContentIntent(PendingIntent);
   ncb.setOngoing(True);
   ntf := ncb.build;
   {$endif VER330}
 end
 else
 begin
   {$ifdef ORDINARY_NOTIFICATION}
    PendingIntent := TJPendingIntent.JavaClass.getActivity(
      JavaService.getApplicationContext, 0, Intent, 0
    );
    ntf := TJNotification.Create;
    ntf.icon := JavaService.getApplicationInfo.icon;
    ntf.setLatestEventInfo(
      JavaService.getApplicationContext,
      StrToJCharSequence('MyService'),
      StrToJCharSequence('MyCommsService'), PendingIntent);
    {$endif}
    {$ifdef CLICKABLE_NOTIFICATION}
    NewIntent:= TAndroidHelper.Context.getPackageManager().getLaunchIntentForPackage(
      TAndroidHelper.Context.getPackageName());
    NewIntent.setAction(TJIntent.JavaClass.ACTION_MAIN);
    NewIntent.addCategory(TJIntent.JavaClass.CATEGORY_LAUNCHER);
    NewIntent.addFlags(TJIntent.JavaClass.FLAG_ACTIVITY_NEW_TASK);

    PendingIntent := TJPendingIntent.JavaClass.getActivity(
      TAndroidHelper.Context, 0, NewIntent,
      TJIntent.JavaClass.FLAG_ACTIVITY_NEW_TASK
    );

    ncb := TJNotificationCompat_Builder.JavaClass.init(TAndroidHelper.Context);
    ncb.setContentTitle(StrToJCharSequence('MyService'));
    ncb.setTicker(StrToJCharSequence('MyCommsService'));
    ncb.setSmallIcon(JavaService.getApplicationInfo.icon);
    ncb.setContentIntent(PendingIntent);
    ncb.setOngoing(True);
    ntf := ncb.build;
    {$endif}
  end;

  JavaService.startForeground(StartId, ntf);

  if Intent <> nil then
  begin
     ExtraData := TAndroidHelper.JStringToString(
       Intent.getStringExtra(TAndroidHelper.StringToJString('ExtraData')));
  end;
end;