API30上onStartJob未被调用

在JobService中添加onBind方法，并返回一个JobServiceEngine的实例，这样就可以确保onStartJob被调用。如下所示：

public class MyJobService extends JobService {

private MyJobServiceEngine myJobServiceEngine;

@Override
public void onCreate() {
    super.onCreate();
    myJobServiceEngine = new MyJobServiceEngine(this);
}

@Override
public boolean onStartJob(JobParameters jobParameters) {
    // do the job here
    return true;   // true if the job is still running, false if it's done
}

@Override
public boolean onStopJob(JobParameters jobParameters) {
    // stop the job here
    return false;   // false to reschedule the job, true to drop it
}

@Override
public IBinder onBind(Intent intent) {
    return myJobServiceEngine.getBinder();
}

private static class MyJobServiceEngine extends JobServiceEngine {

    private MyJobService myJobService;

    public MyJobServiceEngine(MyJobService jobService) {
        super(jobService);
        myJobService = jobService;
    }

    @Override
    public boolean onStartJob(JobParameters params) {
        return myJobService.onStartJob(params);
    }

    @Override
    public boolean onStopJob(JobParameters params) {
        return myJobService.onStopJob(params);
    }
}

}

最后，在清单文件中注册JobService。

<service android:name=".MyJobService" android:permission="android.permission.BIND_JOB_SERVICE" />