If you need to perform a data transfer that may take a long time, you can create a JobScheduler job and identify it as a user-initiated data transfer (UIDT) job. UIDT jobs are intended for longer-duration data transfers that are initiated by the device user, such as downloading a file from a remote server. UIDT jobs were introduced with Android 14 (API level 34).
User-initiated data transfer jobs are started by the user. These jobs require a notification, start immediately, and may be able to run for an extended period of time as system conditions allow. You can run several user-initiated data transfer jobs concurrently.
User initiated jobs must be scheduled while the application is visible to the user (or in one of the allowed conditions). After all constraints are met, user initiated jobs can be executed by the OS, subject to system health restrictions. The system may also use the provided estimated payload size to determine how long the job executes.
사용자가 시작한 데이터 전송 작업 예약
To run a user initiated data-transfer job, do the following:
Make sure your app has declared the
JobService
and associated permissions in its manifest:<service android:name="com.example.app.CustomTransferService" android:permission="android.permission.BIND_JOB_SERVICE" android:exported="false"> ... </service>
Also, define a concrete subclass of
JobService
for your data transfer:Kotlin
class CustomTransferService : JobService() { ... }
Java
class CustomTransferService extends JobService() { .... }
Declare the
RUN_USER_INITIATED_JOBS
permission in the manifest:<manifest ...> <uses-permission android:name="android.permission.RUN_USER_INITIATED_JOBS" /> <application ...> ... </application> </manifest>
Call the
setUserInitiated()
method when building aJobInfo
object. (This method is available beginning with Android 14.) We also recommend that you offer a payload size estimate by callingsetEstimatedNetworkBytes()
while creating your job.Kotlin
val networkRequestBuilder = NetworkRequest.Builder() // Add or remove capabilities based on your requirements. // For example, this code specifies that the job won't run // unless there's a connection to the internet (not just a local // network), and the connection doesn't charge per-byte. .addCapability(NET_CAPABILITY_INTERNET) .addCapability(NET_CAPABILITY_NOT_METERED) .build() val jobInfo = JobInfo.Builder(jobId, ComponentName(mContext, CustomTransferService::class.java)) // ... .setUserInitiated(true) .setRequiredNetwork(networkRequestBuilder) // Provide your estimate of the network traffic here .setEstimatedNetworkBytes(1024 * 1024 * 1024) // ... .build()
Java
NetworkRequest networkRequest = new NetworkRequest.Builder() // Add or remove capabilities based on your requirements. // For example, this code specifies that the job won't run // unless there's a connection to the internet (not just a local // network), and the connection doesn't charge per-byte. .addCapability(NET_CAPABILITY_INTERNET) .addCapability(NET_CAPABILITY_NOT_METERED) .build(); JobInfo jobInfo = JobInfo.Builder(jobId, new ComponentName(mContext, CustomTransferService.class)) // ... .setUserInitiated(true) .setRequiredNetwork(networkRequest) // Provide your estimate of the network traffic here .setEstimatedNetworkBytes(1024 * 1024 * 1024) // ... .build();
While the job is being executed, call
setNotification()
on theJobService
object. CallingsetNotification()
makes the user aware that the job is running, both in the Task Manager and in the status bar notification area.When execution is complete, call
jobFinished()
to signal to the system that the job is complete, or that the job should be rescheduled.Kotlin
class CustomTransferService: JobService() { private val scope = CoroutineScope(Dispatchers.IO) @RequiresApi(Build.VERSION_CODES.UPSIDE_DOWN_CAKE) override fun onStartJob(params: JobParameters): Boolean { val notification = Notification.Builder(applicationContext, NOTIFICATION_CHANNEL_ID) .setContentTitle("My user-initiated data transfer job") .setSmallIcon(android.R.mipmap.myicon) .setContentText("Job is running") .build() setNotification(params, notification.id, notification, JobService.JOB_END_NOTIFICATION_POLICY_DETACH) // Execute the work associated with this job asynchronously. scope.launch { doDownload(params) } return true } private suspend fun doDownload(params: JobParameters) { // Run the relevant async download task, then call // jobFinished once the task is completed. jobFinished(params, false) } // Called when the system stops the job. override fun onStopJob(params: JobParameters?): Boolean { // Asynchronously record job-related data, such as the // stop reason. return true // or return false if job should end entirely } }
Java
class CustomTransferService extends JobService{ @RequiresApi(Build.VERSION_CODES.UPSIDE_DOWN_CAKE) @Override public boolean onStartJob(JobParameters params) { Notification notification = Notification.Builder(getBaseContext(), NOTIFICATION_CHANNEL_ID) .setContentTitle("My user-initiated data transfer job") .setSmallIcon(android.R.mipmap.myicon) .setContentText("Job is running") .build(); setNotification(params, notification.id, notification, JobService.JOB_END_NOTIFICATION_POLICY_DETACH) // Execute the work associated with this job asynchronously. new Thread(() -> doDownload(params)).start(); return true; } private void doDownload(JobParameters params) { // Run the relevant async download task, then call // jobFinished once the task is completed. jobFinished(params, false); } // Called when the system stops the job. @Override public boolean onStopJob(JobParameters params) { // Asynchronously record job-related data, such as the // stop reason. return true; // or return false if job should end entirely } }
Periodically update the notification to keep the user informed of the job's status and progress. If you cannot determine the transfer size ahead of scheduling the job, or need to update the estimated transfer size, use the new API,
updateEstimatedNetworkBytes()
to update the transfer size after it becomes known.
Recommendations
To run UIDT jobs effectively, do the following:
Clearly define network constraints and job execution constraints to specify when the job should be executed.
Execute the task asynchronously in
onStartJob()
; for example, you can do this by using a coroutine. If you don't run the task asynchronously, the work runs on the main thread and might block it, which can cause an ANR.To avoid running the job longer than necessary, call
jobFinished()
when the transfer finishes, whether it succeeds or fails. That way, the job doesn't run longer than necessary. To discover why a job was stopped, implement theonStopJob()
callback method and callJobParameters.getStopReason()
.
이전 버전과의 호환성
현재 UIDT 작업을 지원하는 Jetpack 라이브러리는 없습니다. 따라서 Android 14 이상에서 실행 중인지 확인하는 코드로 변경사항을 관리하는 것이 좋습니다. 하위 Android 버전에서는 WorkManager의 포그라운드 서비스 구현을 대체 접근 방식으로 사용할 수 있습니다.
다음은 적절한 시스템 버전을 확인하는 코드의 예입니다.
Kotlin
fun beginTask() { if (Build.VERSION.SDK_INT < Build.VERSION_CODES.UPSIDE_DOWN_CAKE) { scheduleDownloadFGSWorker(context) } else { scheduleDownloadUIDTJob(context) } } private fun scheduleDownloadUIDTJob(context: Context) { // build jobInfo val jobScheduler: JobScheduler = context.getSystemService(Context.JOB_SCHEDULER_SERVICE) as JobScheduler jobScheduler.schedule(jobInfo) } private fun scheduleDownloadFGSWorker(context: Context) { val myWorkRequest = OneTimeWorkRequest.from(DownloadWorker::class.java) WorkManager.getInstance(context).enqueue(myWorkRequest) }
Java
public void beginTask() { if (Build.VERSION.SDK_INT < Build.VERSION_CODES.UPSIDE_DOWN_CAKE) { scheduleDownloadFGSWorker(context); } else { scheduleDownloadUIDTJob(context); } } private void scheduleDownloadUIDTJob(Context context) { // build jobInfo JobScheduler jobScheduler = (JobScheduler) context.getSystemService(Context.JOB_SCHEDULER_SERVICE); jobScheduler.schedule(jobInfo); } private void scheduleDownloadFGSWorker(Context context) { OneTimeWorkRequest myWorkRequest = OneTimeWorkRequest.from(DownloadWorker.class); WorkManager.getInstance(context).enqueue(myWorkRequest) }
UIDT 작업 중지
사용자와 시스템 모두 사용자가 시작한 전송 작업을 중지할 수 있습니다.
작업 관리자에서 사용자에 의해
사용자는 작업 관리자에 표시되는 사용자 시작 데이터 전송 작업을 중지할 수 있습니다.
사용자가 중지를 누르면 시스템은 다음 작업을 실행합니다.
- 실행 중인 다른 모든 작업 또는 포그라운드 서비스를 포함하여 앱의 프로세스를 즉시 종료합니다.
- 실행 중인 작업의
onStopJob()
을 호출하지 않습니다. - 사용자에게 표시되는 작업의 일정이 변경되는 것을 방지합니다.
따라서 작업을 단계적으로 중지하고 일정을 변경할 수 있도록 작업에 관해 게시된 알림에 컨트롤을 제공하는 것이 좋습니다.
특수한 상황에서는 중지 버튼이 작업 관리자의 작업 옆에 표시되지 않거나 작업이 작업 관리자에 아예 표시되지 않을 수 있습니다.
시스템에 의해
Unlike regular jobs, user-initiated data transfer jobs are unaffected by App Standby Buckets quotas. However, the system still stops the job if any of the following conditions occur:
- A developer-defined constraint is no longer met.
- The system determines that the job has run for longer than necessary to complete the data transfer task.
- The system needs to prioritize system health and stop jobs due to increased thermal state.
- The app process is killed due to low device memory.
When the job is stopped by the system for reasons other than low device
memory, the system calls onStopJob()
, and the system retries the job at a time
that the system deems to be optimal. Make sure that your app can persist the
data transfer state even if onStopJob()
isn't called, and that your app can
restore this state when onStartJob()
is called again.
사용자가 시작한 데이터 전송 작업을 예약할 수 있는 조건
Apps can only start a user-initiated data transfer job if the app is in the visible window, or if certain conditions are met:
- If an app can launch activities from the background, it can also launch user-initiated data transfer jobs from the background.
- If an app has an activity in the back stack of an existing task on the Recents screen, that alone doesn't allow a user-initiated data transfer job to run.
If the job is scheduled to run at a time when the necessary conditions are not
met, the job fails and returns a RESULT_FAILURE
error code.
사용자가 시작한 데이터 전송 작업에 허용되는 제약 조건
To support jobs running at optimal points, Android offers the ability to assign constraints to each job type. These constraints are available as of Android 13.
Note: The following table only compares the constraints that vary between each job type. See JobScheduler developer page or work constraints for all constraints.
The following table shows the different job types that support a given job constraint, as well as the set of job constraints that WorkManager supports. Use the search bar before the table to filter the table by the name of a job constraint method.
These are the constraints allowed with user-initiated data transfer jobs:
setBackoffCriteria(JobInfo.BACKOFF_POLICY_EXPONENTIAL)
setClipData()
setEstimatedNetworkBytes()
setMinimumNetworkChunkBytes()
setPersisted()
setNamespace()
setRequiredNetwork()
setRequiredNetworkType()
setRequiresBatteryNotLow()
setRequiresCharging()
setRequiresStorageNotLow()
테스트
다음 목록은 앱의 작업을 수동으로 테스트하는 방법에 관한 몇 가지 단계를 보여줍니다.
- 작업 ID를 가져오려면 빌드 중인 작업에 정의된 값을 가져옵니다.
작업을 즉시 실행하거나 중지된 작업을 다시 시도하려면 터미널 창에서 다음 명령어를 실행합니다.
adb shell cmd jobscheduler run -f APP_PACKAGE_NAME JOB_ID
시스템 상태 또는 할당량 부족 상태로 인해 작업을 강제 종료하는 시스템을 시뮬레이션하려면 터미널 창에서 다음 명령어를 실행합니다.
adb shell cmd jobscheduler timeout TEST_APP_PACKAGE TEST_JOB_ID
참고 항목
추가 리소스
사용자 시작 데이터 전송에 관한 자세한 내용은 다음 추가 리소스를 참고하세요.
- UIDT 통합 사례 연구: Google 지도에서 사용자 시작 데이터 전송 API를 사용하여 다운로드 안정성 10% 개선