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.
Menjadwalkan tugas transfer data yang dimulai pengguna
Untuk menjalankan tugas transfer data yang dimulai pengguna, lakukan hal berikut:
Pastikan aplikasi Anda telah mendeklarasikan
JobService
dan izin terkait dalam manifesnya:<service android:name="com.example.app.CustomTransferService" android:permission="android.permission.BIND_JOB_SERVICE" android:exported="false"> ... </service>
Selain itu, tentukan subclass konkret
JobService
untuk transfer data Anda:Kotlin
class CustomTransferService : JobService() { ... }
Java
class CustomTransferService extends JobService() { .... }
Deklarasikan izin
RUN_USER_INITIATED_JOBS
dalam manifes:<manifest ...> <uses-permission android:name="android.permission.RUN_USER_INITIATED_JOBS" /> <application ...> ... </application> </manifest>
Panggil metode
setUserInitiated()
saat membuat objekJobInfo
. (Metode ini tersedia mulai dari Android 14.) Sebaiknya Anda juga menawarkan estimasi ukuran payload dengan memanggilsetEstimatedNetworkBytes()
saat membuat tugas.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();
Saat tugas sedang dieksekusi, panggil
setNotification()
pada objekJobService
. MemanggilsetNotification()
membuat pengguna menyadari bahwa tugas sedang berjalan, baik di Pengelola Tugas maupun di area notifikasi status bar.Setelah eksekusi selesai, panggil
jobFinished()
untuk memberi tahu sistem bahwa tugas telah selesai, atau tugas tersebut harus dijadwalkan ulang.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 } }
Perbarui notifikasi secara berkala untuk terus memberikan informasi kepada pengguna tentang status dan progres tugas. Jika Anda tidak dapat menentukan ukuran transfer sebelum menjadwalkan tugas, atau perlu memperbarui perkiraan ukuran transfer, gunakan API baru,
updateEstimatedNetworkBytes()
, untuk memperbarui ukuran transfer setelah diketahui.
Rekomendasi
Untuk menjalankan tugas UIDT secara efektif, lakukan hal berikut:
Tentukan batasan jaringan dan batasan eksekusi tugas dengan jelas untuk menentukan kapan tugas harus dieksekusi.
Jalankan tugas secara asinkron di
onStartJob()
; misalnya, Anda dapat melakukannya dengan menggunakan coroutine. Jika Anda tidak menjalankan tugas secara asinkron, pekerjaan akan berjalan di thread utama dan mungkin memblokirnya, yang dapat menyebabkan ANR.Untuk menghindari menjalankan tugas lebih lama dari yang diperlukan, panggil
jobFinished()
saat transfer selesai, baik berhasil maupun gagal. Dengan begitu, tugas tidak berjalan lebih lama dari yang diperlukan. Untuk mengetahui alasan tugas dihentikan, terapkan metode callbackonStopJob()
dan panggilJobParameters.getStopReason()
.
Kompatibilitas mundur
There is currently no Jetpack library that supports UIDT jobs. For this reason, we recommend that you gate your change with code that verifies that you're running on Android 14 or higher. On lower Android versions, you can use WorkManager's foreground service implementation as a fallback approach.
Here's an example of code that checks for the appropriate system version:
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) }
Menghentikan tugas UIDT
Pengguna dan sistem dapat menghentikan tugas transfer yang dimulai pengguna.
Oleh pengguna, dari Pengelola Tugas
The user can stop a user-initiated data transfer job that appears in the Task Manager.
At the moment that the user presses Stop, the system does the following:
- Terminates your app's process immediately, including all other jobs or foreground services running.
- Doesn't call
onStopJob()
for any running jobs. - Prevents user-visible jobs from being rescheduled.
For these reasons, it's recommended to provide controls in the notification posted for the job to allow gracefully stopping and rescheduling the job.
Note that, under special circumstances, the Stop button doesn't appear next to the job in the Task Manager, or the job isn't shown in the Task Manager at all.
Oleh sistem
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.
Kondisi yang diizinkan untuk menjadwalkan tugas transfer data yang dimulai pengguna
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.
Batasan yang diizinkan untuk tugas transfer data yang dimulai pengguna
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()
Pengujian
Daftar berikut menunjukkan beberapa langkah untuk menguji tugas aplikasi secara manual:
- Untuk mendapatkan ID tugas, dapatkan nilai yang ditentukan saat tugas di-build.
Untuk langsung menjalankan tugas, atau untuk mencoba kembali tugas yang dihentikan, jalankan perintah berikut di jendela terminal:
adb shell cmd jobscheduler run -f APP_PACKAGE_NAME JOB_ID
Untuk menyimulasikan penghentian paksa sebuah tugas oleh sistem (karena kondisi sistem atau kondisi kehabisan kuota), jalankan perintah berikut di jendela terminal:
adb shell cmd jobscheduler timeout TEST_APP_PACKAGE TEST_JOB_ID
Lihat juga
Referensi lainnya
Untuk mengetahui informasi selengkapnya tentang transfer data yang dimulai pengguna, lihat referensi tambahan berikut:
- Studi kasus tentang integrasi UIDT: Google Maps meningkatkan keandalan download sebesar 10% menggunakan API transfer data yang dimulai oleh pengguna