androidx.work
Constraints
are met. WorkManager allows observation of work
status and the ability to create complex chains of work.
WorkManager uses an underlying job dispatching service when available based on the following criteria:
- Uses JobScheduler for API 23+
- Uses a custom AlarmManager + BroadcastReceiver implementation for API 14-22
All work must be done in a ListenableWorker
class. A simple
implementation, Worker
, is recommended as the starting point for most
developers. With the optional dependencies, you can also use CoroutineWorker
or
RxWorker
. All background work is given a maximum of ten minutes to finish its execution.
After this time has expired, the worker will be signalled to stop.
There are two types of work supported by WorkManager: OneTimeWorkRequest
and PeriodicWorkRequest
. OneTimeWorkRequests can be chained together into
acyclic graphs. Work is eligible for execution when all of its prerequisites are complete.
If any of its prerequisites fail or are cancelled, the work will never run.
WorkRequests can accept Constraints
, inputs (see
Data
), and backoff criteria. WorkRequests can be tagged with
human-readable Strings (see addTag(String)
), and
chains of work can be given a uniquely-identifiable name with conflict policies. *
Initializing WorkManager
By default, WorkManager is initialized using a ContentProvider
with a default
Configuration
. ContentProviders are created and run before the
Application
object, so this allows the WorkManager singleton to be setup before your
code can run in most cases. This is suitable for most developers. However, you can provide a
custom Configuration
by using Configuration.Provider
or
initialize(android.content.Context, androidx.work.Configuration)
.
WorkManager and its Interactions with the OS
WorkManager BroadcastReceiver
s to monitor Constraints
on devices
before API 23. The BroadcastReceivers are disabled on API 23 and up. In particular, WorkManager
listens to the following Intent
s:
android.intent.action.ACTION_POWER_CONNECTED
android.intent.action.ACTION_POWER_DISCONNECTED
android.intent.action.BATTERY_OKAY
android.intent.action.BATTERY_LOW
android.intent.action.DEVICE_STORAGE_LOW
android.intent.action.DEVICE_STORAGE_OK
android.net.conn.CONNECTIVITY_CHANGE
*
android.intent.action.BOOT_COMPLETED
android.intent.action.TIME_SET
android.intent.action.TIMEZONE_CHANGED
WorkManager uses the following permissions:
android.permission.WAKE_LOCK
to make it can keep the device awake to complete work before API 23android.permission.ACCESS_NETWORK_STATE
to listen to network changes before API 23 and monitor networkConstraints
android.permission.RECEIVE_BOOT_COMPLETED
to listen to reboots and reschedule work properly.
Note that WorkManager may enable or disable some of its BroadcastReceivers at runtime as needed.
This has the side-effect of the system sending ACTION_PACKAGE_CHANGED
broadcasts to your
app. Please be aware of this use case and architect your app appropriately (especially if you
are using widgets - see https://issuetracker.google.com/115575872).
Annotations
ExperimentalExpeditedWork |
An API surface for expedited WorkRequest s.
|
Interfaces
Configuration.Provider |
A class that can provide the Configuration for WorkManager and allow for on-demand
initialization of WorkManager.
|
ForegroundUpdater |
Manages updating Notification s when a ListenableWorker transitions
to running in the context of a foreground Service .
|
Operation |
An object that provides information about the execution of an asynchronous command being
performed by WorkManager .
|
ProgressUpdater |
Updates progress for a ListenableWorker .
|
RunnableScheduler |
Can be used to schedule Runnable s after a delay in milliseconds.
|
Classes
ArrayCreatingInputMerger |
An InputMerger that attempts to merge the inputs, creating arrays when necessary.
|
Configuration |
The Configuration object used to customize WorkManager upon initialization.
|
Configuration.Builder |
A Builder for Configuration s.
|
Constraints |
A specification of the requirements that need to be met before a WorkRequest can run.
|
Constraints.Builder |
A Builder for a Constraints object.
|
Data |
A persistable set of key/value pairs which are used as inputs and outputs for
ListenableWorker s.
|
Data.Builder |
A builder for Data objects.
|
DelegatingWorkerFactory |
A WorkerFactory which delegates to other factories.
|
ForegroundInfo |
The information required when a ListenableWorker runs in the context of a foreground
service.
|
InputMerger |
An abstract class that allows the user to define how to merge a list of inputs to a
ListenableWorker .
|
InputMergerFactory |
A factory object that creates InputMerger instances.
|
ListenableWorker |
A class that can perform work asynchronously in WorkManager .
|
ListenableWorker.Result |
The result of a ListenableWorker 's computation.
|
OneTimeWorkRequest |
A WorkRequest for non-repeating work.
|
OneTimeWorkRequest.Builder |
Builder for OneTimeWorkRequest s.
|
Operation.State |
The lifecycle state of an Operation .
|
Operation.State.FAILURE |
This represents an Operation which has failed.
|
Operation.State.IN_PROGRESS |
This represents an Operation which is in progress.
|
Operation.State.SUCCESS |
This represents an Operation which is successful.
|
OverwritingInputMerger |
An InputMerger that attempts to add all keys from all inputs to the output.
|
PeriodicWorkRequest |
A WorkRequest for repeating work.
|
PeriodicWorkRequest.Builder |
Builder for PeriodicWorkRequest s.
|
RxWorker | RxJava2 interoperability Worker implementation. |
WorkContinuation |
A class that allows you to chain together OneTimeWorkRequest s.
|
Worker |
A class that performs work synchronously on a background thread provided by WorkManager .
|
WorkerFactory |
A factory object that creates ListenableWorker instances.
|
WorkerParameters |
Setup parameters for a ListenableWorker .
|
WorkInfo |
Information about a particular WorkRequest containing the id of the WorkRequest, its
current WorkInfo.State , output, tags, and run attempt count.
|
WorkManager |
WorkManager is a library used to enqueue deferrable work that is guaranteed to execute sometime
after its Constraints are met.
|
WorkQuery |
A specification for querying WorkRequest s.
|
WorkQuery.Builder |
A builder for WorkQuery .
|
WorkRequest |
The base class for specifying parameters for work that should be enqueued in WorkManager .
|
WorkRequest.Builder<B extends Builder<?, ?>, W extends WorkRequest> |
A builder for WorkRequest s.
|
Enums
BackoffPolicy | An enumeration of backoff policies when retrying work. |
ExistingPeriodicWorkPolicy |
An enumeration of the conflict resolution policies available to unique
PeriodicWorkRequest s in case of a collision.
|
ExistingWorkPolicy |
An enumeration of the conflict resolution policies available to unique
OneTimeWorkRequest s in case of a collision.
|
NetworkType |
An enumeration of various network types that can be used as Constraints for work.
|
OutOfQuotaPolicy | An enumeration of policies that help determine out of quota behavior for expedited jobs. |
WorkInfo.State |
The current lifecycle state of a WorkRequest .
|
Annotations
Interfaces
Classes
- ArrayCreatingInputMerger
- Configuration
- Configuration.Builder
- Constraints
- Constraints.Builder
- Data
- Data.Builder
- DelegatingWorkerFactory
- ForegroundInfo
- InputMerger
- InputMergerFactory
- ListenableWorker
- ListenableWorker.Result
- OneTimeWorkRequest
- OneTimeWorkRequest.Builder
- Operation.State
- Operation.State.FAILURE
- Operation.State.IN_PROGRESS
- Operation.State.SUCCESS
- OverwritingInputMerger
- PeriodicWorkRequest
- PeriodicWorkRequest.Builder
- RxWorker
- WorkContinuation
- Worker
- WorkerFactory
- WorkerParameters
- WorkInfo
- WorkManager
- WorkQuery
- WorkQuery.Builder
- WorkRequest
- WorkRequest.Builder
Enums