WorkManager

abstract class WorkManager


WorkManager is the recommended library for persistent work. Scheduled work is guaranteed to execute sometime after its 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. You can enqueue requests using WorkManager as follows:

WorkManager workManager = WorkManager.getInstance(Context);
workManager.enqueue(new OneTimeWorkRequest.Builder(FooWorker.class).build());
A WorkRequest has an associated id that can be used for lookups and observation as follows:
WorkRequest request = new OneTimeWorkRequest.Builder(FooWorker.class).build();
workManager.enqueue(request);
LiveDatastatus = workManager.getWorkInfoByIdLiveData(request.getId());
status.observe(...);
You can also use the id for cancellation:
WorkRequest request = new OneTimeWorkRequest.Builder(FooWorker.class).build();
workManager.enqueue(request);
workManager.cancelWorkById(request.getId());
You can chain work as follows:
WorkRequest request1 = new OneTimeWorkRequest.Builder(FooWorker.class).build();
WorkRequest request2 = new OneTimeWorkRequest.Builder(BarWorker.class).build();
WorkRequest request3 = new OneTimeWorkRequest.Builder(BazWorker.class).build();
workManager.beginWith(request1, request2).then(request3).enqueue();
Each call to beginWith or beginWith returns a WorkContinuation upon which you can call then or then to chain further work. This allows for creation of complex chains of work. For example, to create a chain like this:
           A
           |
     +----------+
     |          |
     B          C
     |
  +----+
  |    |
D    E             
you would enqueue them as follows:
WorkContinuation continuation = workManager.beginWith(A);
continuation.then(B).then(D, E).enqueue();  // A is implicitly enqueued here
continuation.then(C).enqueue();
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), and chains of work can be given a uniquely-identifiable name (see beginUniqueWork).

Initializing WorkManager

By default, WorkManager auto-initializes itself using a built-in ContentProvider. 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.

Renaming and Removing ListenableWorker Classes

Exercise caution in renaming classes derived from ListenableWorkers. WorkManager stores the class name in its internal database when the WorkRequest is enqueued so it can later create an instance of that worker when constraints are met. Unless otherwise specified in the WorkManager Configuration, this is done in the default WorkerFactory which tries to reflectively create the ListenableWorker object. Therefore, renaming or removing these classes is dangerous - if there is pending work with the given class, it will fail permanently if the class cannot be found. If you are using a custom WorkerFactory, make sure you properly handle cases where the class is not found so that your code does not crash.

In case it is desirable to rename a class, implement a custom WorkerFactory that instantiates the right ListenableWorker for the old class name.

Summary

Nested types

An enumeration of results for updateWork method.

Public functions

abstract WorkContinuation
beginUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: (Mutable)List<OneTimeWorkRequest!>
)

This method allows you to begin unique chains of work for situations where you only want one chain with a given name to be active at a time.

WorkContinuation
beginUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: OneTimeWorkRequest
)

This method allows you to begin unique chains of work for situations where you only want one chain with a given name to be active at a time.

abstract WorkContinuation

Begins a chain with one or more OneTimeWorkRequests, which can be enqueued together in the future using enqueue.

WorkContinuation

Begins a chain with one or more OneTimeWorkRequests, which can be enqueued together in the future using enqueue.

abstract Operation

Cancels all unfinished work.

abstract Operation

Cancels all unfinished work with the given tag.

abstract Operation
cancelUniqueWork(uniqueWorkName: String)

Cancels all unfinished work in the work chain with the given name.

abstract Operation

Cancels work with the given id if it isn't finished.

abstract PendingIntent

Creates a PendingIntent which can be used to cancel a WorkRequest with the given id.

abstract Operation

Enqueues one or more items for background processing.

Operation
enqueue(workRequest: WorkRequest)

Enqueues one item for background processing.

abstract Operation
enqueueUniquePeriodicWork(
    uniqueWorkName: String,
    existingPeriodicWorkPolicy: ExistingPeriodicWorkPolicy,
    periodicWork: PeriodicWorkRequest
)

This method allows you to enqueue a uniquely-named PeriodicWorkRequest, where only one PeriodicWorkRequest of a particular name can be active at a time.

abstract Operation
enqueueUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: (Mutable)List<OneTimeWorkRequest!>
)

This method allows you to enqueue work requests to a uniquely-named WorkContinuation, where only one continuation of a particular name can be active at a time.

Operation
enqueueUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: OneTimeWorkRequest
)

This method allows you to enqueue work requests to a uniquely-named WorkContinuation, where only one continuation of a particular name can be active at a time.

abstract Configuration

Provides the Configuration instance that WorkManager was initialized with.

java-static WorkManager

This function is deprecated.

Call getInstance instead.

java-static WorkManager
getInstance(context: Context)

Retrieves the default singleton instance of WorkManager.

abstract ListenableFuture<Long!>

Gets a ListenableFuture of the last time all work was cancelled.

abstract LiveData<Long!>

Gets a LiveData of the last time all work was cancelled.

abstract ListenableFuture<WorkInfo!>

Gets a ListenableFuture of the WorkInfo for a given work id.

abstract Flow<WorkInfo!>

Gets a Flow of the WorkInfo for a given work id.

abstract LiveData<WorkInfo!>

Gets a LiveData of the WorkInfo for a given work id.

abstract ListenableFuture<(Mutable)List<WorkInfo!>!>
getWorkInfos(workQuery: WorkQuery)

Gets the ListenableFuture of the List of WorkInfo for all work referenced by the WorkQuery specification.

abstract ListenableFuture<(Mutable)List<WorkInfo!>!>

Gets a ListenableFuture of the WorkInfo for all work for a given tag.

abstract Flow<(Mutable)List<WorkInfo!>!>

Gets a Flow of the WorkInfo for all work for a given tag.

abstract LiveData<(Mutable)List<WorkInfo!>!>

Gets a LiveData of the WorkInfo for all work for a given tag.

abstract Flow<(Mutable)List<WorkInfo!>!>

Gets the Flow of the List of WorkInfo for all work referenced by the WorkQuery specification.

abstract ListenableFuture<(Mutable)List<WorkInfo!>!>

Gets a ListenableFuture of the WorkInfo for all work in a work chain with a given unique name.

abstract Flow<(Mutable)List<WorkInfo!>!>

Gets a Flow of the WorkInfo for all work in a work chain with a given unique name.

abstract LiveData<(Mutable)List<WorkInfo!>!>

Gets a LiveData of the WorkInfo for all work in a work chain with a given unique name.

abstract LiveData<(Mutable)List<WorkInfo!>!>

Gets the LiveData of the List of WorkInfo for all work referenced by the WorkQuery specification.

java-static Unit
initialize(context: Context, configuration: Configuration)

Used to do a one-time initialization of the WorkManager singleton with a custom Configuration.

java-static Boolean

Provides a way to check if WorkManager is initialized in this process.

abstract Operation

Prunes all eligible finished work from the internal database.

abstract ListenableFuture<WorkManager.UpdateResult!>

Updates the work with the new specification.

Public functions

beginUniqueWork

Added in 1.0.0
abstract fun beginUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: (Mutable)List<OneTimeWorkRequest!>
): WorkContinuation

This method allows you to begin unique chains of work for situations where you only want one chain with a given name to be active at a time. For example, you may only want one sync operation to be active. If there is one pending, you can choose to let it run or replace it with your new work.

The uniqueWorkName uniquely identifies this set of work.

If this method determines that new work should be enqueued and run, all records of previous work with uniqueWorkName will be pruned. If this method determines that new work should NOT be run, then the entire chain will be considered a no-op.

If any work in the chain fails or is cancelled, all of its dependent work inherits that state and will never run. This is particularly important if you are using APPEND as your ExistingWorkPolicy.

Parameters
uniqueWorkName: String

A unique name which for this chain of work

existingWorkPolicy: ExistingWorkPolicy

An ExistingWorkPolicy; see below for more information

work: (Mutable)List<OneTimeWorkRequest!>

One or more OneTimeWorkRequest to enqueue. REPLACE ensures that if there is pending work labelled with uniqueWorkName, it will be cancelled and the new work will run. KEEP will run the new sequence of work only if there is no pending work labelled with uniqueWorkName. APPEND will create a new sequence of work if there is no existing work with uniqueWorkName; otherwise, work will be added as a child of all leaf nodes labelled with uniqueWorkName.

Returns
WorkContinuation

A WorkContinuation that allows further chaining

beginUniqueWork

Added in 1.0.0
fun beginUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: OneTimeWorkRequest
): WorkContinuation

This method allows you to begin unique chains of work for situations where you only want one chain with a given name to be active at a time. For example, you may only want one sync operation to be active. If there is one pending, you can choose to let it run or replace it with your new work.

The uniqueWorkName uniquely identifies this set of work.

If this method determines that new work should be enqueued and run, all records of previous work with uniqueWorkName will be pruned. If this method determines that new work should NOT be run, then the entire chain will be considered a no-op.

If any work in the chain fails or is cancelled, all of its dependent work inherits that state and will never run. This is particularly important if you are using APPEND as your ExistingWorkPolicy.

Parameters
uniqueWorkName: String

A unique name which for this chain of work

existingWorkPolicy: ExistingWorkPolicy

An ExistingWorkPolicy

work: OneTimeWorkRequest

The OneTimeWorkRequest to enqueue. REPLACE ensures that if there is pending work labelled with uniqueWorkName, it will be cancelled and the new work will run. KEEP will run the new sequence of work only if there is no pending work labelled with uniqueWorkName. APPEND will create a new sequence of work if there is no existing work with uniqueWorkName; otherwise, work will be added as a child of all leaf nodes labelled with uniqueWorkName.

Returns
WorkContinuation

A WorkContinuation that allows further chaining

beginWith

Added in 1.0.0
abstract fun beginWith(work: (Mutable)List<OneTimeWorkRequest!>): WorkContinuation

Begins a chain with one or more OneTimeWorkRequests, which can be enqueued together in the future using enqueue.

If any work in the chain fails or is cancelled, all of its dependent work inherits that state and will never run.

Parameters
work: (Mutable)List<OneTimeWorkRequest!>

One or more OneTimeWorkRequest to start a chain of work

Returns
WorkContinuation

A WorkContinuation that allows for further chaining of dependent OneTimeWorkRequest

beginWith

Added in 1.0.0
fun beginWith(work: OneTimeWorkRequest): WorkContinuation

Begins a chain with one or more OneTimeWorkRequests, which can be enqueued together in the future using enqueue.

If any work in the chain fails or is cancelled, all of its dependent work inherits that state and will never run.

Parameters
work: OneTimeWorkRequest

One or more OneTimeWorkRequest to start a chain of work

Returns
WorkContinuation

A WorkContinuation that allows for further chaining of dependent OneTimeWorkRequest

cancelAllWork

Added in 1.0.0
abstract fun cancelAllWork(): Operation

Cancels all unfinished work. Use this method with extreme caution! By invoking it, you will potentially affect other modules or libraries in your codebase. It is strongly recommended that you use one of the other cancellation methods at your disposal.

Upon cancellation, onStopped will be invoked for any affected workers.

Returns
Operation

An Operation that can be used to determine when the cancelAllWork has completed

cancelAllWorkByTag

Added in 1.0.0
abstract fun cancelAllWorkByTag(tag: String): Operation

Cancels all unfinished work with the given tag. Note that cancellation is a best-effort policy and work that is already executing may continue to run. Upon cancellation, onStopped will be invoked for any affected workers.

Parameters
tag: String

The tag used to identify the work

Returns
Operation

An Operation that can be used to determine when the cancelAllWorkByTag has completed

cancelUniqueWork

Added in 1.0.0
abstract fun cancelUniqueWork(uniqueWorkName: String): Operation

Cancels all unfinished work in the work chain with the given name. Note that cancellation is a best-effort policy and work that is already executing may continue to run. Upon cancellation, onStopped will be invoked for any affected workers.

Parameters
uniqueWorkName: String

The unique name used to identify the chain of work

Returns
Operation

An Operation that can be used to determine when the cancelUniqueWork has completed

cancelWorkById

Added in 1.0.0
abstract fun cancelWorkById(id: UUID): Operation

Cancels work with the given id if it isn't finished. Note that cancellation is a best-effort policy and work that is already executing may continue to run. Upon cancellation, onStopped will be invoked for any affected workers.

Parameters
id: UUID

The id of the work

Returns
Operation

An Operation that can be used to determine when the cancelWorkById has completed

createCancelPendingIntent

Added in 2.3.0
abstract fun createCancelPendingIntent(id: UUID): PendingIntent

Creates a PendingIntent which can be used to cancel a WorkRequest with the given id.

Parameters
id: UUID

The WorkRequest id.

Returns
PendingIntent

The PendingIntent that can be used to cancel the WorkRequest.

enqueue

Added in 1.0.0
abstract fun enqueue(requests: (Mutable)List<WorkRequest!>): Operation

Enqueues one or more items for background processing.

Parameters
requests: (Mutable)List<WorkRequest!>

One or more WorkRequest to enqueue

Returns
Operation

An Operation that can be used to determine when the enqueue has completed

enqueue

Added in 1.0.0
fun enqueue(workRequest: WorkRequest): Operation

Enqueues one item for background processing.

Parameters
workRequest: WorkRequest

The WorkRequest to enqueue

Returns
Operation

An Operation that can be used to determine when the enqueue has completed

enqueueUniquePeriodicWork

Added in 1.0.0
abstract fun enqueueUniquePeriodicWork(
    uniqueWorkName: String,
    existingPeriodicWorkPolicy: ExistingPeriodicWorkPolicy,
    periodicWork: PeriodicWorkRequest
): Operation

This method allows you to enqueue a uniquely-named PeriodicWorkRequest, where only one PeriodicWorkRequest of a particular name can be active at a time. For example, you may only want one sync operation to be active. If there is one pending, you can choose to let it run or replace it with your new work.

The uniqueWorkName uniquely identifies this PeriodicWorkRequest.

Parameters
uniqueWorkName: String

A unique name which for this operation

existingPeriodicWorkPolicy: ExistingPeriodicWorkPolicy

An ExistingPeriodicWorkPolicy

periodicWork: PeriodicWorkRequest

A PeriodicWorkRequest to enqueue. REPLACE ensures that if there is pending work labelled with uniqueWorkName, it will be cancelled and the new work will run. KEEP will run the new PeriodicWorkRequest only if there is no pending work labelled with uniqueWorkName.

Returns
Operation

An Operation that can be used to determine when the enqueue has completed

enqueueUniqueWork

Added in 1.0.0
abstract fun enqueueUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: (Mutable)List<OneTimeWorkRequest!>
): Operation

This method allows you to enqueue work requests to a uniquely-named WorkContinuation, where only one continuation of a particular name can be active at a time. For example, you may only want one sync operation to be active. If there is one pending, you can choose to let it run or replace it with your new work.

The uniqueWorkName uniquely identifies this WorkContinuation.

Parameters
uniqueWorkName: String

A unique name which for this operation

existingWorkPolicy: ExistingWorkPolicy

An ExistingWorkPolicy

work: (Mutable)List<OneTimeWorkRequest!>

OneTimeWorkRequests to enqueue. REPLACE ensures that if there is pending work labelled with uniqueWorkName, it will be cancelled and the new work will run. KEEP will run the new OneTimeWorkRequests only if there is no pending work labelled with uniqueWorkName. APPEND will append the OneTimeWorkRequests as leaf nodes labelled with uniqueWorkName.

Returns
Operation

An Operation that can be used to determine when the enqueue has completed

enqueueUniqueWork

Added in 1.0.0
fun enqueueUniqueWork(
    uniqueWorkName: String,
    existingWorkPolicy: ExistingWorkPolicy,
    work: OneTimeWorkRequest
): Operation

This method allows you to enqueue work requests to a uniquely-named WorkContinuation, where only one continuation of a particular name can be active at a time. For example, you may only want one sync operation to be active. If there is one pending, you can choose to let it run or replace it with your new work.

The uniqueWorkName uniquely identifies this WorkContinuation.

Parameters
uniqueWorkName: String

A unique name which for this operation

existingWorkPolicy: ExistingWorkPolicy

An ExistingWorkPolicy; see below for more information

work: OneTimeWorkRequest

The OneTimeWorkRequests to enqueue. REPLACE ensures that if there is pending work labelled with uniqueWorkName, it will be cancelled and the new work will run. KEEP will run the new OneTimeWorkRequests only if there is no pending work labelled with uniqueWorkName. APPEND will append the OneTimeWorkRequests as leaf nodes labelled with uniqueWorkName.

Returns
Operation

An Operation that can be used to determine when the enqueue has completed

getConfiguration

Added in 2.8.0
abstract fun getConfiguration(): Configuration

Provides the Configuration instance that WorkManager was initialized with.

Returns
Configuration

The Configuration instance that WorkManager was initialized with.

getInstance

Added in 1.0.0
Deprecated in 2.1.0
java-static fun getInstance(): WorkManager

Retrieves the default singleton instance of WorkManager.

Returns
WorkManager

The singleton instance of WorkManager; this may be null in unusual circumstances where you have disabled automatic initialization and have failed to manually call initialize.

Throws
java.lang.IllegalStateException

If WorkManager is not initialized properly as per the exception message.

getInstance

Added in 2.1.0
java-static fun getInstance(context: Context): WorkManager

Retrieves the default singleton instance of WorkManager.

Parameters
context: Context

A Context for on-demand initialization.

Returns
WorkManager

The singleton instance of WorkManager; this may be null in unusual circumstances where you have disabled automatic initialization and have failed to manually call initialize.

Throws
java.lang.IllegalStateException

If WorkManager is not initialized properly

getLastCancelAllTimeMillis

Added in 1.0.0
abstract fun getLastCancelAllTimeMillis(): ListenableFuture<Long!>

Gets a ListenableFuture of the last time all work was cancelled. This method is intended for use by library and module developers who have dependent data in their own repository that must be updated or deleted in case someone cancels their work without their prior knowledge.

Returns
ListenableFuture<Long!>

A ListenableFuture of the timestamp (System#getCurrentTimeMillis()) when cancelAllWork was last invoked; this timestamp may be 0L if this never occurred

getLastCancelAllTimeMillisLiveData

Added in 1.0.0
abstract fun getLastCancelAllTimeMillisLiveData(): LiveData<Long!>

Gets a LiveData of the last time all work was cancelled. This method is intended for use by library and module developers who have dependent data in their own repository that must be updated or deleted in case someone cancels their work without their prior knowledge.

Returns
LiveData<Long!>

A LiveData of the timestamp (System#getCurrentTimeMillis()) when cancelAllWork was last invoked; this timestamp may be 0L if this never occurred

getWorkInfoById

Added in 1.0.0
abstract fun getWorkInfoById(id: UUID): ListenableFuture<WorkInfo!>

Gets a ListenableFuture of the WorkInfo for a given work id.

Parameters
id: UUID

The id of the work

Returns
ListenableFuture<WorkInfo!>

A ListenableFuture of the WorkInfo associated with id; note that this WorkInfo may be null if id is not known to WorkManager

getWorkInfoByIdFlow

Added in 2.9.0
abstract fun getWorkInfoByIdFlow(id: UUID): Flow<WorkInfo!>

Gets a Flow of the WorkInfo for a given work id.

Parameters
id: UUID

The id of the work

Returns
Flow<WorkInfo!>

A Flow of the WorkInfo associated with id; note that this WorkInfo may be null if id is not known to WorkManager.

getWorkInfoByIdLiveData

Added in 1.0.0
abstract fun getWorkInfoByIdLiveData(id: UUID): LiveData<WorkInfo!>

Gets a LiveData of the WorkInfo for a given work id.

Parameters
id: UUID

The id of the work

Returns
LiveData<WorkInfo!>

A LiveData of the WorkInfo associated with id; note that this WorkInfo may be null if id is not known to WorkManager.

getWorkInfos

Added in 2.4.0
abstract fun getWorkInfos(workQuery: WorkQuery): ListenableFuture<(Mutable)List<WorkInfo!>!>

Gets the ListenableFuture of the List of WorkInfo for all work referenced by the WorkQuery specification.

Parameters
workQuery: WorkQuery

The work query specification

Returns
ListenableFuture<(Mutable)List<WorkInfo!>!>

A ListenableFuture of the List of WorkInfo for work referenced by this WorkQuery.

getWorkInfosByTag

Added in 1.0.0
abstract fun getWorkInfosByTag(tag: String): ListenableFuture<(Mutable)List<WorkInfo!>!>

Gets a ListenableFuture of the WorkInfo for all work for a given tag.

Parameters
tag: String

The tag of the work

Returns
ListenableFuture<(Mutable)List<WorkInfo!>!>

A ListenableFuture list of WorkInfo for work tagged with tag

getWorkInfosByTagFlow

Added in 2.9.0
abstract fun getWorkInfosByTagFlow(tag: String): Flow<(Mutable)List<WorkInfo!>!>

Gets a Flow of the WorkInfo for all work for a given tag.

Parameters
tag: String

The tag of the work

Returns
Flow<(Mutable)List<WorkInfo!>!>

A Flow list of WorkInfo for work tagged with tag

getWorkInfosByTagLiveData

Added in 1.0.0
abstract fun getWorkInfosByTagLiveData(tag: String): LiveData<(Mutable)List<WorkInfo!>!>

Gets a LiveData of the WorkInfo for all work for a given tag.

Parameters
tag: String

The tag of the work

Returns
LiveData<(Mutable)List<WorkInfo!>!>

A LiveData list of WorkInfo for work tagged with tag

getWorkInfosFlow

Added in 2.9.0
abstract fun getWorkInfosFlow(workQuery: WorkQuery): Flow<(Mutable)List<WorkInfo!>!>

Gets the Flow of the List of WorkInfo for all work referenced by the WorkQuery specification.

Parameters
workQuery: WorkQuery

The work query specification

Returns
Flow<(Mutable)List<WorkInfo!>!>

A Flow of the List of WorkInfo for work referenced by this WorkQuery.

getWorkInfosForUniqueWork

Added in 1.0.0
abstract fun getWorkInfosForUniqueWork(uniqueWorkName: String): ListenableFuture<(Mutable)List<WorkInfo!>!>

Gets a ListenableFuture of the WorkInfo for all work in a work chain with a given unique name.

Parameters
uniqueWorkName: String

The unique name used to identify the chain of work

Returns
ListenableFuture<(Mutable)List<WorkInfo!>!>

A ListenableFuture of the WorkInfo for work in the chain named uniqueWorkName

getWorkInfosForUniqueWorkFlow

Added in 2.9.0
abstract fun getWorkInfosForUniqueWorkFlow(uniqueWorkName: String): Flow<(Mutable)List<WorkInfo!>!>

Gets a Flow of the WorkInfo for all work in a work chain with a given unique name.

Parameters
uniqueWorkName: String

The unique name used to identify the chain of work

Returns
Flow<(Mutable)List<WorkInfo!>!>

A Flow of the WorkInfo for work in the chain named uniqueWorkName

getWorkInfosForUniqueWorkLiveData

Added in 1.0.0
abstract fun getWorkInfosForUniqueWorkLiveData(uniqueWorkName: String): LiveData<(Mutable)List<WorkInfo!>!>

Gets a LiveData of the WorkInfo for all work in a work chain with a given unique name.

Parameters
uniqueWorkName: String

The unique name used to identify the chain of work

Returns
LiveData<(Mutable)List<WorkInfo!>!>

A LiveData of the WorkInfo for work in the chain named uniqueWorkName

getWorkInfosLiveData

Added in 2.4.0
abstract fun getWorkInfosLiveData(workQuery: WorkQuery): LiveData<(Mutable)List<WorkInfo!>!>

Gets the LiveData of the List of WorkInfo for all work referenced by the WorkQuery specification.

Parameters
workQuery: WorkQuery

The work query specification

Returns
LiveData<(Mutable)List<WorkInfo!>!>

A LiveData of the List of WorkInfo for work referenced by this WorkQuery.

initialize

Added in 1.0.0
java-static fun initialize(context: Context, configuration: Configuration): Unit

Used to do a one-time initialization of the WorkManager singleton with a custom Configuration. By default, this method should not be called because WorkManager is automatically initialized. To initialize WorkManager yourself, please follow these steps:

  • Disable androidx.work.WorkManagerInitializer in your manifest.
  • Invoke this method in Application#onCreate or a ContentProvider. Note that this method must be invoked in one of these two places or you risk getting a NullPointerException in getInstance.

This method throws an IllegalStateException when attempting to initialize in direct boot mode.

This method throws an exception if it is called multiple times.

Parameters
context: Context

A Context object for configuration purposes. Internally, this class will call getApplicationContext, so you may safely pass in any Context without risking a memory leak.

configuration: Configuration

The Configuration for used to set up WorkManager.

See also
Configuration.Provider

for on-demand initialization.

isInitialized

Added in 2.8.0
java-static fun isInitialized(): Boolean

Provides a way to check if WorkManager is initialized in this process.

Returns
Boolean

true if WorkManager has been initialized in this process.

pruneWork

Added in 1.0.0
abstract fun pruneWork(): Operation

Prunes all eligible finished work from the internal database. Eligible work must be finished (SUCCEEDED, FAILED, or CANCELLED), with zero unfinished dependents.

Use this method with caution; by invoking it, you (and any modules and libraries in your codebase) will no longer be able to observe the WorkInfo of the pruned work. You do not normally need to call this method - WorkManager takes care to auto-prune its work after a sane period of time. This method also ignores the keepResultsForAtLeast policy.

Returns
Operation

An Operation that can be used to determine when the pruneWork has completed

updateWork

Added in 2.8.0
abstract fun updateWork(request: WorkRequest): ListenableFuture<WorkManager.UpdateResult!>

Updates the work with the new specification. A WorkRequest passed as parameter must have an id set with setId that matches an id of the previously enqueued work.

It preserves enqueue time, e.g. if a work was enqueued 3 hours ago and had 6 hours long initial delay, after the update it would be still eligible for run in 3 hours, assuming that initial delay wasn't updated.

If the work being updated is currently running the returned ListenableFuture will be completed with APPLIED_FOR_NEXT_RUN. In this case the current run won't be interrupted and will continue to rely on previous state of the request, e.g. using old constraints, tags etc. However, on the next run, e.g. retry of one-time Worker or another iteration of periodic worker, the new worker specification will be used.

If the one time work that is updated is already finished the returned ListenableFuture will be completed with NOT_APPLIED.

If update can be applied immediately, e.g. the updated work isn't currently running, the returned ListenableFuture will be completed with APPLIED_IMMEDIATELY.

If the work with the given id (request.getId()) doesn't exist the returned ListenableFuture will be completed exceptionally with IllegalArgumentException.

Worker type can't be changed, OneTimeWorkRequest can't be updated to PeriodicWorkRequest and otherwise, the returned ListenableFuture will be completed with IllegalArgumentException.

Parameters
request: WorkRequest

the new specification for the work.

Returns
ListenableFuture<WorkManager.UpdateResult!>

a ListenableFuture that will be successfully completed if the update was successful. The future will be completed with an exception if the work is already running or finished.