我已经关注this关于如何在WorkManager上进行DI的文章，所以我有这个工厂：
class MyWorkerFactory @Inject constructor(
val workerFactories: Map<Class<out ListenableWorker>, @JvmSuppressWildcards Provider<ChildWorkerFactory>>
) : WorkerFactory() {
override fun createWorker(
appContext: Context,
workerClassName: String,
workerParameters: WorkerParameters
): ListenableWorker? {
val foundEntry = workerFactories.entries.find { Class.forName(workerClassName).isAssignableFrom(it.key) }
return if (foundEntry != null) {
val factoryProvider = foundEntry.value
factoryProvider.get().create(appContext, workerParameters)
} else {
val workerClass = Class.forName(workerClassName).asSubclass(ListenableWorker::class.java)
val constructor = workerClass.getDeclaredConstructor(Context::class.java, WorkerParameters::class.java)
constructor.newInstance(appContext, workerParameters)
}
}
}
这是我的模块：
@Retention(AnnotationRetention.RUNTIME)
@MapKey
annotation class WorkerKey(val value: KClass<out ListenableWorker>)
@Module
abstract class ParcelPollModule {
@Binds
@IntoMap
@WorkerKey(ParcelPollWorker::class)
internal abstract fun bindMyWorkerFactory(worker: ParcelPollWorker.Factory): ChildWorkerFactory
}
这是我的应用程序组件的一部分。然后在我的Application类上执行此操作：
@Inject lateinit var myWorkerFactory: MyWorkerFactory
private fun setupWorkerFactory() {
WorkManager.initialize(
this,
Configuration.Builder()
.setWorkerFactory(myWorkerFactory)
.build()
)
}
我的工人班：
class ParcelPollWorker constructor(val parcelRepository: LocalParcelRepository,
val correosRepository: CorreosRepository,
appContext: Context, workerParams: WorkerParameters) : RxWorker(appContext, workerParams) {
override fun createWork(): Single<Result> {
Timber.w("Parcel poll worker $this here trying to do some work!")
return parcelRepository.getParcels()
.flatMapIterable {
it
}
.map {
Timber.d("Parcel poll checking parcel with code ${it.code}")
// correosRepository.getParcelStatus(it.code)
}
.toList()
.map { Result.success() }
.onErrorReturn {
Result.failure()
}
}
class Factory @Inject constructor(
val myRepository: LocalParcelRepository,
val networkService: CorreosRepository
) : ChildWorkerFactory {
override fun create(appContext: Context, params: WorkerParameters): ListenableWorker {
return ParcelPollWorker(myRepository, networkService, appContext, params)
}
}
}
现在，即使我没有安排这个工人全部，我的日志也会多次打印具有不同实例的Parcel poll worker $this here trying to do some work!（有时是3，有时是6）！在启动应用程序时，实际工作中的行也会多次打印：
2020-01-08 08:37:40.892 7011-7011/com.myapp.android W/ParcelPollWorker: Parcel poll worker com.myapp.service.worker.ParcelPollWorker@c1f5d23 here trying to do some work!
2020-01-08 08:37:40.923 7011-7011/com.myapp.android W/ParcelPollWorker: Parcel poll worker com.myapp.service.worker.ParcelPollWorker@c80a87f here trying to do some work!
2020-01-08 08:37:40.924 7011-7011/com.myapp.android W/ParcelPollWorker: Parcel poll worker com.myapp.service.worker.ParcelPollWorker@85b9895 here trying to do some work!
2020-01-08 08:37:40.945 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583511008898301184149
2020-01-08 08:37:40.946 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 800692129
2020-01-08 08:37:40.946 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code PQ5HG70200028570115706M
2020-01-08 08:37:40.946 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code UX6CFH0459568380108027M
2020-01-08 08:37:40.947 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 6307253297994985
2020-01-08 08:37:40.949 7011-7113/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583560022440001250051
2020-01-08 08:37:40.954 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583511008898301184149
2020-01-08 08:37:40.955 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 800692129
2020-01-08 08:37:40.955 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code PQ5HG70200028570115706M
2020-01-08 08:37:40.955 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583511008898301184149
2020-01-08 08:37:40.955 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 800692129
2020-01-08 08:37:40.955 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code UX6CFH0459568380108027M
2020-01-08 08:37:40.955 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code PQ5HG70200028570115706M
2020-01-08 08:37:40.956 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code UX6CFH0459568380108027M
2020-01-08 08:37:40.956 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 6307253297994985
2020-01-08 08:37:40.956 7011-7102/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583560022440001250051
2020-01-08 08:37:40.956 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 6307253297994985
2020-01-08 08:37:40.956 7011-7101/com.myapp.android D/ParcelPollWorker$createWork: Parcel poll checking parcel with code 63583560022440001250051
这怎么可能？我检查了RxWorker的实现，并且它不应至少打印工作本身，直到它开始（即有人订阅了它）]
public RxWorker(@NonNull Context appContext, @NonNull WorkerParameters workerParams) {
super(appContext, workerParams);
}
@NonNull
@Override
public ListenableFuture<Result> startWork() {
mSingleFutureObserverAdapter = new SingleFutureAdapter<>();
final Scheduler scheduler = getBackgroundScheduler();
createWork()
.subscribeOn(scheduler)
// observe on WM's private thread
.observeOn(Schedulers.from(getTaskExecutor().getBackgroundExecutor()))
.subscribe(mSingleFutureObserverAdapter);
return mSingleFutureObserverAdapter.mFuture;
}
我在这里迷失了可能发生的事情。代码是开源的，可以检查here
持有工人的班级：
class ParcelListActivity : BaseActivity() {
@Inject
lateinit var myWorkerFactory: MyWorkerFactory
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setSupportActionBar(toolbar)
supportActionBar?.setDisplayShowTitleEnabled(true)
fab.setOnClickListener {
startActivityForResult(CreateActivity.newIntent(this),
REQ_CREATE_PARCEL)
}
val constraints = Constraints.Builder()
.setRequiredNetworkType(NetworkType.CONNECTED)
.build()
val uploadWorker = PeriodicWorkRequest.Builder(
ParcelPollWorker::class.java, 15, TimeUnit.MINUTES)
.setConstraints(constraints)
.build()
WorkManager.getInstance(this).enqueue(uploadWorker)
}
...
}
[@ art建议后的更改：
private fun initWorker() {
val constraints = Constraints.Builder()
.setRequiredNetworkType(NetworkType.CONNECTED)
.build()
val uploadWorker = PeriodicWorkRequest.Builder(
ParcelPollWorker::class.java, 15, TimeUnit.MINUTES)
.setConstraints(constraints)
.build()
WorkManager.getInstance(this).cancelAllWork()
WorkManager.getInstance(this).enqueueUniquePeriodicWork(PARCEL_CHECKER_WORKREQUEST, ExistingPeriodicWorkPolicy.REPLACE, uploadWorker)
}
1。请注意，根据RxWorker的源代码：
@NonNull
@Override
public ListenableFuture<Result> startWork() {
mSingleFutureObserverAdapter = new SingleFutureAdapter<>();
final Scheduler scheduler = getBackgroundScheduler();
createWork()
.subscribeOn(scheduler)
// observe on WM's private thread
.observeOn(Schedulers.from(getTaskExecutor().getBackgroundExecutor()))
.subscribe(mSingleFutureObserverAdapter);
return mSingleFutureObserverAdapter.mFuture;
}
工作的执行在调用subscribe对象的Single方法的那一刻开始。因此您的陈述不正确：
这怎么可能？我检查了RxWorker的实现，并且它不应至少打印工作本身，直到它开始（即有人订阅了它）]
[2。大概在开发过程中的某个时候，您在ParcelListActivity.onCreate方法中使工作程序入队，并且您多次打开了此活动，因此使周期性工作程序入队了几次，WorkManager将该工作坚持到了内部数据库，然后根据您的优先请求配置启动工作。
要解决此问题，您可以使用cancelAllWork方法。但正如文档声称您使用此方法时，应格外小心！通常，定期工作需要更精确的处理。例如，您可以将assign a tag用于您的工作请求，然后可以使用cancelAllWorkByTag方法来取消工作。此外，您可以考虑launch your work as unique-对于大多数情况，它是更合适的方法。