RxRemoteMediator

Artifact: androidx.paging:paging-rxjava3

View Source

Added in 3.0.0

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Kotlin |Java

@ExperimentalPagingApi
abstract class RxRemoteMediator<Key : Any, Value : Any> : RemoteMediator

kotlin.Any
↳	androidx.paging.RemoteMediator
	↳	androidx.paging.rxjava3.RxRemoteMediator

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RxJava3 compatibility wrapper around RemoteMediator's suspending APIs.

Summary

Public constructors
<Key : Any, Value : Any> RxRemoteMediator()

Public functions
final suspend RemoteMediator.InitializeAction	initialize()
open Single<RemoteMediator.InitializeAction>	initializeSingle() Callback fired during initialization of a PagingData stream, before initial load.
final suspend RemoteMediator.MediatorResult	load(loadType: LoadType, state: PagingState<Key, Value>)
abstract Single<RemoteMediator.MediatorResult>	loadSingle(loadType: LoadType, state: PagingState<Key, Value>) Implement this method to load additional remote data, which will then be stored for the PagingSource to access.

Public constructors

RxRemoteMediator

<Key : Any, Value : Any> RxRemoteMediator()

Public functions

initialize

final suspend fun initialize(): RemoteMediator.InitializeAction

initializeSingle

Added in 3.0.0

open fun initializeSingle(): Single<RemoteMediator.InitializeAction>

Callback fired during initialization of a PagingData stream, before initial load.

This function runs to completion before any loading is performed.

Returns

Single<RemoteMediator.InitializeAction>

InitializeAction indicating the action to take after initialization: LAUNCH_INITIAL_REFRESH to immediately dispatch a load asynchronously with load type LoadType.REFRESH, to update paginated content when the stream is initialized. Note: This also prevents RemoteMediator from triggering PREPEND or APPEND until REFRESH succeeds. InitializeAction.SKIP_INITIAL_REFRESH to wait for a refresh request from the UI before dispatching a load with load type LoadType.REFRESH.

load

final suspend fun load(loadType: LoadType, state: PagingState<Key, Value>): RemoteMediator.MediatorResult

loadSingle

Added in 3.0.0

abstract fun loadSingle(loadType: LoadType, state: PagingState<Key, Value>): Single<RemoteMediator.MediatorResult>

Implement this method to load additional remote data, which will then be stored for the PagingSource to access. These loads take one of two forms:

• type == LoadType.PREPEND / LoadType.APPEND The PagingSource has loaded a 'boundary' page, with a null adjacent key. This means this method should load additional remote data to append / prepend as appropriate, and store it locally.

• type == LoadType.REFRESH The app (or initialize) has requested a remote refresh of data. This means the method should generally load remote data, and replace all local data.

The runtime of this method defines loading state behavior in boundary conditions, which affects e.g., LoadState callbacks registered to androidx.paging.PagingDataAdapter.

NOTE: A PagingSource.load request which is fulfilled by a page that hits a boundary condition in either direction will trigger this callback with LoadType.PREPEND or LoadType.APPEND or both. LoadType.REFRESH occurs as a result of initialize.

Parameters
loadType: LoadType	LoadType of the boundary condition which triggered this callback. LoadType.PREPEND indicates a boundary condition at the front of the list. LoadType.APPEND indicates a boundary condition at the end of the list. LoadType.REFRESH indicates this callback was triggered as the result of a requested refresh - either driven by the UI, or by initialize.
state: PagingState<Key, Value>	A copy of the state including the list of pages currently held in memory of the currently presented PagingData at the time of starting the load. E.g. for load(loadType = END), you can use the page or item at the end as input for what to load from the network.

Returns
Single<RemoteMediator.MediatorResult>	MediatorResult signifying what LoadState to be passed to the UI, and whether there's more data available.