A library that adds additional Kotlin/Multiplatform targets to AndroidX Paging, and provides UI components to use Paging on iOS.
As with AndroidX Paging, the primary modules of Multiplatform Paging are:
paging-common– encompasses the repository layer and the view model layerpaging-runtime– encompasses the UI layer
Unlike AndroidX Paging that has a limited number of targets for paging-common and makes paging-runtime Android-specific,
Multiplatform Paging adds many more targets to paging-common and provides paging-runtime-uikit, a UIKit-specific runtime for iOS.
Therefore, pagination logic between many more targets can be shared,
and the provided UI components can be used to render the paged items on Android and iOS.
For a holistic view of Multiplatform Paging, check out the GitHub Repository Search sample project, where there's an Android, Desktop, and iOS app, along with shared pagination logic.
The API of paging-common in Multiplatform Paging is identical to that of paging-common in AndroidX Paging
(with the exception that: the namespace has changed from androidx.paging to app.cash.paging;
there are some minor API discrepancies due to limitations in the Kotlin compiler).
Therefore, to see how to use paging-common, consult the official documentation of AndroidX Paging.
Like AndroidX Paging, all targets except for the JVM include the Paging 3 APIs only from AndroidX Paging. There are no plans to add support for Paging 2 APIs beyond the JVM.
app.cash.paging:paging-common on these targets delegate to androidx.paging:paging-common via type aliases.
To understand what this means in practice, see the section Interoperability with AndroidX Paging.
app.cash.paging:paging-common on these targets delegate to our fork of AndroidX Paging.
The API of paging-compose-common in Multiplatform Paging is identical to that of paging-compose in AndroidX Paging
(with the exception that the namespace has changed from androidx.paging to app.cash.paging).
To see how to use paging-compose-common, consult the official documentation of AndroidX Paging.
app.cash.paging:paging-compose-common on Android delegates to androidx.paging:paging-compose via type aliases.
To understand what this means in practice, see the section Interoperability with AndroidX Paging.
app.cash.paging:paging-compose-common on the these targets delegate to our fork of AndroidX Paging.
See the Interoperability with AndroidX Paging section below.
The PagingCollectionViewController allows a PagingData to be rendered via a UICollectionView.
The PagingCollectionViewController mimics the UICollectionViewController,
providing: the cell count; and item retrieval via IndexPath.
Here's an example in Swift:
final class FooViewController: UICollectionViewController {
private let delegate = Paging_runtime_uikitPagingCollectionViewController<Foo>()
private let presenter = …
required init(coder: NSCoder) {
super.init(coder: coder)!
presenter.pagingDatas
.sink { pagingData in
self.delegate.submitData(pagingData: pagingData, completionHandler: …)
}
}
override func collectionView(
_ collectionView: UICollectionView,
numberOfItemsInSection section: Int
) -> Int {
return Int(delegate.collectionView(collectionView: collectionView, numberOfItemsInSection: Int64(section)))
}
override func collectionView(
_ collectionView: UICollectionView,
cellForItemAt indexPath: IndexPath
) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "FooCell", for: indexPath) as! FooCell
let item = delegate.getItem(position: Int32(indexPath.row))!
// …
return cell
}
}The API of paging-testing in Multiplatform Paging is identical to that of paging-testing in AndroidX Paging
(with the exception that the namespace has changed from androidx.paging to app.cash.paging).
Therefore, to see how to use paging-testing, consult the official documentation of AndroidX Paging.
app.cash.paging:paging-testing on these targets delegate to androidx.paging:paging-testing via type aliases.
To understand what this means in practice, see the section Interoperability with AndroidX Paging.
app.cash.paging:paging-common on these targets delegate to our fork of AndroidX Paging.
As app.cash.paging:paging-common on the JVM, iOS, Linux X64, and macOS type alias to androidx.paging:paging-common,
some useful side effects occur:
- The implementation of
app.cash.paging:paging-commonon the JVM, iOS, Linux X64, and macOS is identical toandroidx.paging:paging-common. This means that it is impossible for there to be a behavioral discrepancy when usingapp.cash.paging:paging-commonon the JVM, iOS, Linux X64, or macOS. - All libraries that depend on
androidx.paging:paging-commoncan continue to be used. Some JVM-specific examples includeandroidx.paging:paging-runtime,androidx.paging:paging-compose, andandroidx.paging:paging-rxjava3. This is why there aren't additionalpaging-runtimeartifacts to support Android's UI toolkit, as you can instead depend on the official AndroidX artifact. - If you're already using AndroidX Paging, you don't need to refactor your existing codebase to begin using Multiplatform Paging.
The use of Multiplatform Paging is only necessary if you wish to share pagination logic on targets that AndroidX Paging don't yet support, or you want to use pagination UI bindings on platforms like iOS via
paging-runtime-uikit.
A similar argument can be made for app.cash.paging:paging-compose-common and app.cash.paging:paging-testing.
The versioning scheme is of the form X-Y where:
Xis the AndroidX Paging version that is being tracked.Yis the Multiplatform Paging version.
For example, if AndroidX Paging is on 3.3.0-alpha02 and Multiplatform Paging is on 0.5.1,
the artifact for a release of paging-common will be app.cash.paging:paging-common:3.3.0-alpha02-0.5.1.
implementation("app.cash.paging:paging-common:3.3.0-alpha02-0.5.1")implementation("app.cash.paging:paging-compose-common:3.3.0-alpha02-0.5.1")implementation("app.cash.paging:paging-runtime-uikit:3.3.0-alpha02-0.5.1")implementation("app.cash.paging:paging-testing:3.3.0-alpha02-0.5.1")Use the official AndroidX Paging dependencies.
implementation("androidx.paging:paging-runtime:3.3.0-alpha02")
implementation("androidx.paging:paging-compose:3.3.0-alpha02")
implementation("androidx.paging:paging-rxjava3:3.3.0-alpha02")
// etc.Copyright 2022 Block, Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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