Files
CoreStore/Sources/DiffableDataSource.TableView-UIKit.swift
John Estropia 145edd5a7d README update
2019-10-21 21:15:46 +09:00

373 lines
14 KiB
Swift

//
// DiffableDataSource.TableView-UIKit.swift
// CoreStore
//
// Copyright © 2018 John Rommel Estropia
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
#if canImport(UIKit) && (os(iOS) || os(tvOS))
import UIKit
import CoreData
// MARK: - DiffableDataSource
extension DiffableDataSource {
// MARK: - TableView
/**
The `DiffableDataSource.TableView` serves as a `UITableViewDataSource` that handles `ListPublisher` snapshots for a `UITableView`. Subclasses of `DiffableDataSource.TableView` may override some `UITableViewDataSource` methods as needed.
The `DiffableDataSource.TableView` instance needs to be held on (retained) for as long as the `UITableView`'s lifecycle.
```
self.dataSource = DiffableDataSource.TableView<Person>(
tableView: self.tableView,
dataStack: CoreStoreDefaults.dataStack,
cellProvider: { (tableView, indexPath, person) in
let cell = tableView.dequeueReusableCell(withIdentifier: "PersonCell") as! PersonCell
cell.setPerson(person)
return cell
}
)
```
The dataSource can then apply changes from a `ListPublisher` as shown:
```
listPublisher.addObserver(self) { [weak self] (listPublisher) in
self?.dataSource?.apply(
listPublisher.snapshot,
animatingDifferences: true
)
}
```
`DiffableDataSource.TableView` fully handles the reload animations. To turn change the default animation, set the `defaultRowAnimation`.
- SeeAlso: CoreStore's DiffableDataSource implementation is based on https://github.com/ra1028/DiffableDataSources
*/
open class TableView<O: DynamicObject>: NSObject, UITableViewDataSource {
// MARK: Open
/**
The animation style for row changes
*/
@nonobjc
open var defaultRowAnimation: UITableView.RowAnimation = .automatic
// MARK: Public
/**
The object type represented by this dataSource
*/
public typealias ObjectType = O
/**
Initializes the `DiffableDataSource.TableView`. This instance needs to be held on (retained) for as long as the `UITableView`'s lifecycle.
```
self.dataSource = DiffableDataSource.TableView<Person>(
tableView: self.tableView,
dataStack: CoreStoreDefaults.dataStack,
cellProvider: { (tableView, indexPath, person) in
let cell = tableView.dequeueReusableCell(withIdentifier: "PersonCell") as! PersonCell
cell.setPerson(person)
return cell
}
)
```
- parameter tableView: the `UITableView` to set the `dataSource` of. This instance is not retained by the `DiffableDataSource.TableView`.
- parameter dataStack: the `DataStack` instance that the dataSource will fetch objects from
- parameter cellProvider: a closure that configures and returns the `UITableViewCell` for the object
*/
@nonobjc
public init(tableView: UITableView, dataStack: DataStack, cellProvider: @escaping (UITableView, IndexPath, O) -> UITableViewCell?) {
self.tableView = tableView
self.cellProvider = cellProvider
self.dataStack = dataStack
self.dispatcher = Internals.DiffableDataUIDispatcher<O>(dataStack: dataStack)
super.init()
tableView.dataSource = self
}
/**
Reloads the `UITableView` using a `ListSnapshot`. This is typically from the `snapshot` property of a `ListPublisher`:
```
listPublisher.addObserver(self) { [weak self] (listPublisher) in
self?.dataSource?.apply(
listPublisher.snapshot,
animatingDifferences: true
)
}
```
If the `defaultRowAnimation` is configured to, animations are also applied accordingly.
- parameter snapshot: the `ListSnapshot` used to reload the `UITableView` with. This is typically from the `snapshot` property of a `ListPublisher`.
- parameter animatingDifferences: if `true`, animations will be applied as configured by the `defaultRowAnimation` value. Defaults to `true`.
*/
@nonobjc
public func apply(_ snapshot: ListSnapshot<O>, animatingDifferences: Bool = true) {
let diffableSnapshot = snapshot.diffableSnapshot
// if #available(iOS 13.0, tvOS 13.0, watchOS 6.0, macOS 10.15, *) {
//
// self.modernDataSource.apply(
// diffableSnapshot as! NSDiffableDataSourceSnapshot<String, NSManagedObjectID>,
// animatingDifferences: animatingDifferences,
// completion: nil
// )
// }
// else {
self.dispatcher.apply(
diffableSnapshot as! Internals.DiffableDataSourceSnapshot,
view: self.tableView,
animatingDifferences: animatingDifferences,
performUpdates: { tableView, changeset, setSections in
tableView.reload(
using: changeset,
with: self.defaultRowAnimation,
setData: setSections
)
}
)
// }
}
/**
Returns the object identifier for the item at the specified `IndexPath`, or `nil` if not found
- parameter indexPath: the `IndexPath` to search for
- returns: the object identifier for the item at the specified `IndexPath`, or `nil` if not found
*/
@nonobjc
public func itemID(for indexPath: IndexPath) -> O.ObjectID? {
return self.dispatcher.itemIdentifier(for: indexPath)
}
/**
Returns the `IndexPath` for the item with the specified object identifier, or `nil` if not found
- parameter itemID: the object identifier to search for
- returns: the `IndexPath` for the item with the specified object identifier, or `nil` if not found
*/
@nonobjc
public func indexPath(for itemID: O.ObjectID) -> IndexPath? {
return self.dispatcher.indexPath(for: itemID)
}
// MARK: - UITableViewDataSource
@objc
public dynamic func numberOfSections(in tableView: UITableView) -> Int {
return self.dispatcher.numberOfSections()
}
@objc
public dynamic func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.dispatcher.numberOfItems(inSection: section)
}
@objc
open dynamic func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
return self.dispatcher.sectionIdentifier(inSection: section)
}
@objc
open dynamic func tableView(_ tableView: UITableView, titleForFooterInSection section: Int) -> String? {
return nil
}
@objc
open dynamic func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let objectID = self.dispatcher.itemIdentifier(for: indexPath) else {
Internals.abort("Object at \(Internals.typeName(IndexPath.self)) \(indexPath) already removed from list")
}
guard let object = self.dataStack.fetchExisting(objectID) as O? else {
Internals.abort("Object at \(Internals.typeName(IndexPath.self)) \(indexPath) has been deleted")
}
guard let cell = self.cellProvider(tableView, indexPath, object) else {
Internals.abort("\(Internals.typeName(UITableViewDataSource.self)) returned a `nil` cell for \(Internals.typeName(IndexPath.self)) \(indexPath)")
}
return cell
}
@objc
open dynamic func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
@objc
open dynamic func tableView(_ tableView: UITableView, editingStyleForRowAt indexPath: IndexPath) -> UITableViewCell.EditingStyle {
return .delete
}
@objc
open dynamic func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {}
// MARK: Private
@nonobjc
private weak var tableView: UITableView?
@nonobjc
private let dataStack: DataStack
@nonobjc
private let cellProvider: (UITableView, IndexPath, O) -> UITableViewCell?
@nonobjc
private let dispatcher: Internals.DiffableDataUIDispatcher<O>
}
}
// MARK: - UITableView
extension UITableView {
// MARK: FilePrivate
// Implementation based on https://github.com/ra1028/DiffableDataSources
@nonobjc
fileprivate func reload<C, O>(
using stagedChangeset: Internals.DiffableDataUIDispatcher<O>.StagedChangeset<C>,
with animation: @autoclosure () -> RowAnimation,
interrupt: ((Internals.DiffableDataUIDispatcher<O>.Changeset<C>) -> Bool)? = nil,
setData: (C) -> Void
) {
self.reload(
using: stagedChangeset,
deleteSectionsAnimation: animation(),
insertSectionsAnimation: animation(),
reloadSectionsAnimation: animation(),
deleteRowsAnimation: animation(),
insertRowsAnimation: animation(),
reloadRowsAnimation: animation(),
interrupt: interrupt,
setData: setData
)
}
// Implementation based on https://github.com/ra1028/DiffableDataSources
@nonobjc
fileprivate func reload<C, O>(
using stagedChangeset: Internals.DiffableDataUIDispatcher<O>.StagedChangeset<C>,
deleteSectionsAnimation: @autoclosure () -> RowAnimation,
insertSectionsAnimation: @autoclosure () -> RowAnimation,
reloadSectionsAnimation: @autoclosure () -> RowAnimation,
deleteRowsAnimation: @autoclosure () -> RowAnimation,
insertRowsAnimation: @autoclosure () -> RowAnimation,
reloadRowsAnimation: @autoclosure () -> RowAnimation,
interrupt: ((Internals.DiffableDataUIDispatcher<O>.Changeset<C>) -> Bool)? = nil,
setData: (C) -> Void
) {
if case .none = window, let data = stagedChangeset.last?.data {
setData(data)
self.reloadData()
return
}
for changeset in stagedChangeset {
if let interrupt = interrupt, interrupt(changeset), let data = stagedChangeset.last?.data {
setData(data)
self.reloadData()
return
}
self.cs_performBatchUpdates {
setData(changeset.data)
if !changeset.sectionDeleted.isEmpty {
self.deleteSections(IndexSet(changeset.sectionDeleted), with: deleteSectionsAnimation())
}
if !changeset.sectionInserted.isEmpty {
self.insertSections(IndexSet(changeset.sectionInserted), with: insertSectionsAnimation())
}
if !changeset.sectionUpdated.isEmpty {
self.reloadSections(IndexSet(changeset.sectionUpdated), with: reloadSectionsAnimation())
}
for (source, target) in changeset.sectionMoved {
self.moveSection(source, toSection: target)
}
if !changeset.elementDeleted.isEmpty {
self.deleteRows(at: changeset.elementDeleted.map { IndexPath(row: $0.element, section: $0.section) }, with: deleteRowsAnimation())
}
if !changeset.elementInserted.isEmpty {
self.insertRows(at: changeset.elementInserted.map { IndexPath(row: $0.element, section: $0.section) }, with: insertRowsAnimation())
}
if !changeset.elementUpdated.isEmpty {
self.reloadRows(at: changeset.elementUpdated.map { IndexPath(row: $0.element, section: $0.section) }, with: reloadRowsAnimation())
}
for (source, target) in changeset.elementMoved {
self.moveRow(at: IndexPath(row: source.element, section: source.section), to: IndexPath(row: target.element, section: target.section))
}
}
}
}
@nonobjc
private func cs_performBatchUpdates(_ updates: () -> Void) {
if #available(iOS 11.0, tvOS 11.0, *) {
self.performBatchUpdates(updates)
}
else {
self.beginUpdates()
updates()
self.endUpdates()
}
}
}
#endif