This is ReactComponentKit example. EmojiCollection is built on Components, MVVM and Redux.
ReactComponentKit is a library for building a UIViewController based on Component. Additionary, It architect UIViewController as Redux with MVVM. If you use ReactComponentKit, You can make many scenes(UIViewController) more easily. You can share components among scenes.
ReactComponentKit provides easy way to update UICollectionView and UITableView. Using diff, you can easily insert, delete or shuffle items like below :)
We'll defien three actions for our emoji collection app. AddEmojiAction, RemoveEmojiAction and ShuffleEmojiAction.
struct AddEmojiAction: Action {
let section: Int
let emoji: String
}struct RemoveEmojiAction: Action {
let section: Int
let index: Int
}struct ShuffleEmojiAction: Action {
}We need three reducers to mutate our state. There is no when statement and type castring for actions. it is just a pure functions.
func addEmoji(state: EmojiCollectionState, action: AddEmojiAction) -> EmojiCollectionState {
return state.copy {
$0.emoji[action.section].append(action.emoji)
}
}func removeEmoji(state: EmojiCollectionState, action: RemoveEmojiAction) -> EmojiCollectionState {
return state.copy {
$0.emoji[action.section].remove(at: action.index)
}
}func shuffleEmoji(state: EmojiCollectionState, action: ShuffleEmojiAction) -> EmojiCollectionState {
return state.copy {
for (index, var section) in $0.emoji.enumerated() {
section.shuffle()
$0.emoji[index] = section
}
}
}It is needed for our collection view. UICollectionView in ReactComponentKit is built up on the models for items and sections.
func makeCollectionViewSectionModels(state: EmojiCollectionState) -> EmojiCollectionState {
let emojiGroupList = state.emoji
let sections = emojiGroupList.enumerated().map { (groupIndex, emojiGroup) -> DefaultSectionModel in
let emojiBoxModels = emojiGroup.map({ (emoji) -> EmojiBoxModel in
EmojiBoxModel(emoji: emoji)
})
let section = DefaultSectionModel(items: emojiBoxModels, header: EmojiSectionHeaderModel(title: " Emoji Section \(groupIndex)"), footer: nil)
section.minimumInteritemSpacing = 0
section.minimumLineSpacing = 2
section.inset = UIEdgeInsets(top: 0, left: 8, bottom: 0, right: 8)
return section
}
return state.copy { $0.sections = sections }
}We need to define ViewModel and in there we should setup store and define action flows.
We can define action flows in initStore block. We couldn't access the store directly so we should access it with initStore method.
override func setupStore() {
initStore { store in
store.initial(state: EmojiCollectionState())
store.beforeActionFlow(logAction)
store.flow(action: AddEmojiAction.self)
.flow(
addEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
store.flow(action: RemoveEmojiAction.self)
.flow(
removeEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
store.flow(action: ShuffleEmojiAction.self)
.flow(
shuffleEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
}
}struct EmojiCollectionState: State {
var emoji: [[String]] = [[], [], []]
var sections: [DefaultSectionModel] = []
var error: RCKError? = nil
}
class EmojiCollectionViewModel: RCKViewModel<EmojiCollectionState> {
private var emojiGroupList: [[String]]? = nil
let sections = Output<[DefaultSectionModel]>(value: [])
override func setupStore() {
initStore { store in
store.initial(state: EmojiCollectionState())
store.beforeActionFlow(logAction)
store.flow(action: AddEmojiAction.self)
.flow(
addEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
store.flow(action: RemoveEmojiAction.self)
.flow(
removeEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
store.flow(action: ShuffleEmojiAction.self)
.flow(
shuffleEmoji,
{ state, _ in makeCollectionViewSectionModels(state: state) }
)
}
}
override func on(newState: EmojiCollectionState) {
emojiGroupList = newState.emoji
sections.accept(newState.sections)
}
func randomIndexToDelete(at section: Int) -> Int? {
guard let emojiGroupList = emojiGroupList else { return nil }
guard emojiGroupList[section].count > 0 else { return nil }
return Int(arc4random()) % emojiGroupList[section].count
}
}The MIT License
Copyright © 2018 Sungcheol Kim, https://github.com/ReactComponentKit/EmojiCollectionView
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.