michzio

//
//  ContentView.swift
//  Test
//
//  Created by Michal Ziobro on 03/04/2020.
//  Copyright © 2020 click5 Interactive. All rights reserved.
//

import SwiftUI

michzio

struct CollectionView<Section: Hashable & CaseIterable, Item: Hashable>: UIViewControllerRepresentable {

    // MARK: - Properties
    let layout: UICollectionViewLayout
    let sections: [Section]
    let items: [Section: [Item]]

    // MARK: - Actions
    let snapshot: (() -> NSDiffableDataSourceSnapshot<Section, Item>)?
    let content: (_ indexPath: IndexPath, _ item: Item) -> AnyView

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CollectionView(layout: createLayout(),
                           sections: self.sections,
                           items: [
                            .feature : Item.featureItems,
                            .categories : Item.categoryItems
                            ],
                           supplementaryKinds: ["header", "footer"],
                           supplementaryContent: { kind, indexPath, item in
                        
                            switch kind {

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class CollectionViewController<Section, Item>: UIViewController, UICollectionViewDelegate
    where Section : Hashable & CaseIterable, Item : Hashable {
    
    // MARK: - Injections
    var layout: UICollectionViewLayout! = nil
    var snapshot : NSDiffableDataSourceSnapshot<Section, Item>! = nil
    var content: ((_ indexPath: IndexPath, _ item: Item) -> AnyView)! = nil
        
    var supplementaryKinds: [String]! = nil
    var supplementaryContent: ((_ kind: String, _ indexPath: IndexPath, _ item: Item?) -> AnyView)? = nil

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// MARK: - Setup
extension CollectionViewController {
    
    private func configureCollectionView() {
        view.addSubview(collectionView)
        
        collectionView.register(HostingControllerCollectionViewCell<AnyView>.self, forCellWithReuseIdentifier: HostingControllerCollectionViewCell<AnyView>.reuseIdentifier)
        
        collectionView.register(BadgeSupplementaryView.self, forSupplementaryViewOfKind: "badge", withReuseIdentifier: BadgeSupplementaryView.reuseIdentifier)
        collectionView.register(EmptySupplementaryView.self, forSupplementaryViewOfKind: "badge", withReuseIdentifier: EmptySupplementaryView.reuseIdentifier)

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 extension CollectionViewController {
     private func cellProvider(_ collectionView: UICollectionView, _ indexPath: IndexPath, _ item: Item) -> UICollectionViewCell? {
        
        guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: HostingControllerCollectionViewCell<AnyView>.reuseIdentifier, for: indexPath) as? HostingControllerCollectionViewCell<AnyView> else {
            fatalError("Could not load cell")
        }
        
        cell.host(content(indexPath, item))
        cell.backgroundColor = .green
        

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extension CollectionViewController {
private func supplementaryViewProvider(collectionView: UICollectionView, kind: String, indexPath: IndexPath) -> UICollectionReusableView? {
    
        if kind == "badge" {
            return badgeViewProvider(collectionView, kind, indexPath)
        } else {
            return contentSupplementaryProvider(collectionView, kind, indexPath)
        }
    }
    

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class HostingControllerCollectionViewCell<Content: View> : UICollectionViewCell {

    var controller: UIHostingController<Content>?
    
    func host(_ view: Content, parent: UIViewController? = nil) {
        
        if let controller = controller {
            controller.rootView = view
            controller.view.layoutIfNeeded()
        } else {

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class HostingControllerCollectionReusableView<Content: View>: UICollectionReusableView {
   
    var controller: UIHostingController<Content>?
    
    func host(_ view: Content, parent: UIViewController? = nil) {
        
        if let controller = controller {
            controller.rootView = view
            controller.view.layoutIfNeeded()
        } else {

michzio

struct CollectionView<Section: Hashable & CaseIterable, Item: Hashable>: UIViewControllerRepresentable {
    
    // MARK: - Properties
    let layout: UICollectionViewLayout
    let sections: [Section]
    let items: [Section: [Item]]
    let supplementaryKinds: [String]
    let animateChanges: Bool?
    
    // MARK: - Actions