你如何在 tableview 中对部分进行分组？

Question

我想做的是将 TableView 中的部分分组。通过按 storeName 对它们进行排序，以便我可以将项目分开以转到其适当的部分并按 StoreName.

排列

我试图在每个商店的列表中显示几个不同的项目部分。通过根据 StoreName 对部分进行分组。

Items 数组包含每个部分中每个项目的所有项目，并显示该项目属于哪个商店。

我如何能够对特定商店的部分进行分组？

我知道我很擅长对我的部分进行分组，但我只是不确定如何使其正常工作以及如何连接到我的 Custom HeaderCell。我在我的 StoreVC 中编写了一个名为 attemptToAssembleStoreGroups()

的函数

我只是想知道我如何才能根据 storeName 将我的商品分组在一起，以便每个商店都有自己的部分，并有自己的商品列表。

struct ItemSelection {
    let store: String
    let productName: String
    let productImage: UIImage
    let quantity: String
    let total: String
}

struct ItemSection {
    let title : String
    let stores : [ItemSelection]
}

class StoreVC: UITableViewController {

      fileprivate let cellId = "id123"

        let items = [
          ItemSelection(store: "Walmart",
               productName: "Bionicle",
               productImage: #imageLiteral(resourceName: "Bionicle"),
               quantity: "4",
               total: "24"),
          ItemSelection(store: "Walmart",
               productName: "PokeBall",
               productImage: #imageLiteral(resourceName: "PokeBall"),
               quantity: "2",
               total: "30"),
          ItemSelection(store: "Target",
               productName: "Beer",
               productImage: #imageLiteral(resourceName: "Beer"),
               quantity: "2",
               total: "30"),
          ItemSelection(store: "Lego Store",
               productName: "Star Wars Set",
               productImage: #imageLiteral(resourceName: "Star_Wars_Set"),
               quantity: "4",
               total: "256"),
          ItemSelection(store: "Lego Store",
               productName: "Indiana Jones Set",
               productImage: #imageLiteral(resourceName: "Indiana_Jones_Set"),
               quantity: "2",
               total: "88"),
          ItemSelection(store: "Amazon",
               productName: "Coconut Milk",
               productImage: #imageLiteral(resourceName: "Coconut_Milk"),
               quantity: "4",
               total: "20"),
          ItemSelection(store: "Amazon",
               productName: "32 inch Tv",
               productImage: #imageLiteral(resourceName: "TV"),
               quantity: "1",
               total: "156"),
          ItemSelection(store: "Amazon",
               productName: "Amazon Echo",
               productImage: #imageLiteral(resourceName: "Amazon_Echo"),
               quantity: "1",
               total: "80"),
          ItemSelection(store: "Amazon",
               productName: "Grill",
               productImage: #imageLiteral(resourceName: "Grill"),
               quantity: "3",
               total: "90"),
          ItemSelection(store: "Amazon",
               productName: "Coconut Bar",
               productImage: #imageLiteral(resourceName: "coconuts"),
               quantity: "4",
               total: "240")
         ]

      var itemSelection = [[ItemSelection]]()
      var storeArray = [String]()
      var itemSections = [ItemSection]()

     override func viewDidLoad() {
        super.viewDidLoad()

        for index in self.items {
            storeArray.append(index.store)
        }

        let groupedDictionary = Dictionary(grouping: items, by: {String([=10=].store.prefix(1))})
        let keys = groupedDictionary.keys.sorted()
        itemSections = keys.map{ItemSection(title: [=10=], stores: groupedDictionary[[=10=]]!.sorted(by: {[=10=].store < .store}))}
     }



     override func numberOfSections(in tableView: UITableView) -> Int {
         return itemSections.count
     }

     override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
         return itemSections[section].stores.count
     }

     override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         let cell = tableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! StoreCell
         let itemSelections = itemSelection[indexPath.section][indexPath.row]
         cell.itemSelction = itemSelections
         return cell
     }

     override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
         let cartHeader = tableView.dequeueReusableCell(withIdentifier: "Header") as! HeaderCell

         let stores = itemSelection[section]

         cartHeader.storeName.text = "Store: \(stores)"

         return cartHeader
     }

     override func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
         return 45
     }

}

class StoreCell: UITableViewCell {

    @IBOutlet weak var itemQty: UILabel!
    @IBOutlet weak var itemName: UILabel!
    @IBOutlet weak var itemPrice: UILabel!
    @IBOutlet weak var itemImage: UIImage!

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

    var itemSelection: ItemSelection! {
        didSet {
            itemName.text = itemSelection.productName
            itemQty.text = "Qty: \(itemSelection.quantity)"
            itemPrice.text = "$\(itemSelection.total)"
            itemImage.image = itemSelection.productImage
        }

    }

}

class HeaderCell: UITableViewCell {

    @IBOutlet weak var storeName: UILabel!

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

}

Answer 1

找到我的解决方案

import Foundation

struct Items {
    let store: String
    let productName: String
    let productImage: UIImage
    let quantity: String
    let price: String
}

extension Items: Comparable {
    static func < (lhs: Items, rhs: Items) -> Bool {
        if lhs.store < rhs.store { return true }
        else { return lhs.store == rhs.store && lhs.productName < rhs.productName }
    }
}

extension Items {
    static let retail: [Items] = [
        .init(store: "Amazon",
              productName: "Care Bear",
              productImage: #imageLiteral(resourceName: "Bear"),
              quantity: "4",
              price: "156"),
        .init(....
    ]
}

import Foundation

class ItemDataSource: NSObject {
    var sections: [String: [Items]] = [:]

    var items: [String] {
        return sections.keys.sorted()
    }

    var indexes: [String] {
        return items
            .map { String([=11=].first!) }
            .reduce(into: Set<String>(), { [=11=].insert() })
            .sorted()
    }

    init(stores: [Items]) {
        for store in retail.sorted(by: <) {
            let items = store.items
            if var stores = sections[items] {
                stores.append(store)
                sections[items] = stores
            } else {
                sections[items] = [store]
            }
        }
    }
}

class StoreHeader: UITableViewCell {

    @IBOutlet weak var dispensaryName: UILabel!

    var store: String? {
        didSet { storeName.text = "Store: \(store!)" }
    }

}

class StoreCell: UITableViewCell {

    @IBOutlet weak var productImage: UIImageView!
    @IBOutlet weak var productQty: UILabel!
    @IBOutlet weak var productPrice: UILabel!
    @IBOutlet weak var productName: UILabel!

    var product: String? {
        didSet { productName.text = product }
    }
    var quantity: String? {
        didSet { productQty.text = "Qty: \(quantity!)" }
    }
    var price: String? {
        didSet { productPrice.text = "$\(price!)" }
    }
    var img: UIImage? {
        didSet { productImage.image = img }
    }

}

import UIKit

class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

    let dataSource: ItemDataSource = .init(stores: Items.stores)

    @IBOutlet weak var tableView: UITableView!

    func numberOfSections(in tableView: UITableView) -> Int {
        return dataSource.sections.count
    }
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        let store = dataSource.items[section]
        return dataSource.sections[store]?.count ?? 0
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
         let storeCell = tableView.dequeueReusableCell(withIdentifier: "StoreCell") as! StoreCell
        let store = dataSource.items[indexPath.section]
        let storeItem = dataSource.sections[store]?[indexPath.row]

        storeCell.product = storeItem?.productName
        storeCell.price = storeItem?.price
        storeCell.quantity = storeItem?.quantity
        storeCell.img = storeItem?.productImage

        return storeCell
    }
    func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
        let storeHeader = tableView.dequeueReusableCell(withIdentifier: "StoreHeader") as! StoreHeader
        storeHeader.store = dataSource.items[section]
        return storeHeader
    }
    func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        return 45
    }

Answer 2

或者，您可以将 ItemSelection 内容分解成一个单独的 class。

Dictionary(grouping:by:) 使您能够将数组转换为按您指定的任何键分组的字典。下面的代码按商店名称对其进行分组。

我使用了 lazy 变量，因此在初始化 class 时它们并没有全部初始化。一切都在需要时进行初始化。

storeNames 从字典键中检索。

通过从我从初始数组创建的字典中查找值来检索每个商店的元素。

class StoreInfoDataManager {

    struct ItemSelection {
        let storeName: String
        let productName: String
        let productImage: UIImage
        let quantity: String
        let total: String
    }

    lazy var storeDictionary: [String: [ItemSelection]] = {
        return Dictionary(grouping: itemSelections) { [=10=].storeName }
    }()

    // These are the keys for your sections
    lazy var storeNames: [String] = {
        return Array(storeDictionary.keys).sorted()
    }()

    // This returns an array of items in the store
    func items(for store: String) -> [ItemSelection]? {
        return storeDictionary[store]
    }

    lazy var itemSelections: [ItemSelection] = {
        return [
            ItemSelection(storeName: "Walmart",
                          productName: "Bionicle",
                          productImage: #imageLiteral(resourceName: "Bionicle"),
                          quantity: "4",
                          total: "24"),
            ItemSelection(storeName: "Walmart",
                          productName: "PokeBall",
                          productImage: #imageLiteral(resourceName: "PokeBall"),
                          quantity: "2",
                          total: "30"),
            ItemSelection(storeName: "Target",
                          productName: "Beer",
                          productImage: #imageLiteral(resourceName: "Beer"),
                          quantity: "2",
                          total: "30"),
            ItemSelection(storeName: "Lego Store",
                          productName: "Star Wars Set",
                          productImage: #imageLiteral(resourceName: "Star_Wars_Set"),
                          quantity: "4",
                          total: "256"),
            ItemSelection(storeName: "Lego Store",
                          productName: "Indiana Jones Set",
                          productImage: #imageLiteral(resourceName: "Indiana_Jones_Set"),
                          quantity: "2",
                          total: "88"),
            ItemSelection(storeName: "Amazon",
                          productName: "Coconut Milk",
                          productImage: #imageLiteral(resourceName: "Coconut_Milk"),
                          quantity: "4",
                          total: "20"),
            ItemSelection(storeName: "Amazon",
                          productName: "32 inch Tv",
                          productImage: #imageLiteral(resourceName: "TV"),
                          quantity: "1",
                          total: "156"),
            ItemSelection(storeName: "Amazon",
                          productName: "Amazon Echo",
                          productImage: #imageLiteral(resourceName: "Amazon_Echo"),
                          quantity: "1",
                          total: "80"),
            ItemSelection(storeName: "Amazon",
                          productName: "Grill",
                          productImage: #imageLiteral(resourceName: "Grill"),
                          quantity: "3",
                          total: "90"),
            ItemSelection(storeName: "Amazon",
                          productName: "Coconut Bar",
                          productImage: #imageLiteral(resourceName: "coconuts"),
                          quantity: "4",
                          total: "240")
        ]
    }()
}

你如何在 tableview 中对部分进行分组？

How do you do you group sections in tableview?

arrays

tableview

ios

sections

swift