在 Swift 的表格视图中按字母部分显示来自 JSON 的数据

Question

我对 Xcode 和 Swift 还是很陌生。我正在尝试在 TableView 中按字母顺序显示数据（餐厅名称）。我有一个 JSON 文件，可以将每家餐厅分类到正确的社区。代码在视图控制器中完美运行，我在视图控制器中以部分的形式显示社区的名称，并在行中显示餐厅的名称。我的问题是我试图在不同的视图控制器中对所有餐厅名称进行排序，其中部分显示字母（A，B，C ...），并且在每个部分下，我试图按字母顺序显示餐厅，并在边。类似于 iPhone 上的联系人应用程序，但我需要显示餐厅名称的联系人姓名。希望我说得通。 我的代码如下所示：

class BarsViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, SWRevealViewControllerDelegate, UISearchBarDelegate {


@IBOutlet var btnMenuButton: UIBarButtonItem!
@IBOutlet var tableView: UITableView!
@IBOutlet var searchButton: UIBarButtonItem!

var noDataLabel = UILabel()

let urlString = "http://barhoppersf.com/json/neighborhoods.json"

var restaurantArray = Array<Restaurant>()

var filteredRestaurants = [Restaurant]()

var shouldShowSearchResults = false

var searchBar = UISearchBar()
var logoImageView: UIImageView!

let restaurantsName = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z","#"]
let indexName = ["A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z","#"]
let voidIndex = [""]


var restSections = [String]()
var restDictionary = [String : [String]]()

    override func viewDidLoad() {
    super.viewDidLoad()


    self.downloadJsonWithURL() // This loads tableview with data from url 

tableView.reloadData()
} 
   **//JSON FUNC**
func downloadJsonWithURL() {

    let url = NSURL(string: urlString)



    URLSession.shared.dataTask(with: (url as URL?)!, completionHandler: {(data, response, error) -> Void in

        if let error = error {

            print(error.localizedDescription)

            return
        }

        if let data = data {

            guard let json = try? JSONSerialization.jsonObject(with: data) else { return }

            guard let dict = json as? Dictionary<String,Dictionary<String,Dictionary<String,Array<Dictionary<String,String>>>>> else { return }

            guard let hoods = dict["hoods"] else { return }

            guard let names = hoods["neighborhoodNames"] else { return }

            for (key, value) in names {

                let neighborhood = NeighborhoodRestaurants(name: key, data: value)

                self.tableData.append(neighborhood)

                self.tableData.sort { $0.name < $1.name }

                self.filteredRestaurants = self.tableData


            }


            DispatchQueue.main.async {



                self.tableView.reloadData()
            }

        }

    }).resume()
}


func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

    return self.restaurantArray[section].restaurants.count

}

func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {

    return self.restaurantArray[section].name
}

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    tableView.rowHeight = 40

    let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! RestaurantsTableViewCell

    cell.barLabel.text = self.restaurantArray[indexPath.section].restaurants[indexPath.row].name


    return cell
}

我有一个单独的 swift 文件，其中包含 JSON 的所有结构

struct Restaurant {

var name: String
var cuisine: String
var hours: String
var description: String
var address: String
var phone: String
var website: String
var sports: String
var image: String



init?(dict:Dictionary<String,String>) {

    guard

        let name = dict["name"],
        let cuisine = dict["cuisine"],
        let hours = dict["hours"],
        let description = dict["description"],
        let address = dict["address"],
        let phone = dict["phone"],
        let website = dict["website"],
        let sports = dict["sports"],
        let image = dict["image"]


        else {
            return nil
    }

    self.name = name
    self.cuisine = cuisine
    self.hours = hours
    self.description = description
    self.address = address
    self.phone = phone
    self.website = website
    self.sports = sports
    self.image = image


}

//MARK: Function for the data from ViewControler
}

struct NeighborhoodRestaurants {

var name: String

var restaurants: Array<Restaurant>




init(name:String, data:Array<Dictionary<String,String>>) {

    self.name = name

    self.restaurants = Array<Restaurant>()

    for dict in data {

        if let restaurant = Restaurant(dict: dict) {

            self.restaurants.append(restaurant)

            self.restaurants.sort { $0.name < $1.name }

        }

    }
}

}

这是 JSON 文件：http://barhoppersf.com/json/neighborhoods.json

这是社区视图控制器的image，效果很好。你可以得到这个想法！ 再次提前感谢！

Answer 1

我尝试使用一些不同的方法来解决您的问题。这是我制作的Sample。
这是我的控制器代码，并尝试根据 API 提供的数据使其类似于联系人应用程序。我只是在模型中取了餐厅名称，因为它只需要按字母顺序排序。所有其他细节和解释都在代码中的 cmets 中提及。

import UIKit

class ViewController: UIViewController {
    @IBOutlet weak var restaurantsTableView: UITableView!

    //The main array for tableView
    var dataArray = [(String,[Restaurant])]()

    var indexTitles = [String]()

    override func viewDidLoad() {
        super.viewDidLoad()
        getData()
    }

    func getData() {

        let url = URL(string: "http://barhoppersf.com/json/neighborhoods.json")
        URLSession.shared.dataTask(with: url!) { (data, response, error) in

            guard let data = data else {return}

            let json = try? JSONSerialization.jsonObject(with: data, options: .mutableContainers) as! [String : AnyObject]

            guard let hoods = json?["hoods"] else { return }

            guard let names = hoods["neighborhoodNames"] as? [String:[AnyObject]] else { return }

            self.makeDataSource(names: names)

            DispatchQueue.main.async {
                self.restaurantsTableView.reloadData()
            }
        }.resume()
    }

    // The main logic for sorting and making the data like Contacts App tableView
    func makeDataSource(names:[String:[AnyObject]]) {
        //Temporary array to hold restaurants on different indexes
        var dict = [String:[Restaurant]]()

        //Character set taken to check whether the starting key is alphabet or any other character
        let letters = NSCharacterSet.letters

        for (_,value) in names {
            //Iterating Restaurants
            for resObj in value {
                if let restaurantName = resObj["name"] as? String {
                    let restaurant = Restaurant(name: restaurantName)
                    var key = String(describing: restaurant.name.characters.first!)

                    key = isKeyCharacter(key: key, letters: letters) ? key : "#"

                    if let keyValue = dict[key] {
                        //Already value exists for that key
                        var filtered = keyValue
                        filtered.append(restaurant)

                        //Sorting of restaurant names alphabetically
                        filtered = filtered.sorted(by: {$0.0.name < $0.1.name})
                        dict[key] = filtered
                    } else {
                        let filtered = [restaurant]
                        dict[key] = filtered
                    }
                }
            }
        }
        //To sort the key header values
        self.dataArray = Array(dict).sorted(by: { $0.0 < $1.0 })

        //Logic to shift the # category to bottom
        let temp = self.dataArray[0]
        self.dataArray.removeFirst()
        self.dataArray.append(temp)

        //For setting index titles
        self.indexTitles = Array(dict.keys.sorted(by: <))

        //Making the index title # at the bottom
        let tempIndex = self.indexTitles[0]
        self.indexTitles.removeFirst()
        self.indexTitles.append(tempIndex
    }
}

//Function to check whether key is alphabet or not
func isKeyCharacter(key:String,letters:CharacterSet) -> Bool {
    let range = key.rangeOfCharacter(from: letters)
    if let _ = range {
        //Your key is an alphabet
        return true
    }
    return false
}

extension ViewController: UITableViewDataSource, UITableViewDelegate {

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

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return dataArray[section].1.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "RestaurantsTableCell") as! RestaurantsTableCell
        let restaurant = dataArray[indexPath.section].1[indexPath.row]
        cell.restaurantNameLabel.text = restaurant.name
        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

        //Pass this model to detail VC
        let restaurant = dataArray[indexPath.section].1[indexPath.row]

        let detailVC = self.storyboard?.instantiateViewController(withIdentifier: "DetailViewController") as! DetailViewController
        detailVC.restaurant = restaurant
        self.navigationController?.pushViewController(detailVC, animated: true)
    }  

    func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        return 30
    }

    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        return dataArray[section].0
    }

    //For index titles
    func sectionIndexTitles(for tableView: UITableView) -> [String]? {
        return self.indexTitles
    }
}

Restaurant 类现已分离。还修改了链接中的Sample，新建了DetailViewController类。

import Foundation

class Restaurant {
    var name = ""

    init(name:String) {
        self.name = name
    }
}

此代码可以在排序逻辑中进行改进。欢迎改进。

这是输出：

这里是细节控制器：