ios - UITableView 只显示 10 个单元格/行

Question

我的 TableViewController 上有两个范围/选项卡，“全部”和“前 10 个”。我只希望我的“前 10 个”选项卡只显示 10 个单元格/行，而不是显示所有内容。请查看我的图片以获得更好的引用。

P.S:我的 UITableView 用于使用 firebase 数据库显示我的事件的 30 多个展位的实时结果。另外，case 0 是“All”，case 1 是“Top 10”。

表格 View Controller

import UIKit
import FirebaseDatabase

var ref: DatabaseReference?
var databaseHandle: DatabaseHandle?
var postData = [String]()
var postData2 = [String]()
var currentpostDataArray = [String]()
var tableDataArray = [tableData]()
var tableDataArray2 = [tableData]()
var searchArray = [tableData]()
var selectedTab = 0

class TableViewController: UITableViewController, UISearchBarDelegate {


    @IBOutlet var searchBar: UISearchBar!

    override func viewDidLoad() {
        super.viewDidLoad()

        setUpSearchBar()

        ref = Database.database().reference()//set the firebase reference

            databaseHandle = ref?.child("Posts2").observe(.value, with: { (snapshot) in
                // Code to execute when a child is added under "Posts"
                postData.removeAll()
                postData2.removeAll()
                tableDataArray.removeAll()


                for child in snapshot.children {
                    let snap = child as! DataSnapshot
                    let key = snap.key
                    let value = String(describing: snap.value!)
                    let rating = (value as NSString).integerValue

                    postData.append(key)
                    postData2.append(value)

                    tableDataArray.append(tableData(boothName: key, boothRating: rating))
                    currentpostDataArray = postData
                }

                self.tableView.reloadData()


            })

        databaseHandle = ref?.child("Posts2").queryOrderedByValue().queryLimited(toLast: 10).observe(.value, with: { (snapshot) in
            // Code to execute when a child is added under "Posts"
            postData.removeAll()
            postData2.removeAll()
            tableDataArray2.removeAll()


            for child in snapshot.children {
                let snap = child as! DataSnapshot
                let key = snap.key
                let value = String(describing: snap.value!)
                let rating = (value as NSString).integerValue

                postData.append(key)
                postData2.append(value)

                tableDataArray2.append(tableData(boothName: key, boothRating: rating))
                currentpostDataArray = postData
            }

            self.tableView.reloadData()


        })

    }


    private func setUpSearchBar() {
        searchBar.delegate = self
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
            return currentpostDataArray.count
    }




    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)

        cell.textLabel?.text = currentpostDataArray[indexPath.row]
        cell.detailTextLabel?.text = postData2[indexPath.row] + " ♥"
        cell.detailTextLabel?.textColor = UIColor.red;
        return cell
    }


    func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
        switch searchBar.selectedScopeButtonIndex {
        case 0:
            selectedTab = 0
            searchArray.removeAll()
            searchArray = tableDataArray
            currentpostDataArray.removeAll()
            postData2.removeAll()
            if !searchText.isEmpty {
                for data in searchArray {
                    let item = data.boothName
                    if (item.lowercased().range(of: searchText.lowercased()) != nil)
                    {
                        currentpostDataArray.append(data.boothName)
                        let value = String(describing: data.boothRating)
                        postData2.append(value)
                    }
                }
            }
            else {
                loadDara()
            }
            self.tableView.reloadData()
        case 1:
            selectedTab = 1
            searchArray.removeAll()
            searchArray = tableDataArray2
            currentpostDataArray.removeAll()
            postData2.removeAll()
            if !searchText.isEmpty {
                for data in searchArray {
                    let item = data.boothName
                    if (item.lowercased().range(of: searchText.lowercased()) != nil)
                    {
                        currentpostDataArray.append(data.boothName)
                        let value = String(describing: data.boothRating)
                        postData2.append(value)
                    }
                }
            }
            else {
                loadDara2()
            }
            self.tableView.reloadData()
        default:
            break
        }
    }


    func searchBar(_ searchBar: UISearchBar, selectedScopeButtonIndexDidChange selectedScope: Int) {
        switch selectedScope {
        case 0:
            currentpostDataArray.removeAll()
            postData2.removeAll()
            for data in tableDataArray {
                currentpostDataArray.append(data.boothName)

                let value = String(describing: data.boothRating)
                postData2.append(value)
            }
            self.tableView.reloadData()

        case 1:
            currentpostDataArray.removeAll()
            postData2.removeAll()
            let sortedTableData = tableDataArray2.sorted(by: { $0.boothRating > $1.boothRating })
            for data in sortedTableData {
                currentpostDataArray.append(data.boothName)

                let value = String(describing: data.boothRating)
                postData2.append(value)
            }
            self.tableView.reloadData()

        default:
            break

        }
        tableView.reloadData()
    }

    func loadDara() {
        for data in tableDataArray {
            currentpostDataArray.append(data.boothName)

            let value = String(describing: data.boothRating)
            postData2.append(value)
        }

    }

    func loadDara2() {
        let sortedTableData = tableDataArray2.sorted(by: { $0.boothRating > $1.boothRating })
        for data in sortedTableData {
            currentpostDataArray.append(data.boothName)

            let value = String(describing: data.boothRating)
            postData2.append(value)
        }
    }

}

class tableData {
    var boothName: String
    var boothRating: Int
    init(boothName: String, boothRating: Int) {
        self.boothName = boothName
        self.boothRating = boothRating
    }
}

Answer 1

在您的 View Controller 中声明一个变量，指向选择的段

var selectedTab = 0

在 selectedScopeButtonIndexDidChange 中，根据选择更改为上述变量赋值:

func searchBar(_ searchBar: UISearchBar, selectedScopeButtonIndexDidChange selectedScope: Int) {
            switch selectedScope {
            case 0:
                selectedTab = 0
                currentpostDataArray.removeAll()
                postData2.removeAll()
                for data in tableDataArray {
                    currentpostDataArray.append(data.boothName)

                    let value = String(describing: data.boothRating)
                    postData2.append(value)
                }
                self.tableView.reloadData()

            case 1:
                selectedTab = 1
                currentpostDataArray.removeAll()
                postData2.removeAll()
                let sortedTableData = tableDataArray.sorted(by: { $0.boothRating > $1.b

oothRating })
            for data in sortedTableData {
                currentpostDataArray.append(data.boothName)

                let value = String(describing: data.boothRating)
                postData2.append(value)
            }
            self.tableView.reloadData()

        default:
            break

        }
        tableView.reloadData()
    }

在 numberOfRowsInSection 中，检查选定的段并设置行数:

override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
            if selectedTab = 0 {
              return currentpostDataArray.count
            } else {
              if currentpostDataArray.count >= 10 {
                return 10
              } else {
                return currentpostDataArray.count
              }
            }
 }