过滤使用 Firebase 填充的多个数组

Question

我有一个 TextField 用作 SearchView，然后我的 TableView 显示我的结果。 TableView 的原型单元由两个标签组成。第一个标签由 schoolNameArray 填充。第二个标签由 schoolTownArray + ", " + schoolCountryArray 填充。所有 3 个数组都通过 Firebase 填充。搜索功能的图片如下所示。

没有第二个标签，我可以很好地过滤一个数组。我的问题是我只能在一个数组上制作我的 SearchView 过滤器，而不是三个。例如。我输入“Academy”和“Azhar Academy”节目，但如果我输入“Bolton”，我会收到“致命错误：索引超出范围”，因为我无法正确填充过滤后的SchoolLocationArray。

我的 Android 版本的项目从搜索框中检索文本，然后在 firebase 查询的 for 循环中处理过滤。如何使用以下代码在此处执行此操作（或达到相同的结果）：

class SearchViewController: UIViewController {

    @IBOutlet weak var editTextSearch: UITextField!
    @IBOutlet weak var tableViewSearch: UITableView!

    var schoolNameArray = [String]()
    var schoolTownArray = [String]()
    var schoolCountryArray = [String]()
    var filteredSchoolNameArray = [String]()
    var filteredSchoolLocationArray = [String]()
    var searching  = false

    override func viewDidLoad() {
        super.viewDidLoad()

        let schoolDatabase = Database.database().reference().child("Timetable")
        schoolDatabase.observeSingleEvent(of: .value, with: { (snapshot) in
            for child in snapshot.children {
                let schoolID = child as! DataSnapshot
                let stringApproved = schoolID.childSnapshot(forPath: "Approved").value
                if stringApproved as? String == "Yes" {
                    let stringSchoolName = schoolID.childSnapshot(forPath: "Name").value as! String
                    let stringSchoolTown = schoolID.childSnapshot(forPath: "Town or City").value as! String
                    let stringSchoolCountry = schoolID.childSnapshot(forPath: "Country").value as! String
                    self.schoolNameArray.append(stringSchoolName)
                    self.schoolTownArray.append(stringSchoolTown)
                    self.schoolCountryArray.append(stringSchoolCountry)
                }
            }
            self.tableViewSearch.reloadData()
        })
    }
}

extension SearchViewController: UITableViewDataSource, UITableViewDelegate {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if searching {
            return filteredSchoolNameArray.count
        } else {
            return schoolNameArray.count
        }
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let searchItem = tableView.dequeueReusableCell(withIdentifier: "SearchItem") as! SearchItemCell

        searchItem.searchItemSchoolName.text = schoolNameArray[indexPath.row]
        searchItem.searchItemSchoolLocation.text = schoolTownArray[indexPath.row] + ", " + schoolCountryArray[indexPath.row]

        if searching {
            searchItem.searchItemSchoolName.text = filteredSchoolNameArray[indexPath.row]
            searchItem.searchItemSchoolLocation.text = filteredSchoolLocationArray[indexPath.row]
        } else {
            searchItem.searchItemSchoolName.text = schoolNameArray[indexPath.row]
            searchItem.searchItemSchoolLocation.text = schoolTownArray[indexPath.row] + ", " + schoolCountryArray[indexPath.row]
        }

        return searchItem
    }
}

extension SearchViewController: UITextFieldDelegate {    
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        filteredSchoolNameArray = schoolNameArray.filter({$0.lowercased().contains((textField.text?.lowercased())!)})
        searching = true
        tableViewSearch.reloadData()
        return true
    }
}

Answer 1

您应该使用结构来表示您的数据。你会有一个更轻松的时间。您还有一些问题需要解决，但这应该可以帮助您：

class SearchViewController: UIViewController {

    struct School {
        let name: String
        let town: String
        let country: String
    }

    @IBOutlet weak var editTextSearch: UITextField!
    @IBOutlet weak var tableViewSearch: UITableView!

    var schools: [School] = []
    var filteredSchools: [School] = []

    var searching = false

    override func viewDidLoad() {
        super.viewDidLoad()

        // ...

        if stringApproved as? String == "Yes" {
            let name = schoolID.childSnapshot(forPath: "Name").value as! String
            let town = schoolID.childSnapshot(forPath: "Town or City").value as! String
            let country = schoolID.childSnapshot(forPath: "Country").value as! String

            self.schools.append(.init(name: name, town: town, country: country))
        }

        // ...
    }

    // ...
}

extension SearchViewController: UITextFieldDelegate {
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        guard let text = textField.text else { return true }
        filteredSchools = schools.filter({ $0.name.lowercased().contains(text.lowercased()) })
        searching = true
        tableViewSearch.reloadData()
        return true
    }
}

Answer 2

感谢 Rob 的帮助，下面是最终代码。

class SearchViewController: UIViewController {

    @IBOutlet weak var editTextSearch: UITextField!
    @IBOutlet weak var tableViewSearch: UITableView!

    struct School {
        let schoolName: String
        let schoolTown: String
        let schoolCountry: String
    }

    var schoolArray: [School] = []
    var filteredSchoolArray: [School] = []
    var searching  = false

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.

        let schoolDatabase = Database.database().reference().child("Timetable")
        schoolDatabase.observeSingleEvent(of: .value, with: { (snapshot) in
            for child in snapshot.children {
                let schoolID = child as! DataSnapshot
                let stringApproved = schoolID.childSnapshot(forPath: "Approved").value
                if stringApproved as? String == "Yes" {
                    // stringSchoolID = schoolID.key
                    let stringSchoolName = schoolID.childSnapshot(forPath: "Name").value as! String
                    let stringSchoolTown = schoolID.childSnapshot(forPath: "Town or City").value as! String
                    let stringSchoolCountry = schoolID.childSnapshot(forPath: "Country").value as! String
                    self.schoolArray.append(.init(schoolName: stringSchoolName, schoolTown: stringSchoolTown, schoolCountry: stringSchoolCountry))
                }
            }
            self.tableViewSearch.reloadData()
        })
        //filteredSchoolArray.removeAll()
    }
}

extension SearchViewController: UITableViewDataSource, UITableViewDelegate {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if searching {
            return filteredSchoolArray.count
        } else {
            return schoolArray.count
        }
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let searchItem = tableView.dequeueReusableCell(withIdentifier: "SearchItem") as! SearchItemCell

        if searching {
            let filteredSchoolItem = filteredSchoolArray[indexPath.row]
            searchItem.searchItemSchoolName.text = filteredSchoolItem.schoolName
            searchItem.searchItemSchoolLocation.text = filteredSchoolItem.schoolTown + ", " + filteredSchoolItem.schoolCountry
        } else {
            let schoolItem = schoolArray[indexPath.row]
            searchItem.searchItemSchoolName.text = schoolItem.schoolName
            searchItem.searchItemSchoolLocation.text = schoolItem.schoolTown + ", " + schoolItem.schoolCountry
        }

        return searchItem
    }
}

extension SearchViewController: UITextFieldDelegate {
    func textFieldShouldClear(_ textField: UITextField) -> Bool {
        editTextSearch.resignFirstResponder()
        editTextSearch.text = ""
        filteredSchoolArray.removeAll()
        tableViewSearch.reloadData()
        return true
    }

    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        guard let text = textField.text else { return true }
        filteredSchoolArray = schoolArray.filter({$0.schoolName.lowercased().contains(text.lowercased()) ||
            $0.schoolTown.lowercased().contains(text.lowercased()) ||
            $0.schoolCountry.lowercased().contains(text.lowercased())})
        searching = true
        tableViewSearch.reloadData()
        return true
    }
}