ios - swift 3.0 TableViewCell : Saving the Status of a Button and Having it Persist

Question

目前，我有一个 tableview 设置为 tableviewcell 的子类。在此 tableviewcell 上，我有一个显示添加或显示的按钮。我想知道是否有一种方法可以存储按钮相对于其行的状态。例如，我有一个搜索栏和这个表格 View ，如果我将表格 View 第四行的按钮状态更改为从添加中减去，然后在搜索栏中搜索特定行，它将显示在第一行，但不会保留按钮的状态。我想知道是否有一种方法可以在不使用后端(或数据库)的情况下做到这一点。

func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {

    filtered = data.filter({ (text) -> Bool in
        let tmp: NSString = text as NSString
        let range = tmp.range(of: searchText, options: NSString.CompareOptions.caseInsensitive)
        return range.location != NSNotFound
    })
    if (filtered.count == 0){
        searchActive = false
    } else {
        searchActive = true
    }
    self.TableView.reloadData()
}


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

}

func numberOfSections(in tableView: UITableView) -> Int {
    return 1
}

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    if searchActive == true {
        return filtered.count
    }
    return data.count
}

var status = [IndexPath: Bool]()

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! ListCell
    cell.cellDelegate = self
    cell.contentView.bringSubview(toFront: cell.Button)


    if status[indexPath] ?? false {

        cell.Button.setTitle("Subtract", for: .normal)
    } else {

        cell.Button.setTitle("Add", for: .normal)
    }

    cell.indexPath = indexPath

    if(searchActive) {
        cell.textLabel?.text = filtered[indexPath.row]
    } else {
        cell.textLabel?.text = data[indexPath.row]
    }

    cell.contentView.bringSubview(toFront: cell.Button)
    return cell
}

func didPressButton(indexPath: IndexPath) {

    guard let cell = TableView.cellForRow(at: indexPath) as? ListCell else {
        return
    }

    if status[indexPath] ?? false {
        status[indexPath] = false
        cell.Button.setTitle("Add", for: .normal)

    } else {
        status[indexPath] = true
        cell.Button.setTitle("Subtract", for: .normal)

    }
}

Answer 1

感谢您对我的指导。这就是我所拥有的有效方法。在我的数据数组中，我在每个项目中添加了另一个唯一的条目(A、B、C)。然后我用 我的状态数组中的这个键值来确定它是否已被添加。如果有更有效的方法，请告诉我。

var data = [["Apples","A"],["Bananas","B"],["Corn","C"],["Doughnuts","D"],["Eggplant","E"],["Flour","F"]]
var filtered: [[String]] = []
var searchActive : Bool = false 
var status = [String: Bool]()
var name : String = String()
var filteredName : String = String()

func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {

    filtered = data.filter({ (text) -> Bool in
        let tmp: NSString = text[0] as NSString
        let range = tmp.range(of: searchText, options: NSString.CompareOptions.caseInsensitive)
        return range.location != NSNotFound
    })
    if (filtered.count == 0){
        searchActive = false
    } else {
        searchActive = true
    }
    self.guestTableView.reloadData()
}


func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    print("Hello")  
}

func numberOfSections(in tableView: UITableView) -> Int {
    return 1
}

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    if searchActive == true {
        return filtered.count
    }
    return data.count
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! GuestListCell
    cell.cellDelegate = self
    cell.contentView.bringSubview(toFront: cell.button)


    item = data[indexPath.row][1]


    if status[item] ?? false {
        cell.button.setTitle("Subtract", for: .normal)
    } else {
        cell.button.setTitle("Add", for: .normal)
    }

    cell.indexPath = indexPath

    if(searchActive) {
        cell.textLabel?.text = filtered[indexPath.row][0]

        if status[filtered[indexPath.row][1]] ?? false {
            cell.button.setTitle("Subtract", for: .normal)
        } else {
            cell.button.setTitle("Add", for: .normal)
        }
    } else {
        filteredName = data[indexPath.row][1]
        cell.textLabel?.text = data[indexPath.row][0]
    }
    cell.contentView.bringSubview(toFront: cell.button)
    return cell
}

func didPressButton(indexPath: IndexPath) {

    guard let cell = guestTableView.cellForRow(at: indexPath) as? GuestListCell else {
        return
    }

    if searchActive {

        if status[filtered[indexPath.row][1]] ?? false {
            print("the value of searchActive is \(searchActive)")
            status[filtered[indexPath.row][1]] = false
            cell.button.setTitle("Add", for: .normal)
        } else {
            status[filtered[indexPath.row][1]] = true
            cell.button.setTitle("Subtract", for: .normal)

        }

    } else {

        if status[data[indexPath.row][1]] ?? false {

            status[data[indexPath.row][1]] = false
            cell.button.setTitle("Add", for: .normal)
        } else {
            status[data[indexPath.row][1]] = true
            cell.button.setTitle("Subtract", for: .normal)
        }
    }

}