当用户滚动时，Tableviewcell 中的 UISwitch 状态会重置 - Swift

Question

我已经搜索了有关此问题的解决方案，但似乎都不适合我的用例。

我在视图控制器内有一个表，我面临的问题是滚动时 UISwitch 状态重置为 OFF。我知道表格单元格是重复使用的，但是我如何实现一种解决方案，当用户根据下面的代码滚动时，该解决方案将恢复UISwitch的状态

import UIKit
class StirrViewController: UIViewController, UITableViewDelegate, UITableViewDataSource{
@IBOutlet weak var mylabel: UILabel!
var myString = String()
@IBAction func stirrBtn(_ sender: AnyObject) {
}
var timeSelected = String()
var selectedTimeArr = [String]()
override func viewDidLoad() {
super.viewDidLoad()
mylabel.text = myString
self.timeSelected = myString
}
func switchChanged(_ sender : UISwitch!){
print("table row switch Changed (sender.tag)")
print("The switch is (sender.isOn ? "ON" : "OFF")")
let kValue = (sender.tag + 1)
let keyValue = String(kValue)
if sender.isOn {
recipeSettings.boolStirrSwitch[keyValue] = true
recipeSettings.switchedOnArr.append(keyValue)
} else {
recipeSettings.boolStirrSwitch[keyValue] = false
}
}
public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
let stringNum = Int(self.timeSelected)
recipeSettings.recipeTimeSet2 = stringNum!
return(stringNum)!
}

public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
var cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! UITableViewCell
//here is programatically switch make to the table view
let switchView = UISwitch(frame: .zero)
switchView.setOn(false, animated: true)
switchView.tag = indexPath.row // for detect which row switch Changed
switchView.addTarget(self, action: #selector(self.switchChanged(_:)), for: .valueChanged)
cell.accessoryView = switchView
// Process data displayed in rows(minutes)
let endTime = Int(self.timeSelected)
let startTime = Int(1)
// Recipe time array
let timeArray: [Int]  = Array(startTime...endTime!)
let stringTimeArr = timeArray.map{String($0)}
// Save time array to global variable
recipeSettings.recipeTimeSetArr = stringTimeArr
// Create a boolean Array to hold all default false booleans
let defBool: Bool = false
var defBoolArr: [Bool] = []
// Fill the array with the defaults boolean
for _ in 0..<stringTimeArr.count{defBoolArr.append(defBool)}
// Map the array to global dictionary containing the Time in an array and default "false" value
for i in 0..<stringTimeArr.count {
recipeSettings.boolStirrSwitch[stringTimeArr[i]] = defBoolArr[i]
}
// Add the minutes to cell table
cell.textLabel?.text = stringTimeArr[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}

正如您在代码中看到的那样，我确实将每个 UI 开关的状态保存在全局变量字典中。如何解决基于此代码的UISwitch更改状态的问题？感谢所有帮助。提前致谢

Answer 1

var switchState = [String : Bool]()

• 你的recipeSettings.boolStirrSwitch应该像这样清除。
• 当您使用timeSelected时numberOfRowsInSection显示 你的cell.textLabel，所以你不需要额外的stringTimeArr为此。
• 您所做的所有处理cellForRowAt它将再次发生， 再次重复使用表格单元格，以便在另一个中设置数据function然后reloadTableView.

您的问题的解决方案应该是这样的。

import UIKit
class StirrViewController: UIViewController, UITableViewDelegate, UITableViewDataSource{
//make tableView IBOutlet for reloading data
@IBOutlet weak var tableView: UITableView!
@IBOutlet weak var mylabel: UILabel!
var myString = String()
@IBAction func stirrBtn(_ sender: AnyObject) {
}
var timeSelected = String()
var selectedTimeArr = [String]()
override func viewDidLoad() {
super.viewDidLoad()
mylabel.text = myString
self.timeSelected = myString
self.setdefaultSwitchState()
}
//recipeSettings.boolStirrSwitch should be decleard like that
var switchState = [String : Bool]()
//setDeaultSwitchState
func setdefaultSwitchState(){
if let timeSelected = Int(self.timeSelected){
for value in 0..<timeSelected{
switchState["(value)"] = false
//or
//recipeSettings.boolStirrSwitch["(value)"] = false
}
}
self.tableView.reloadData()
}

@objc func switchChanged(_ sender : UISwitch!){
print("table row switch Changed (sender.tag)")
print("The switch is (sender.isOn ? "ON" : "OFF")")
let kValue = (sender.tag + 1)
let keyValue = String(kValue)
if sender.isOn {
switchState[keyValue] = true
} else {
switchState[keyValue] = false
}
}
public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{
let stringNum = Int(self.timeSelected)
recipeSettings.recipeTimeSet2 = stringNum!
return(stringNum)!
}

public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
var cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! UITableViewCell
//here is programatically switch make to the table view
let switchView = UISwitch(frame: .zero)
switchView.setOn(false, animated: true)
switchView.tag = indexPath.row // for detect which row switch Changed
switchView.addTarget(self, action: #selector(self.switchChanged(_:)), for: .valueChanged)
cell.accessoryView = switchView

cell.textLabel?.text = "(indexPath.row + 1)"
if let switchState = switchState["(indexPath.row)"] {
if switchState{
switchView.isOn = true
}else{
switchView.isOn = false
}
}else{
switchView.isOn = false
}
return cell
}

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}