how to update the UITableView data while scrolling - ios

Question

I have displayed data in the UITableView.The listing is for add cart items in cart list.
According to this picture can see the following details:-
price
Name of product
Stepper to add the quantity
Total Amount
So for this Firstly I added the product in the UITableView. Then stepper action to increases or decreases the quantity, I given the code according .
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let identifier = "cell"
var cell: ChartCell! = tableView.dequeueReusableCell(withIdentifier: identifier) as? ChartCell
if cell == nil {
tableView.register(UINib(nibName: "ChartCell", bundle: nil), forCellReuseIdentifier: identifier)
cell = tableView.dequeueReusableCell(withIdentifier: identifier) as? ChartCell
}
cell.setEventData(carts: chartViewModel.datafordisplay(atindex: indexPath))
cell.cartadd = { [weak self] in
if let i = self?.tableView.indexPath(for: $0) {
let productid = self?.chartViewModel.datafordisplay(atindex: indexPath)
print(productid?.cartid)
self?.chartViewModel.search(idsearch:productid?.cartid)
print(self?.chartViewModel.searchindex(objectatindex: 0))
cell.setcartData(cartsadd: (self?.chartViewModel.searchindex(objectatindex:0))!)
print(cell.quantity)
self?.chartViewModel.totalPriceInCart()
let theIntegerValue1 :[Int] = (self?.chartViewModel.totalvalue)!
let result = "\(theIntegerValue1[0])"
print(result)
let theStringValue1 :String = String(describing: result)
print(theStringValue1)
self?.totalresult.text = theStringValue1
print(i)
}
}
the viewmodel:-
class ChartViewModel: NSObject {
var datasourceModel:ChartDataSourceModel
var totalvalue:[Int] = []
var insertedArray:CartModel?
var filteredListArray:Array<CartModel>? = []
var productArray:CartModel?
var finalListArray:Array<CartModel>? = []
init(withdatasource newDatasourceModel: ChartDataSourceModel) {
datasourceModel = newDatasourceModel
print(datasourceModel.dataListArray)
}
func search(idsearch :String?) {
filteredListArray = datasourceModel.dataListArray?.filter{($0.cartid?.range(of: idsearch!, options: .caseInsensitive) != nil)}
print(filteredListArray)
}
func searchindex(objectatindex index: Int) -> CartModel {
return self.filteredListArray![index]
}
func datafordisplay(atindex indexPath: IndexPath) -> CartModel{
return datasourceModel.dataListArray![indexPath.row]
}
func numberOfRowsInSection(section:Int) -> Int {
return datasourceModel.dataListArray!.count
}
func delete(atIndex indexPath: IndexPath) {
datasourceModel.dataListArray!.remove(at: indexPath.row)
print(datasourceModel.dataListArray)
}
func totalPriceInCart() {
var totalPrice: Int = 0
for product in datasourceModel.dataListArray! {
totalPrice += product.cartsumint!
print(totalPrice)
}
self.totalvalue = [totalPrice]
}
func insert(atIndex indexPath: IndexPath) {
print(productArray)
print(datasourceModel.dataListArray)
datasourceModel.dataListArray!.insert(productArray!, at: indexPath.row)
print(datasourceModel.dataListArray)
self.datasourceModel.dataListArray = datasourceModel.dataListArray
print(datasourceModel.dataListArray)
self.finalListArray = self.datasourceModel.dataListArray
}
func add() {
datasourceModel.dataListArray?.append(insertedArray!)
print(datasourceModel.dataListArray)
print(insertedArray?.offerAddName)
print(insertedArray?.offerprice)
self.datasourceModel.dataListArray = datasourceModel.dataListArray
print(insertedArray?.cartsum)
}
}
The above code is to add the quantity. And this code is given in UITableView cellForRowAt delegate.
But the problem is:-
-As i adding the quantity of product ,the price also changes And will display in the UITableView. But while scrolling the UITableView the data will show as before.That means :-
initial suppose:- product name : car, price: 300, quantity: 1
This will show at UITableView. When I added quantity: 2, So price: 600 this will show in the UITableView.
But the problem is while scrolling the UITableView it become as price: 300, quantity: 1.
So how to update the UITableView. what should do
The UITableviewCell:-
func setEventData(carts:QM_CartModel)
{
self.name.text = carts.cartname
self.price.text = carts.carttotalprice
self.itemQuantityStepper.value = 1
setItemQuantity(quantity)
print(self.price.text)
let value = carts.cartsum
let x: Int? = Int(value!)
print(x)
let add = x!
print(add)
let theIntegerValue1 :Int = add
let theStringValue1 :String = String(theIntegerValue1)
// self.price.text = theStringValue1
self.price.text = "QR \(theStringValue1)"
print(self.price.text)
}
func setcartData(cartsadd:QM_CartModel)
{
let theIntegerValue :Int = self.quantity
let theStringValue :String = String(theIntegerValue)
cartsadd.cartquantity = theStringValue
print(cartsadd.cartquantity)
print(cartsadd.cartsum)
let value = cartsadd.cartsum
let qty = cartsadd.cartquantity
let x: Int? = Int(value!)
print(x)
let y: Int? = Int(qty!)
print(y)
let add = x! * y!
print(add)
let theIntegerValue1 :Int = add
let theStringValue1 :String = String(theIntegerValue1)
// self.price.text = theStringValue1
self.price.text = "QR \(theStringValue1)"
print(self.price.text)
cartsadd.cartsumint = theIntegerValue1
// print(cartsadd.cartsum)
}

Answer 1

You need to store your data(updated) in your model class.Because while scrolling tableview dequeuereusablecell again call and it will get data from model that's why you always get old data.

Answer 2

class TableViewCellData {
var data: Any?
}
-
class TableViewCell: UITableViewCell {
var cellData: TableViewCellData?
{
didSet {
// change data in cell from TableViewCellData
}
}
var cartadd: (() -> Void)?
}
-
class ViewController: UITableViewController {
var dataSource: [TableViewCellData] = []
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "identifier", for: indexPath) as! TableViewCell
cell.cellData = dataSource[indexPath.row]
cell.cartadd = {
cell.cellData?.data = "" // set data to TableViewCellData
}
return cell
}
}