Is it posibble in Swift, to append a value of a UITableViewCell to a array of Strings?

Question

I am making an app where you can store a products name and its price in a Realm dataBase and show it in a UItableViewController and in another UITAbleViewController to show only the name of the product and if you press on the Cell, I want that the product name appends to an Array of Strings and the price of that product(which is not shown on that Particular cell) to be appended to another Array of Doubles. is that possible? if yes, how do I do that?

I searched on google and I found an answer on StackOverflow: getting data from each UITableView Cells Swift but his Answer didn't help, that is why I am writing this question.

I added this part of the answer to the question on stackOverFlow I mentioned above:

selectedProductsForSell.append(cell?.value(forKeyPath: item.name) as! String)

but I don't know how to append the connected price to another array

When I run the app on an iPad, when I tab the cell to append the value (what is the name of the product) to an array, it gives the following error:

terminating with uncaught exception of type NSException

and it goes to the appDelegate.swift

any ideas on how to solve this problem and any ideas to what I described above about the appending the name and the price?

thanks in advance! benji

What is the dataSource of your tableview? – PGDev Jun 28 '19 at 11:33 — PGDev, Jun 28 '19 at 11:33

Scriptable · Accepted Answer · 2019-06-28T12:02:35.267

1

The data that goes into the cell comes from the UITableViewDataSource delegate which you set. So you must already have access to this data.

Instead of trying to pull data from a UI element, pull it from the source.

You can either add this information in as each item is selected or use UITableView indexPathForSelectedRows to get a list of index paths of all selected items.

Then you just get the products at these indexes in your data source

Some guidance...

// top of class, as an example
var products: [Product]()
var selectedProducts: [Product]()

// later in your code somewhere, maybe on didSelectRow
let indexPaths = tableView.indexPathsForSelectedRows
selectedProducts = indexPaths.map { products[indexPath.row] }

// if you just need names
let names = selectedProducts.map { $0.name } 

// or a tuple, containing name and price
let data = selectedProducts.map { ($0.name, $0.price) }

// a better option might be a dictionary
var shoppingList = [String, Double]()
selectedProducts.map { shoppingList[$0.name] = $0.price }

edited Jun 28 '19 at 12:02

answered Jun 28 '19 at 11:33

Scriptable

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where and how do I define indexPathForSelectedRows? – BSM Jun 28 '19 at 11:47
its a property of UITableView, added a basic example in my answer – Scriptable Jun 28 '19 at 12:02
what is the difarance between indexPathsForSelectedRows and indexPathForSelectedRow? – BSM Jun 28 '19 at 12:11
and what is map? – BSM Jun 28 '19 at 12:11
and the selectedProducts need to be something what can be deleted afterword if pressed on a specific button, that possible when its inferring from the Products class? – BSM Jun 28 '19 at 12:13

score 1 · Answer 2 · answered Jun 28 '19 at 11:43

Instead of accessing the cell for data, you must use the tableView's dataSource for that.

If the model that you're using as your tableView's dataSource looks something like,

struct Product {
    var name: String
    var price: Double
}

Then, you can access the name and price of each product in tableView(_:didSelectRowAt:) like,

var products = [Product]() //use this as dataSource of the tableView
var names = [String]()
var prices = [Double]()

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    let product = self.products[indexPath.row]
    self.names.append(product.name)
    self.prices.append(product.price)
}

I am using a Realm DataBase, not a struct. so it might be different — BSM, Jun 28 '19 at 11:50

Is it posibble in Swift, to append a value of a UITableViewCell to a array of Strings?

2 Answers2