I have a tableview cells, and the titles I get from server. Titles are array of strings. The data is drawing like this

• All data
• List item
• Coffees
• Teas
• Dessert
• Main dishes

when I click on each of these I can easily select them and deselect, that part works perfect. Now i want that when i select List item, Coffees, teas, dessert, main dishes together, these 5 items will be deselected and all data(first cell) will be selected automatically. I know i should write this in didselect method, only i dont know how to write logic correctly. Please help me to solve this. Thanks

this is my code example

 func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        guard let isSelected = arrayOfTitles[indexPath.row].isSelected else {arrayOfTitles[indexPath.row].isSelected = true; return}
        arrayOfTitles[indexPath.row].isSelected = !isSelected
        filter?.values?[indexPath.row].isSelected = !isSelected
        for i in 1..<arrayOfTitles.count {
            if arrayOfTitles[i].isSelected == isSelected {
                arrayOfTitles[0].isSelected = isSelected
                arrayOfTitles[i].isSelected = !isSelected
            }
        }
    }

CodePudding user response：

You can try

 func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        guard let isSelected = arrayOfTitles[indexPath.row].isSelected else {arrayOfTitles[indexPath.row].isSelected = true; return}
        arrayOfTitles[indexPath.row].isSelected = !isSelected
        filter?.values?[indexPath.row].isSelected = !isSelected
        let allSelected = arrayOfTitles[1...].filter { $0.isSelected }
        if allSelected.count == arrayOfTitles.count - 1 {
           arrayOfTitles[0].isSelected = true
            (1..<arrayOfTitles.count).forEach { arrayOfTitles[$0].isSelected = false }
        }
}

CodePudding user response：

Because a table view maintains its own array of selected rows (IndexPaths), you don't really need to maintain a separate .isSelected property on your data. If you need it (for state persistence, for example), you can always grab the selected rows when needed.

So, here's another approach...

I'm guessing that if you have some of the rows selected, and you then select the top row, you would also want to deselect the other rows:

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    
    var arrayOfTitles: [String] = [
        "All data",
        "List Item",
        "Coffees",
        "Teas",
        "Dessert",
        "Main dishes",
    ]
    
    let tableView = UITableView()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        tableView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(tableView)
        
        let g = view.safeAreaLayoutGuide
        NSLayoutConstraint.activate([
            tableView.topAnchor.constraint(equalTo: g.topAnchor, constant: 20.0),
            tableView.leadingAnchor.constraint(equalTo: g.leadingAnchor, constant: 20.0),
            tableView.trailingAnchor.constraint(equalTo: g.trailingAnchor, constant: -20.0),
            tableView.bottomAnchor.constraint(equalTo: g.bottomAnchor, constant: -20.0),
        ])
        
        tableView.register(UITableViewCell.self, forCellReuseIdentifier: "c")
        tableView.dataSource = self
        tableView.delegate = self
        
        tableView.allowsMultipleSelection = true
    }
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return arrayOfTitles.count
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let c = tableView.dequeueReusableCell(withIdentifier: "c", for: indexPath)
        c.textLabel?.text = arrayOfTitles[indexPath.row]
        return c
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        // ignore if nothing is selected
        guard let paths = tableView.indexPathsForSelectedRows else { return }
        
        // if we selected the top row ("All data"), deselect the others
        if indexPath.row == 0 {
            // deselect the other rows
            paths.forEach {
                if $0.row != 0 {
                    tableView.deselectRow(at: $0, animated: true)
                }
            }
        } else {
            // get the selected rows as a sorted array of Int
            let rows: [Int] = (paths.map { $0.row }).sorted()
            // Int array of rows 1 thru 5
            let myFiveRows: [Int] = Array(1...5)
            // if the two arrays are equal (they're both [1,2,3,4,5])
            if rows == myFiveRows {
                // deselect all
                tableView.selectRow(at: nil, animated: true, scrollPosition: .none)
                // select the top row
                tableView.selectRow(at: IndexPath(row: 0, section: 0), animated: true, scrollPosition: .none)
            }
        }
    }

}