tableView.reloadData（）表未更新

Question

The table does not display the updated array to return to the cell. When I launch the app I get blank cells. All permissions have been given in the storyboard. I tried the tableView.reloadData() everywhere but can't seem to make it work either. If anyone can explain where Im going wrong that would really help me get better.

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

@IBOutlet weak var slider: UISlider!

@IBAction func sliderSelector(_ sender: Any) {
    tableGenerate()
}

var arrayTable = [Int]()

public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return arrayTable.count
}

public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = UITableViewCell(style:UITableViewCellStyle.default, reuseIdentifier: "Cell")
    cell.textLabel?.text = String(arrayTable[indexPath.row])
    tableView.reloadData()
    return cell
}

func tableGenerate () {
    var tableMultiplier = 1
    while tableMultiplier <= 50 {
        arrayTable.append(tableMultiplier * Int(slider.value))
        tableMultiplier += 1
        print(arrayTable)
    }
}

Answer 1

Add outlet of tableview like this and connect with table in storyboard-

@IBOutlet weak var tableView1: UITableView!

Change code to this -

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

@IBOutlet weak var slider: UISlider!
@IBOutlet weak var tableView1: UITableView!

@IBAction func sliderSelector(_ sender: Any) {
    tableGenerate()
}

var arrayTable = [Int]()

public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return arrayTable.count
}

public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

    let cell = UITableViewCell(style:UITableViewCellStyle.default, reuseIdentifier: "Cell")
    cell.textLabel?.text = String(arrayTable[indexPath.row])
    return cell
}

func tableGenerate () {
    var tableMultiplier = 1
    while tableMultiplier <= 50 {
        arrayTable.append(tableMultiplier * Int(slider.value))
        tableMultiplier += 1
    }
        print(arrayTable)
    tableView1.reloadData()

}

Answer 2

By calling tableView.reloadData() inside cellForRowAt , you create an infinite loop, since reloadData() automatically calls cellForRowAt . You need to move reloadData() inside tableGenerate() , since it should only be called when your data source is changed.

You also need to create an IBOutlet for your tableView in Storyboard . Since you are not using a UITableViewController , you need to do this manually.

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    @IBOutlet weak var tableView: UITableView!
    @IBOutlet weak var slider: UISlider!

    @IBAction func sliderSelector(_ sender: Any) {
        tableGenerate()
    }

    var arrayTable = [Int]()

    public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return arrayTable.count
    }

    public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(style:UITableViewCellStyle.default, reuseIdentifier: "Cell")
        cell.textLabel?.text = String(arrayTable[indexPath.row])
        return cell
    }

    func tableGenerate () {
        var tableMultiplier = 1
        while tableMultiplier <= 50 {
            arrayTable.append(tableMultiplier * Int(slider.value))
            tableMultiplier += 1
            print(arrayTable)
        }
        tableView.reloadData()
    }
}

Answer 3

forgot to create the table outlet ! I also forgot to reset the array with the array slider with arrayTable = [] now it works fine