CODEWITHSUNDEEP
uitableviewswift5
Florentin Lupascu
Florentin Lupascu

Reputation: 993

How to send data from UITableViewCell to ViewController in Swift 5

I have one UISlider and one UILabel. I want to reflect the value from that UISlider to my UILabel. I have a UITableViewCell where I have both outlets and I have a ViewController where I connected the Slider and I create an action function (ValueChanged). I did the logic in that function but is not working because is saying that my outlet is NIL. Can anyone help me to pass this data correctly ? Maybe can be done with Delegates but I don't know how more exactly.

Here is my code for UITableViewCell:

import UIKit

class SliderCell: UITableViewCell {

    // Interface Links
    @IBOutlet weak var slider: UISlider!
    @IBOutlet weak var progressLabel: UILabel!

    override func awakeFromNib() {
        super.awakeFromNib()
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)
    }
}

And here is the Controller:

import UIKit

// Table View with Dynamic Cells
class MainViewController: UITableViewController {

    var sliderCell: SliderCell!

    override func viewDidLoad() {
        super.viewDidLoad()

        sliderCell = SliderCell()
    }

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

        switch indexPath.row {
        // Row 0  -  My Slider
        case 0:
            let cell = tableView.dequeueReusableCell(withIdentifier: "sliderCell", for: indexPath) as! SliderCell
            return cell
        default:
            return UITableViewCell()
        }
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 1
    }

    override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

        // Set the height for slider cell to 200 pixels
        switch indexPath.row {
        case 0:
            return 200
        default:
            return 200
        }
    }

    // Reflect the value of Slider to ProgressLabel
    @IBAction func sliderValueChanged(_ sender: UISlider) {

        var currentValue = Int(sender.value)
        let stepSize:Int = 10
        currentValue = (currentValue - currentValue % stepSize)
        DispatchQueue.main.async {
            self.sliderCell.progressLabel.text = "\(currentValue)%"
        }
    }
}

Thanks in advance if you are reading this !

Upvotes: 0

Views: 335

Answers (1)

Shehata Gamal
Shehata Gamal

Reputation: 100503

Don't add a reference to your cell here

sliderCell = SliderCell()

but use a delegate in cellForRowAt like

  let cell = 
  cell.delegate = self

then inside the cell send anything with

delegate?.sendSliderValue()

you can also add slider action implementation inside the vc like

let cell = //
cell.slider.addTarget ////
cell.slider.tag = indexPath.row

 @objc func sliderChanged(_ slider:UISlider) { 
     print(slider.value,slider.tag)
     if let cell = tableView.cellForRow(at:IndexPath(row:slider.tag,section:0)) as? SliderCell {
         var currentValue = Int(sender.value)
         let stepSize:Int = 10
         currentValue = (currentValue - currentValue % stepSize)
         cell.progressLabel.text = "\(currentValue)"
     }

     // or 

     if let cell = tableView.visibleCells.first as? SliderCell {
       //////
     }
 }

Upvotes: 1

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