NumberFormatter Argument labels '(_:)' do not match any available overloads

Question

Following this line

 lable2xValue.text = numberFormatter.string(from: value)

First it is throwing this error

Cannot convert value of type 'Double' to expected argument type 'NSNumber'

Then Xcode suggest value replace with NSNumber

 lable2xValue.text = numberFormatter.string(from: NSNumber(value))

When I do that then this error showing

Argument labels '(_:)' do not match any available overloads

Here is my full code

   //computed property
    var value2x : Double? {
        if let  value = value1x{
            return (value * 2)
        }
        else{
            return nil
        }
    }
  //objerver       
    var value1x : Double? {
        didSet{
            updateLabel2xValue()
        }
    }

    func updateLabel2xValue(){

        if let value = value2x {
            //lable2xValue.text = "\(value)"


            //MARK:- ERORR Cannot convert value of type 'Double' to expected argument type 'NSNumber'
            //lable2xValue.text = numberFormatter.string(from: value)

            //MARK:- ERROR Argument labels '(_:)' do not match any available overloads
            lable2xValue.text = numberFormatter.string(from: NSNumber(value))

        }
        else {
            lable2xValue.text = "???"
        }

    }

    var  numberFormatter : NumberFormatter = {
        let ls = NumberFormatter()
        ls.numberStyle = .decimal
        ls.minimumFractionDigits = 0
        ls.maximumFractionDigits = 2
        return ls
    }()


    @IBAction func textField1xValueEditingChange(_ sender: AnyObject) {
        //print(self.textField1xValue.text)
        if let value = self.textField1xValue.text , let doubleValue = Double(value){
            value1x = doubleValue

        }else{
            value1x = nil
        }
    }

Note : if I am trying this way then it is working fine

lable2xValue.text = numberFormatter.string(from: 50.33)

Answer 1

The compiler wants

numberFormatter.string(from: NSNumber(value:value))

unfortunately it doesn't suggest that.

A quick hint: ⌘-click on NSNumber to see the available initializers in the declaration file.

---

Alternatively in the current version of Swift in Xcode 8.1 you can also bridge cast Double to NSNumber

numberFormatter.string(from: value as NSNumber)

Answer 2

You need to add first parameter label value with init of NSNumber.

lable2xValue.text = numberFormatter.string(from: NSNumber(value: value))