Allow only one decimal in UITextField Class?

Question

I'm a beginner working on my own practice app. Trying to create a text field that only allows for one decimal place in a field where users are asked to input a price. Each time the function is accessed through my view controller the decimal counter remains at one and doesn't increment. the field will continue to accept decimal characters and the console repeatedly prints 1. Any insight would be greatly appreciated. (or likely there is a better solution that I am totally missing?)

import UIKit
import Foundation

class NumberValidator: UITextField {

    //MARK: Glabal Variables
    var decimalCounter = 0

    //MARK: Validate as numeric allowing decimal

    func validatePriceField(string: String) -> Bool {

        if ( string == "." && decimalCounter < 1 ) {
            decimalCounter++
            print("\(decimalCounter)")
        }

        if ( string == "." && decimalCounter >= 1 ) {
            return false
        }

        switch string {

        case "0","1","2","3","4","5","6","7","8","9":
            return true

        case ".":
            return true

        default:
            let array = Array(string.characters)
            if array.count == 0 {
                return true
            }
            return false
        }

    }

Answer 1 · 2015-12-11T20:41:00Z

December 11, 2015 8:41pm

I would keep track of the user input via

UITextFieldTextDidChangeNotification

Keep track of the string users have entered along the way and then prevent them from entering something you do not like.

I hope that helps,

Mike

PS: Thanks to the awesome resources on Team Treehouse, I just launched my first app.

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Nicholas Kennedy

Nicholas Kennedy

Allow only one decimal in UITextField Class?

Jhoan Arango

Jhoan Arango

Nicholas Kennedy

Nicholas Kennedy

1 Answer

Michael Reining

Michael Reining

Jhoan Arango

Jhoan Arango