WASHD - What Apple Should Have Done

##The easiest way to add validation, text filtering, max length, and text field order to your UITextFields

###The best part is that you don't have to subclass UITextField--this is made using extensions

Requirements

ARC
iOS 8

Installation

WASHD is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod "WASHD"

##Usage ###Interface Builder

##Required Code To Support UITextField "jump order"

override func viewDidLoad() {
    super.viewDidLoad()
    self.findAllTextInputs() //find all text inputs in the view controller for jump order process
}

func textFieldDidBeginEditing(textField: UITextField) {
    self.currentjumpOrder = textField.jumpOrder //set current jump order
}
    
func textFieldShouldReturn(textField: UITextField) -> Bool {
    self.moveNext() //move to the next text input in order
    return true
}

"Jump Order" refers to the order in which UITextFields will be given first responder on press of the "Return" button (like tab order in web development)

Jump Order also works on UITextView 👊

To support max length, text filtering, and text formatting

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
    if textField.reachedMaxLength(range, string: string) || !string.shouldAllow(textField.allowedCharacters){
        return false
    }
    return textField.formatText(string)
}

Even if you haven't set a format on a UITextField, you can still use "textField.formatText(string)". It will simply return true.

To validate before form submission (test every UITextField you want validated)

let result = txtCreditCard.validate() //returns ValidationResult (see below)
if result.isValid
{
  print(result.transformedString)
}
else
{
  print(result.failureMessage)
}

#That's it!

Validation Result

class ValidationResult
{
    var isValid = false
    var failureMessage : String? = nil
    var transformedString : String = ""
    //...
}

Built-in validation types

    case None = -1
    case Zip = 0
    case StreetAddress = 1
    case Phone = 2
    case Email = 3
    case IPAddress = 4
    case MACAddress = 5
    case GPSCoordinate = 6
    case GPSPoint = 7
    case URL = 8
    case CreditCard = 9
    case Money = 10
    case Letters = 11
    case LettersWithSpaces = 12
    case AlphaNumeric = 13
    case AlphaNumericWithSpaces = 14
    case PositiveNumbers = 15
    case NegativeNumbers = 16
    case WholeNumbers = 17
    case PositiveFloats = 18
    case NegativeFloats = 19
    case Floats = 20
    case Text = 21
    case SSN = 22
    case States = 23
    case Name = 24

###You can also set everything up programatically

txtCreditCard.validationType = .CreditCard
txtCreditCard.format = "xxxx xxxx xxxx xxxx"
txtCreditCard.maxLength = 19
txtCreditCard.jumpOrder = 1

#Individual Enchancement Breakdown

##Supporting Max Length

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool 
{
  if textField.reachedMaxLength(range, string: string)
    return false
  }
  return true
}

##Filtering UITextField

###It's built in if you use validation!

(e.g. a textfield with a validationType set to ".Zip" (i.e. txtZip.validationType = .Zip) will get have txtZip.allowedCharacters set to the Zip constant below)

Simply add this code to the "...shouldChangeCharactersInRange..." UITextField delegate method...

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool 
{
  if !string.shouldAllow(textField.allowedCharacters)
    return false
  }
  return true
}

UITextField predefined strings

let UpperCaseLetters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
let LowerCaseLetters = "abcdefghijklmnopqrstuvwxyz"
let AllLetters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
let UpperCaseHex = "0123456789ABCDEF"
let LowerCaseHex = "0123456789abcdef"
let AllHex = "0123456789abcdefABCDEF"
let PositiveWholeNumbers = "0123456789"
let WholeNumbers = "-0123456789"
let PositiveFloats = "0123456789."
let Floats = "-0123456789."
let Email = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_-+@.%"
let Street = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 -#.&"
let IPAddress = "0123456789."
let Money = "0123456789.$"
let Phone = "0123456789.()- "
let Zip = "0123456789-“

###Alternatively, you can add your own using "shouldAllow(String...)"

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool 
{
  return string.shouldAllow(Numbers, "@#$") // you can enter several different strings of characters to allow
}

##Validation

###Declare your own — simple expression...

let zip = ValidationExpression(expression: "^\\d{5}(-\\d{4})?$", description: "Zip Code",failureDescription: "Invalid Zip Code”)

…and apply it to a UITextField programmatically

txtZip.validationExpression = zip

###More advanced validation

adds sub-rules for more user friendly hints on how to fix a problem
text transformation / cleaning (Transformation is done BEFORE validation and is optional)

let zip = ValidationExpression(expression: "^\\d{5}(-\\d{4})?$", description: "Zip Code",failureDescription: "Invalid Zip Code", hints: [
  ValidationRule(priority: 1, expression: "\\d{5}", failureDescription: "Zip code must be 5 characters"),
  ValidationRule(priority: 0, expression: "[0-9]+", failureDescription: "Not numbers"),
  ],transformText: 
    { (zipcode) in
      var myString = zipcode
      myString = myString?.stringByReplacingOccurrencesOfString(" ", withString: "")
      return myString!
    }
  ,furtherValidation:nil)

###Most advanced

hints
input text transformation
further validation

4242 4242 4242 4243 is a credit card number that passes the regular expression check. However, the further validation performs a Luhn check that all credit cards must pass (you can read more here: (https://en.wikipedia.org/wiki/Luhn_algorithm).

The furtherValidation closure has the transformed text as a parameter and returns a Validation Result object

NOTE condensedWhitespace is a helper variable that gets rid of multiple side-by-side spaces in case a user mistypes into the field in IB

let creditCard = ValidationExpression(expression: "^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6(?:011|5[0-9][0-9])[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|(?:2131|1800|35\\d{3})\\d{11})$",
            description: "Debit or Credit Card",
            failureDescription: "Invalid card",
            hints: [ValidationRule(priority: 0, expression: "\\d+", failureDescription: "Missing Numbers")],
            transformText:
            { (card) in
                var myString = card
                myString = myString?.condensedWhitespace.stringByReplacingOccurrencesOfString(" ", withString: "") 
                return myString!
            },
            furtherValidation:{[weak self] (card) in
            if (self?.luhnTest(card))!
            {
                return ValidationResult(isValid: true, failureMessage: nil, transformedString: card)
            }
            else
            {
                return ValidationResult(isValid: false, failureMessage: "Card failed Luhn check", transformedString: card)
            }
})

func luhnTest(number: String) -> Bool
{
    let noSpaceNum = number.condensedWhitespace
    let reversedInts = noSpaceNum.characters.reverse().map{
        Int(String($0))
    }
    return reversedInts.enumerate().reduce(0, combine: {(sum, val) in let odd = val.index % 2 == 1
        return sum + (odd ? (val.element! == 9 ? 9 : (val.element! * 2) % 9) : val.element!)
    }) % 10 == 0
}

##TODOs

Add character filtering
Add more useful hints for several validationTypes
Update code to Swift 3

###Please feel free to make a pull request and add more commonly-used validations

Example

To run the example project, clone the repo, and run pod install from the Example directory first.

Authors

Ian Howerton and Andrew Goodwin, andrewggoodwin@gmail.com

License