danielcardonarojas/veil

A flexible string masking and formatting library

Veil

Easy and flexible string masking utility.

Features

• Platform independent (this is a pure swift package)
• Provides masked and unmasked input (process method).
• Easy integration to (UIKit, SwiftUI)
• Input blocking comes free.

Installation

Veil comes with support for SwiftPM so just copy this repos url into your Xcode project

Usage

Veil enables string masking by providing a pattern of special characters

To create for instance a date formatter for mm / yy this is as simple as:

let dateMask = Veil(pattern: "## / ##")
let result = dateMask.mask(input: "234")
// result = "23 / 4"

Veil uses a configuration object to specify how to parse the mask pattern. The default configuration uses # to represent any digit and * to represent other characters.

Also notice that Veil will pickup any other character such as / and spaces as symbols in the pattern and will insert them automatically in the resulting string.

UITextField integration

UITextField integration is simple and doesn't require usage of its delegate.

This how you can accomplish live masking of textfields.

let dateMask = Veil(pattern: "## / ##")

@objc func textDidChange(_ sender: UITextField) {
    guard let currentText = sender.text else  {
        return
    }

    sender.text = dateMask.mask(input: currentText, exhaustive: false)
}

When performing masking of live input just make sure to use the exhaustive option set to false

veil's Issues

SwiftUI

Is there a sample for SwiftUI?
I write like this, but clearing characters requires clearing mask characters too

@Published var myText = "" {
        didSet {
            if myText != myMask.mask(input: myText, exhaustive: false) {
                myText = myMask.mask(input: myText, exhaustive: false)
            }
        }
    }

Cursor move to the trailing of the masked text.

Hello 👋🏼

I tried to use Veil to format credit card numbers of 16 digits within a text field. I'm using the pattern of "#### #### #### ####".

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
     
      let numberMask = Veil(pattern: "#### #### #### ####")
           
      textField.text = numberMask.mask(input: cardNumber, exhaustive: false)

}

The formatting works fine, but when I tried to move the cursor in the middle of the text and delete a number, the cursor move automatically to the last number. (see the video attached)

In my opinion, the cursor should stay at the same place where the deletion happened.

Thank you.

mask_issue.mov

Masking for Letters

Is there a way to extend veil to limit the * pattern for letters only?