A UILabel subclass that adds a typewriting animation effect - as if a 👻 was typing it directly on your user's device!

GhostTypewriter was inspired by the following post here.

Installation

CocoaPods

To integrate GhostTypewriter into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '10.0'

pod 'GhostTypewriter'

Then, run the following command:

$ pod install

CocoaPods 1.1.1+ is required to build GhostTypewriter.

Swift Package Manager

Swift Package Manager is a dependency manager built into Xcode.

If you are using Xcode 11 or higher, go to File -> Add Packages... and enter package repository URL https://github.com/wibosco/GhostTypewriter into the search bar, then follow the instructions.

Usage

TypewriterLabel is a subclass of UILabel and where the animation (magic) happens. It works by taking advantage of the attributedText property on the label and changing the properties of the text content to gradually expose the text using an animation similar to what you get on a mechanical typewriter.

A TypewriterLabel instance when added as a subview will hide it's content.

Starting

Starting the animation will cause the content of the label to be reveal one character at a time.

How quickly each character is revealed is controlled by setting the typingTimeInterval property.

There are two ways to start an animation: with and without a completion closure.

With a completion closure:

import GhostTypewriter

@IBAction func startAnimationButtonPressed(_ sender: Any) {
    titleLabel.startTypewritingAnimation {
        //Implement your completion closure body here...
    }
}

Without a completion closure:

import GhostTypewriter

@IBAction func startAnimationButtonPressed(_ sender: Any) {
    titleLabel.startTypewritingAnimation()
}

Stopping

Stopping an animation causes the characters that have been revealed to remain as is and no new characters being revealed.

import GhostTypewriter

@IBAction func stopAnimationButtonPressed(_ sender: Any) {
    titleLabel.stopTypewritingAnimation()
}

Resetting

Resetting an animation causes all characters to be hidden.

import GhostTypewriter

@IBAction func resetAnimationButtonPressed(_ sender: Any) {
    titleLabel.resetTypewritingAnimation()
}

It's important to note that resetting an TypewriterLabel instance does not cause the animation to restart instead you need to call restartTypewritingAnimation().

Restarting

Restarting an animation causes all characters to be hidden and for the animation to begin from the start again.

There are two ways to start an animation: with and without a completion closure.

Without a completion closure:

import GhostTypewriter

@IBAction func restartAnimationButtonPressed(_ sender: Any) {
    titleLabel.restartTypewritingAnimation()
}

With a completion closure:

import GhostTypewriter

@IBAction func restartAnimationButtonPressed(_ sender: Any) {
    titleLabel.restartTypewritingAnimation {
        //Implement your completion closure body here...
    }
}

Completing

Completing an animation causes all characters to instantly be revealed.

import GhostTypewriter

@IBAction func completeAnimationButtonPressed(_ sender: Any) {
    titleLabel.completeTypewritingAnimation()
}

Animation Options

Style

By default TypewriterLabel reveals the content as it animates however this can be changed to hiding the content by setting the animationStyle property to .hide:

import GhostTypewriter

override func viewDidLoad() {
    super.viewDidLoad()

    titleLabel.animationStyle = .hide
}

animationStyle is defaulted to .reveal

Direction

By default TypewriterLabel animates from character index 0 to n-1 however this can be changed to go from charcter index n-1 to 0 by setting the animationDirection to .backward:

import GhostTypewriter

override func viewDidLoad() {
    super.viewDidLoad()

    titleLabel.animationDirection = .backward
}

animationDirection is defaulted to .forward.

Adjusting Animation Timing

Each character of a TypewriterLabel instance is revealed at a pace set by the typingTimeInterval property.

typingTimeInterval defaults to 0.1 second.

import GhostTypewriter

override func viewDidLoad() {
    super.viewDidLoad()

    titleLabel.typingTimeInterval = 0.3
}

It's important to note that setting/changing typingTimeInterval after an animation has been started, has no affect on the timing of that animation.

Storyboards

As TypewriterLabel is contained in a pod, when using it with storyboards you will need to set the Module field to GhostTypewriter.

Migrating from v1 to v2

Version 2.0.0 of GhostTypewriter contains breaking changes.

• cancelTypewritingAnimation() now use resetTypewritingAnimation().
• cancelTypewritingAnimation(clearText: true) now use resetTypewritingAnimation().
• cancelTypewritingAnimation(clearText: false) now use stopTypewritingAnimation().

Example

GhostTypewriter comes with an example project to provide more details than listed above.

Found an issue?

Please open a new Issue here if you run into a problem specific to GhostTypewriterLabel, have a feature request, or want to share a comment.

Pull requests are encouraged and greatly appreciated! Please try to maintain consistency with the existing code style. If you're considering taking on significant changes or additions to the project, please communicate in advance by opening a new Issue. This allows everyone to get onboard with upcoming changes, ensures that changes align with the project's design philosophy, and avoids duplicated work.