BLACK FRIDAY SALE: Save 50% on all my Swift books and bundles! >>

How to create custom text input using UIKeyInput

Swift version: 5.6

Paul Hudson    @twostraws   

Although we can use pressesBegan() and pressesEnded() to read keypresses, they won’t show the on-screen keyboard and so won’t let you provide custom text input for users without a hardware keyboard. If you need that keyboard to be shown, you should create a class that adopts the UIKeyInput protocol instead, which has just three requirements:

  • What to do when text is inserted.
  • What to do when text is deleted.
  • Whether your custom text input currently has text or not.

The only other thing you need to know is that your custom input control will show the keyboard when it becomes first responder. So, you should override the canBecomeFirstResponder property of your subclass, setting it to true rather than the default of false.

To demonstrate this, we could create a simple UIView subclass that draws text to the screen as it’s typed, like this:

class TextRenderingView: UIView, UIKeyInput {
    // the string we'll be drawing
    var input = ""

    override var canBecomeFirstResponder: Bool {

    var hasText: Bool {
        input.isEmpty == false

    func insertText(_ text: String) {
        input += text

    func deleteBackward() {
        _ = input.popLast()

    override func draw(_ rect: CGRect) {
        let attrs: [NSAttributedString.Key: Any] = [.font: UIFont.systemFont(ofSize: 32)]
        let attributedString = NSAttributedString(string: input, attributes: attrs)
        attributedString.draw(in: rect)

If you want to handle more complex user input, such as selecting ranges of text or drawing the caret, you should use the more advanced UITextInput protocol instead.

Save 50% in my Black Friday sale.

SAVE 50% To celebrate Black Friday, all our books and bundles are half price, so you can take your Swift knowledge further without spending big! Get the Swift Power Pack to build your iOS career faster, get the Swift Platform Pack to builds apps for macOS, watchOS, and beyond, or get the Swift Plus Pack to learn advanced design patterns, testing skills, and more.

Save 50% on all our books and bundles!

Sponsor Hacking with Swift and reach the world's largest Swift community!

Available from iOS 3.2

Similar solutions…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let us know!

Average rating: 3.9/5

Unknown user

You are not logged in

Log in or create account

Link copied to your pasteboard.