Slightly inspired by Google's material radio button.

The clip below has 3 sections: full speed, 25% and 10%, but after converting it to GIF, it actually made it longer, so the 10% part takes a really long time. Here's an mp4 link; try with Chrome if Safari doesn't work - for me it doesn't.

CocoaPods is a dependency manager for Cocoa projects. You can install it with the following terminal command:

gem install cocoapods

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

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '9.0'
use_frameworks!

target '<Your Target Name>' do
  pod 'LTHRadioButton'
end

Then, run the following terminal command:

pod install

Drag LTHRadioButton.swift from the source folder into your Xcode project.

The initializer takes up to 3 params: a diameter, a selectedColor, and a deselectedColor. All of them are optional:

• diameter defaults to 18
• selectedColor defaults to a light blue
• deselectedColor defaults to UIColor.lightGray

It doesn't use Auto Layout internally, but after initialization it will have a proper size, so you can simply create constraints based on its frame.width and frame.height.

selectedColor and deselectedColor have been made publicly customizable for cases like a tableView with alternating row and radio colors, where the tableView might dequeue a cell with one color for displaying a cell with a different color.

isSelected - Indicates whether the radio button is selected.

useTapGestureRecognizer - Indicates whether a tap gesture recognizer should be added to the control when setting callbacks. This defaults to true just so that onSelect and onDeselect can add the gesture recognizer automatically, but the recognizer is not added by default.

• Settings this to true will also add the required UITapGestureRecognizer if needed.
• Settings this to false will also remove the UITapGestureRecognizer if it was previously added.

init(diameter: CGFloat = 18, selectedColor: UIColor? = nil, deselectedColor: UIColor? = nil) // Colors default internally if nil.
func select(animated: Bool = true) // Selects the radio button.
func deselect(animated: Bool = true) // Deselects the radio button.

You can make use of the onSelect and onDeselect methods to add closures to be run when selecting/deselecting the control. Since these closures make most sense for taps and because there are no recognizers by default, these methods will also add one (and only one) UITapGestureRecognizer to the control to handle the taps; the closure calls happen right as the animations begin.

If you'd like to use the callbacks but don't need the tap gesture recognizer, you can set useTapGestureRecognizer to false.

let radioButton = LTHRadioButton(selectedColor: .red)
container.addSubview(radioButton)

radioButton.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
  radioButton.centerYAnchor.constraint(equalTo: container.centerYAnchor),
  radioButton.leadingAnchor.constraint(equalTo: container.leadingAnchor, constant: 16),
  radioButton.heightAnchor.constraint(equalToConstant: radioButton.frame.height),
  radioButton.widthAnchor.constraint(equalToConstant: radioButton.frame.width)]
)

radioButton.onSelect {
  print("I'm selected.")
}

radioButton.onDeselect {
  print("I'm deselected.")
}

[...]

radioButton.select() // I'm selected.

[...]

radioButton.deselect(animated: false) // I'm deselected.

If you're using this control, I'd love hearing from you!

Licensed under MIT. If you'd like (or need) a license without attribution, don't hesitate to contact me.