iOS Swift Radio Button

1.建立一個專案
2.建立兩個SSRadioButton.swift與SSRadioButtonsController.swift檔案

SSRadioButton.swift

//
//  SSRadioButton.swift
//  SampleProject
//
//  Created by Shamas on 18/05/2015.
//  Copyright (c) 2015 Al Shamas Tufail. All rights reserved.
//

import Foundation
import UIKit
@IBDesignable

class SSRadioButton: UIButton {
    
    private var circleLayer = CAShapeLayer()
    private var fillCircleLayer = CAShapeLayer()
    override var selected: Bool {
        didSet {
            toggleButon()
        }
    }
    /**
     Color of the radio button circle. Default value is UIColor red.
     */
    @IBInspectable var circleColor: UIColor = UIColor.redColor() {
        didSet {
            circleLayer.strokeColor = circleColor.CGColor
            self.toggleButon()
        }
    }
    /**
     Radius of RadioButton circle.
     */
    @IBInspectable var circleRadius: CGFloat = 5.0
    @IBInspectable var cornerRadius: CGFloat {
        get {
            return layer.cornerRadius
        }
        set {
            layer.cornerRadius = newValue
            layer.masksToBounds = newValue > 0
        }
    }
    
    private func circleFrame() -> CGRect {
        var circleFrame = CGRect(x: 0, y: 0, width: 2*circleRadius, height: 2*circleRadius)
        circleFrame.origin.x = 0 + circleLayer.lineWidth
        circleFrame.origin.y = bounds.height/2 - circleFrame.height/2
        return circleFrame
    }
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        initialize()
    }
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        initialize()
    }
    
    private func initialize() {
        circleLayer.frame = bounds
        circleLayer.lineWidth = 2
        circleLayer.fillColor = UIColor.clearColor().CGColor
        circleLayer.strokeColor = circleColor.CGColor
        layer.addSublayer(circleLayer)
        fillCircleLayer.frame = bounds
        fillCircleLayer.lineWidth = 2
        fillCircleLayer.fillColor = UIColor.clearColor().CGColor
        fillCircleLayer.strokeColor = UIColor.clearColor().CGColor
        layer.addSublayer(fillCircleLayer)
        self.titleEdgeInsets = UIEdgeInsetsMake(0, (4*circleRadius + 4*circleLayer.lineWidth), 0, 0)
        self.toggleButon()
    }
    /**
     Toggles selected state of the button.
     */
    func toggleButon() {
        if self.selected {
            fillCircleLayer.fillColor = circleColor.CGColor
        } else {
            fillCircleLayer.fillColor = UIColor.clearColor().CGColor
        }
    }
    
    private func circlePath() -> UIBezierPath {
        return UIBezierPath(ovalInRect: circleFrame())
    }
    
    private func fillCirclePath() -> UIBezierPath {
        return UIBezierPath(ovalInRect: CGRectInset(circleFrame(), 2, 2))
    }
    
    override func layoutSubviews() {
        super.layoutSubviews()
        circleLayer.frame = bounds
        circleLayer.path = circlePath().CGPath
        fillCircleLayer.frame = bounds
        fillCircleLayer.path = fillCirclePath().CGPath
        self.titleEdgeInsets = UIEdgeInsetsMake(0, (2*circleRadius + 4*circleLayer.lineWidth), 0, 0)
    }
    
    override func prepareForInterfaceBuilder() {
        initialize()
    }
}

SSRadioButtonsController.swift

//
//  RadioButtonsController.swift
//  TestApp
//
//  Created by Al Shamas Tufail on 24/03/2015.
//  Copyright (c) 2015 Al Shamas Tufail. All rights reserved.
//

import Foundation
import UIKit

/// RadioButtonControllerDelegate. Delegate optionally implements didSelectButton that receives selected button.
@objc protocol SSRadioButtonControllerDelegate {
    /**
     This function is called when a button is selected. If 'shouldLetDeSelect' is true, and a button is deselected, this function
     is called with a nil.
     
     */
    optional func didSelectButton(aButton: UIButton?)
}

class SSRadioButtonsController : NSObject
{
    private var buttonsArray = [UIButton]()
    private weak var currentSelectedButton:UIButton? = nil
    weak var delegate : SSRadioButtonControllerDelegate? = nil
    /**
     Set whether a selected radio button can be deselected or not. Default value is false.
     */
    var shouldLetDeSelect = false
    /**
     Variadic parameter init that accepts UIButtons.
     
     - parameter buttons: Buttons that should behave as Radio Buttons
     */
    init(buttons: UIButton...) {
        super.init()
        for aButton in buttons {
            aButton.addTarget(self, action: #selector(SSRadioButtonsController.pressed(_:)), forControlEvents: UIControlEvents.TouchUpInside)
        }
        self.buttonsArray = buttons
    }
    /**
     Add a UIButton to Controller
     
     - parameter button: Add the button to controller.
     */
    func addButton(aButton: UIButton) {
        buttonsArray.append(aButton)
        aButton.addTarget(self, action: #selector(SSRadioButtonsController.pressed(_:)), forControlEvents: UIControlEvents.TouchUpInside)
    }
    /**
     Remove a UIButton from controller.
     
     - parameter button: Button to be removed from controller.
     */
    func removeButton(aButton: UIButton) {
        let iteration = 0
        var iteratingButton: UIButton? = nil
        for i in iteration..<buttonsArray.count {
            iteratingButton = buttonsArray[i]
            if(iteratingButton == aButton) {
                break
            } else {
                iteratingButton = nil
            }
        }
        if(iteratingButton != nil) {
            buttonsArray.removeAtIndex(iteration)
            iteratingButton!.removeTarget(self, action: #selector(SSRadioButtonsController.pressed(_:)), forControlEvents: UIControlEvents.TouchUpInside)
            if currentSelectedButton == iteratingButton {
                currentSelectedButton = nil
            }
        }
    }
    /**
     Set an array of UIButons to behave as controller.
     
     - parameter buttonArray: Array of buttons
     */
    func setButtonsArray(aButtonsArray: [UIButton]) {
        for aButton in aButtonsArray {
            aButton.addTarget(self, action: #selector(SSRadioButtonsController.pressed(_:)), forControlEvents: UIControlEvents.TouchUpInside)
        }
        buttonsArray = aButtonsArray
    }
    
    func pressed(sender: UIButton) {
        if(sender.selected) {
            if shouldLetDeSelect {
                sender.selected = false
                currentSelectedButton = nil
            }
        } else {
            for aButton in buttonsArray {
                aButton.selected = false
            }
            sender.selected = true
            currentSelectedButton = sender
        }
        delegate?.didSelectButton?(currentSelectedButton)
    }
    /**
     Get the currently selected button.
     
     - returns: Currenlty selected button.
     */
    func selectedButton() -> UIButton? {
        return currentSelectedButton
    }
}

3.在Main.storyboard拉三個button

4.連結Button至ViewController.swift

5.選擇Buuton->點選Show the Identity inspector ->Class選SSRadioButton
方法一:點選+ 新增circleColor與circleRadius

方法二:點選Show the Attributes inspector會出現Radio Button 去設定

6.ViewController.swift

import UIKit

class ViewController: UIViewController, SSRadioButtonControllerDelegate  {

    @IBOutlet weak var bt1: UIButton!
    @IBOutlet weak var bt2: UIButton!
    @IBOutlet weak var bt3: UIButton!
    
    var radioButtonController: SSRadioButtonsController?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        radioButtonController = SSRadioButtonsController(buttons: bt1, bt2, bt3)
        radioButtonController!.delegate = self
        radioButtonController!.shouldLetDeSelect = true //true:點第二下取消 false:點第二下仍是選擇
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func didSelectButton(aButton: UIButton?) {
        let currentButton = radioButtonController!.selectedButton()!
        print("點選\(currentButton.currentTitle!)")
    }


}

檔案下載: https://github.com/terryyamg/Swift-RadioButtonTest
參考連結: https://github.com/shamasshahid/SSRadioButtonsController