UIButton various click events encapsulation, event response area modification, text image position (vertical center, horizontal center)

import Foundation
import UIKit

// MARK: - Click event closure and expand click range
typealias BtnAction = (UIButton) - > ()extension UIButton{
    private struct AssociatedKeys{
        static var actionKey = "actionKey"
    }
    
    @objc dynamic var action: BtnAction? {
        set{
            objc_setAssociatedObject(self.&AssociatedKeys.actionKey, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_COPY)}get{
            if let action = objc_getAssociatedObject(self.&AssociatedKeys.actionKey) as? BtnAction{
                return action
            }
            return nil}}/// Add a click event
    /// -parameter action: closure to execute when clicked
    @discardableResult // Remove the warning when the return value is not used
    func addClickAction(action:@escaping BtnAction) -> UIButton {
        return self.addEvent(event: .touchUpInside, action: action)
    }
    
    
    /// Add an event
    /// - Parameters:
    /// - event: indicates the added event
    /// -action: closure to execute in event response
    @discardableResult // Remove the warning when the return value is not used
    func addEvent(event:UIControl.Event.action:@escaping  BtnAction ) -> UIButton{
        self.action = action
        self.addTarget(self, action: #selector(touchUpInSideBtnAction), for: event)
        return self
    }

    @objc func touchUpInSideBtnAction(btn: UIButton) {
         if let action = self.action {
             action(btn)
         }
    }
    
    
    @discardableResult // Remove the warning when the return value is not used
    func addCountdown(time:Int.endAction:@escaping() - > ()) -> UIButton {
        // Countdown time
        var timeout = time
        let queue:DispatchQueue = DispatchQueue.global(qos: DispatchQoS.QoSClass.default)
        let _timer:DispatchSource = DispatchSource.makeTimerSource(flags: [], queue: queue) as! DispatchSource
        _timer.schedule(wallDeadline: DispatchWallTime.now(), repeating: .seconds(1))
        // execute every second
        _timer.setEventHandler(handler: { () -> Void in
            if(timeout< =0) {// The timer is closed
                _timer.cancel();
                DispatchQueue.main.sync(execute: { () -> Void in
                    self.isEnabled = true
                    endAction()
                })
            }else{// Counting down
                let seconds = timeout
                DispatchQueue.main.sync(execute: { () -> Void in
                    let str = String(describing: seconds)
                    let s = "Seconds"
                    self.titleLabel?.text = "\(str)\(s)"
                    self.setTitle("\(str)\(s)", for: .normal)
                    self.isEnabled = false
                })
                timeout - = 1;
            }
        })
        _timer.resume()
        return self
    }
    
    
    //
    private struct RuntimeKey {
        static let clickEdgeInsets = UnsafeRawPointer.init(bitPattern: "clickEdgeInsets".hashValue)
        / / /... Other Key statements
    }
    /// Need to expand the click margin
    public var addClickEdgeInsets: UIEdgeInsets? {
        set {
            objc_setAssociatedObject(self.UIButton.RuntimeKey.clickEdgeInsets!, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_COPY)}get {
            return objc_getAssociatedObject(self.UIButton.RuntimeKey.clickEdgeInsets!) as? UIEdgeInsets ?? UIEdgeInsets.zero
        }
    }
    // Rewrite the system method to modify the click area
    open override func point(inside point: CGPoint.with event: UIEvent?). -> Bool {
        super.point(inside: point, with: event)
        var bounds = self.bounds
        if (addClickEdgeInsets ! = nil) {
            let x: CGFloat = -(addClickEdgeInsets?.left ?? 0)
            let y: CGFloat = -(addClickEdgeInsets?.top ?? 0)
            let width: CGFloat = bounds.width + (addClickEdgeInsets?.left ?? 0) + (addClickEdgeInsets?.right ?? 0)
            let height: CGFloat = bounds.height + (addClickEdgeInsets?.top ?? 0) + (addClickEdgeInsets?.bottom ?? 0)
            bounds = CGRect(x: x, y: y, width: width, height: height) // A negative value is the method response range
        }
        return bounds.contains(point)
    }
    
    
}


// MARK: - Image text position
extension UIButton{
    
    enum RGButtonImagePosition {
        case top          // Picture on top, text on bottom, vertically centered
        case bottom       // Image at bottom, text at top, vertically centered
        case left         // Image on the left, text on the right, horizontally centered
        case right        // Image on the right, text on the left, horizontally centered
    }
    
    
    /// -description sets the position of the Button image
    /// - Parameters:
    /// - style
    /// -spacing: Spacing between button images and text
    func imagePosition(style: RGButtonImagePosition.spacing: CGFloat) {
        // Get the width and height of the imageView and titleLabel
        let imageWidth = self.imageView?.frame.size.width
        let imageHeight = self.imageView?.frame.size.height
        var labelWidth: CGFloat! = 0.0
        var labelHeight: CGFloat! = 0.0
        labelWidth = self.titleLabel?.intrinsicContentSize.width
        labelHeight = self.titleLabel?.intrinsicContentSize.height
        // Initialize imageEdgeInsets and labelEdgeInsets
        var imageEdgeInsets = UIEdgeInsets.zero
        var labelEdgeInsets = UIEdgeInsets.zero
        // Get imageEdgeInsets and labelEdgeInsets based on style and space
        switch style {
        case .top:
            // Up, left, down, right
            imageEdgeInsets = UIEdgeInsets(top: -labelHeight-spacing/2, left: 0, bottom: 0, right: -labelWidth)
            labelEdgeInsets = UIEdgeInsets(top: 0, left: -imageWidth!, bottom: -imageHeight! -spacing/2, right: 0)
            break;
        case .left:
            imageEdgeInsets = UIEdgeInsets(top: 0, left: -spacing/2, bottom: 0, right: spacing)
            labelEdgeInsets = UIEdgeInsets(top: 0, left: spacing/2, bottom: 0, right: -spacing/2)
            break;
        case .bottom:
            imageEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: -labelHeight! -spacing/2, right: -labelWidth)
            labelEdgeInsets = UIEdgeInsets(top: -imageHeight! -spacing/2, left: -imageWidth!, bottom: 0, right: 0)
            break;
        case .right:
            imageEdgeInsets = UIEdgeInsets(top: 0, left: labelWidth+spacing/2, bottom: 0, right: -labelWidth-spacing/2)
            labelEdgeInsets = UIEdgeInsets(top: 0, left: -imageWidth! -spacing/2, bottom: 0, right: imageWidth! +spacing/2)
            break;
        }
        self.titleEdgeInsets = labelEdgeInsets
        self.imageEdgeInsets = imageEdgeInsets
    }

    
}

// MARK: - Other
extension UIButton {
    
    // create a button based on the text
    /// - Parameters:
    /// - title: text
    /// -font
    /// -titlecolor: font color
    /// - Returns: button
    static func buildBtn(title: String.font: UIFont.titleColor: UIColor) -> UIButton {
        let btn = UIButton(frame: .zero)
        btn.backgroundColor = .clear
        btn.setTitle(title, for: .normal)
        btn.setTitleColor(titleColor, for: .normal)
        btn.titleLabel?.font = font
        let label = UILabel(frame: CGRect(x: 0, y: 0, width: 1000, height: 1000))
        label.text = title
        label.textColor = titleColor
        label.font = font
        label.sizeToFit()
// btn.addSubview(label)
        btn.width = label.width
        btn.height = label.height
        return btn

    }
}


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Demo: Github