【Swift Mac开发】继承NSButton并扩展功能（持续维护更新）

　　功能：

　　1、图片与文字的边距

　　2、移出移出更改背景颜色

　　3、快捷设置NSButton的字体颜色

　　4、快捷设置NSButton的背景颜色

//
//  BMButton.swift
//  BullMan
//
//  Created by Apple on 2021/5/11.
//

import Foundation
import Cocoa

class BMButton : NSButton {

    var oldBackgroundColor : NSColor!
    //MARK:按钮图片的内边距
    @IBInspectable var verticalImagePadding: CGFloat = 0
    @IBInspectable var horizontalImagePadding: CGFloat = 0
        
    override func draw(_ dirtyRect: NSRect) {
        
        let originalBounds = self.bounds
        defer { self.bounds = originalBounds }
        self.bounds = originalBounds.insetBy(
            dx: horizontalImagePadding,
            dy: verticalImagePadding
        )

        initButtonUiAction()

        let trackingArea = NSTrackingArea(
            rect: self.bounds,
            options: [.mouseEnteredAndExited, .activeAlways],
            owner: self,
            userInfo: nil)
        self.addTrackingArea(trackingArea)
        
        super.draw(dirtyRect)
    }
    
    func initButtonUiAction() {
        self.isBordered = false
        self.bezelStyle = .texturedSquare

    }
    
    override var intrinsicContentSize: NSSize {
        var size = super.intrinsicContentSize
        size.width += self.horizontalImagePadding
        size.height += self.verticalImagePadding
        return size;
    }
    
    //MARK:设置鼠标移入的背景颜色
    override func mouseEntered(with event: NSEvent) {
        let cell : NSButtonCell = self.cell! as! NSButtonCell
        cell.backgroundColor = NSColor.init(hexRGB: 0xf5f5f5)
    }

    //MARK:设置鼠标移出的被禁颜色
    override func mouseExited(with event: NSEvent) {
        let cell : NSButtonCell = self.cell as! NSButtonCell
        cell.backgroundColor = oldBackgroundColor
    }
}

class BMButtonCell : NSButtonCell {

    @IBInspectable var imagePaddingLeft   : CGFloat = 0
    @IBInspectable var imagePaddingTop    : CGFloat = 0
    @IBInspectable var textPaddingLeft   : CGFloat = 0
    @IBInspectable var textPaddingTop    : CGFloat = 0

    override func drawImage(_ image: NSImage, withFrame frame: NSRect, in controlView: NSView) {

        let newFrame = NSRect.init(
            origin: .init(x: frame.minX + imagePaddingLeft, y: frame.minY + imagePaddingTop),
            size: frame.size)

        super.drawImage(image, withFrame: newFrame, in: controlView)
    }

    override func drawTitle(_ title: NSAttributedString, withFrame frame: NSRect, in controlView: NSView) -> NSRect {
         let newFrame = NSRect.init(
                   origin: .init(x: frame.minX + textPaddingLeft, y: frame.minY + textPaddingTop),
                   size: frame.size)
        super.drawTitle(title, withFrame: newFrame, in: controlView)
        return newFrame
    }
    

}


extension BMButton {
    
    //MARK:设置按钮的字体颜色
    var titleTextColor : NSColor {
        
        get {
            let attrTitle = self.attributedTitle
            return attrTitle.attribute(NSAttributedString.Key.foregroundColor, at: 0, effectiveRange: nil) as! NSColor
        }
        
        set(newColor) {
            let attrTitle = NSMutableAttributedString(attributedString: self.attributedTitle)
            let titleRange = NSMakeRange(0, self.title.count)
            
            attrTitle.addAttributes([NSAttributedString.Key.foregroundColor: newColor], range: titleRange)
            self.attributedTitle = attrTitle
        }
    }
    
    //MARK:设置按钮的背景颜色
    var backgroundColor : NSColor {

        get {
            return oldBackgroundColor
        }
        
        set(newColor) {
            oldBackgroundColor = newColor
            self.wantsLayer = true
            self.layer?.backgroundColor = newColor.cgColor
        }
    }

}