Question

为UIButton添加自定义图片或背景很容易，但似乎没有以编程方式为UIButton设置以下默认iOS图标之一，我知道它可以应用于导航栏按钮，我不需要，我想将它应用于简单的UIButton，任何提示？

Answer 1

对于Swift 5，语法为：

button.setImage(UIImage(systemName: "search"), for: .normal)

您还可以通过添加SymbolConfiguration来设置图标的权重：

let boldConfig = UIImage.SymbolConfiguration(weight: .bold)
let boldSearch = UIImage(systemName: "search", withConfiguration: boldConfig)

button.setImage(boldSearch, for: .normal)

请参阅：Apple documentation以获取可用名称（API列），或转到InterfaceBuilder，选择UIButton，然后在“属性检查器”中选择“图像”，该图像将为您提供所有可用图标的列表。

Answer 2

import UIKit

extension UIImage {

    public convenience init?(_ systemItem: UIBarButtonItem.SystemItem) {

        guard let sysImage = UIImage.imageFrom(systemItem: systemItem)?.cgImage else {
            return nil
        }

        self.init(cgImage: sysImage)
    }

    private class func imageFrom(systemItem: UIBarButtonItem.SystemItem) -> UIImage? {

        let sysBarButtonItem = UIBarButtonItem(barButtonSystemItem: systemItem, target: nil, action: nil)

        //MARK:- Adding barButton into tool bar and rendering it.
        let toolBar = UIToolbar()
        toolBar.setItems([sysBarButtonItem], animated: false)
        toolBar.snapshotView(afterScreenUpdates: true)

        if  let buttonView = sysBarButtonItem.value(forKey: "view") as? UIView{
            for subView in buttonView.subviews {
                if subView is UIButton {
                    let button = subView as! UIButton
                    let image = button.imageView!.image!
                    return image
                }
            }
        }
        return nil
    }
}

这是我们如何使用它的示例：

 let button = UIButton() ;
 let systemImage = UIImage(systemItem: .trash) ;
 button.setImage(systemImage, for: .normal)

Answer 3

我找到了 2521 个系统图标，作为数值。

@available(iOS 13.0, *)
@objc public extension UIImage{

    var assetName: String? {
        guard let imageAsset = imageAsset else { return nil }
        return imageAsset.value(forKey:"assetName") as? String
    }

    static var square_and_arrow_up: UIImage? {
        return UIImage(systemName: "square.and.arrow.up")
    }
    static var square_and_arrow_up_fill: UIImage? {
        return UIImage(systemName: "square.and.arrow.up.fill")
    }
    static var square_and_arrow_down: UIImage? {
        return UIImage(systemName: "square.and.arrow.down")
    }
    ...

截图： github：link

Answer 4

现在您可以做

button.setImage(UIImage(.search), for: .normal)

Answer 5

来自Apple的文档：init(type:)

如何以编程方式为UIButton添加系统图标？

5 个答案: