英文:

does not display a picture from the sf symbol directory

问题

我是一个初学者，在屏幕中央显示了一张图片（这是一个原型，用于检查是否一切正常），但是图片没有显示出来，我完全复制了名称，但没有效果。使用UIImage(systemName: "")也不起作用。但如果我使用来自Assets.xcassets的图片，一切都显示。

我的代码：

```swift
override func viewDidLoad() {
        super.viewDidLoad()
        let imageView = setupImageView(in: view)
        imageView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
        imageView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
    }
    
    
    func setupImageView(in view: UIView) -> UIImageView {
        let imageView = UIImageView()
        imageView.image =  UIImage(systemName: "pencil.and.outline")
        imageView.contentMode = .scaleAspectFill
        imageView.clipsToBounds = true
        imageView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(imageView)
        return imageView
    }

一个空屏幕与sfsymbol的调用，一个有狗的屏幕与资源一起显示。

我向具有聊天经验的程序员请教过，但没有人遇到过这样的问题。

<details>
<summary>英文:</summary>

I am a beginner and I have a picture displayed in the center of the screen (this is a prototype to check if everything works), but the picture is not displayed, I copied the name completely, but it does not work. does not work with UIImage(systemName: &quot;&quot;). but if i use picture from Assets.xcassets but everything shows.

my code:

override func viewDidLoad() {
super.viewDidLoad()
let imageView = setupImageView(in: view)
imageView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
imageView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
}

func setupImageView(in view: UIView) -> UIImageView {
    let imageView = UIImageView()
    imageView.image =  UIImage(systemName: "pencil.and.outline")
    imageView.contentMode = .scaleAspectFill
    imageView.clipsToBounds = true
    imageView.translatesAutoresizingMaskIntoConstraints = false
    view.addSubview(imageView)
    return imageView
}

an empty screen with a call is a call from sfsymbol, a screen with a dog is a screen with assests

[![](https://i.stack.imgur.com/KwALG.jpg)](https://i.stack.imgur.com/KwALG.jpg)

[![enter image description here][1]][1]

I asked programmers with experience in chat, but no one faced such a problem


  [1]: https://i.stack.imgur.com/JrjOA.png

</details>


# 答案1
**得分**: 0

根据您的截图和测试了您的代码，似乎 SF Symbol 确实被显示出来了。

只是颜色的问题。因为您在背景中使用了 `.link` 颜色，这恰好是 SF Symbols 的默认颜色，它会被正确添加为子视图，但您只是看不到它。

可能的解决方案：

1. 更改 SF Symbol 的颜色：

```swift
imageView.image = UIImage(systemName: "pencil.and.outline")?.withTintColor(.red, renderingMode: .alwaysOriginal)

2. 更改视图的背景颜色：

view.backgroundColor = .white

提示：如果您通过“调试视图层次结构”检查您的 UI，这是一个非常有用的工具，您应该能够看到它并轻松解决这类问题。

英文:

Judging by you screenshots and having tested your code, it seems that the SF Symbol is indeed displayed.

It's just a matter of colors. Since you're using .link color for the background, which is the same color of SF Symbols by default, it is correctly added as a subview but you just can't see it.

Possible solutions:

1. change SF Symbol color:

    imageView.image =  UIImage(systemName: "pencil.and.outline")?.withTintColor(.red, renderingMode: .alwaysOriginal)
   

2. change view's background color:

    view.backgroundColor = .white
   

Tip: if you inspect your UI through Debug View Hierarchy, a very useful tool, you should be able to see it and solve these kind of issues easily.