屏幕上没有出现图像视图

Question

我正在尝试将背景图像添加到我的屏幕上并设置一些约束，但是不幸的是，该图像视图没有出现，我也不知道是什么原因。我检查了图像文件是否在项目文件夹中。

import UIKit

class ViewController: UIViewController {

    let backgroundImageView = UIImageView()

    override func viewDidLoad() {
       super.viewDidLoad()
       setBackground()
    }

    func setBackground() {
        view.addSubview(backgroundImageView)
        backgroundImageView.translatesAutoresizingMaskIntoConstraints = false
        backgroundImageView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
        backgroundImageView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
        backgroundImageView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
        backgroundImageView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
        backgroundImageView.image = UIImage(named: "background-test-image")
    }

}

Answer 1

将图像放入Assets.xcassets文件夹中