swift - 如何使单元格具有渐变背景？

Question

我在 View Controller 上插入了一个表格 View ，我想知道如何为表格 View 中的单元格提供渐变背景？我可以单独编辑每个单元格，为每个单元格赋予不同的颜色渐变背景吗？例如，每个单元格都在 trainingLevels 中的索引后面标记。数组，我怎么能在每个地方都有不同的颜色渐变背景？

这是我的代码:

import UIKit

 class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

var trainingLevels = ["Ball Handling", "Shooting", "Defense", "Advanced Drills", "Vertimax Drills", "Full Workouts", "BHB Products"]


@IBOutlet weak var tableView: TableView!


func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
    cell.backgroundColor = UIColor.clear
}

public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int
{

    return trainingLevels.count
}


public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
    let cell = UITableViewCell(style: UITableViewCellStyle.default, reuseIdentifier: "bell")
    cell.textLabel?.text = trainingLevels[indexPath.row]

    //cell details
    cell.backgroundColor = UIColor.black
    cell.textLabel?.textColor = UIColor.white



    return cell
}

override func viewDidLoad() {
    super.viewDidLoad()

    tableView.delegate = self
    tableView.dataSource = self

    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
}

Answer 1

您可以创建 UIView 的扩展:

extension UIView{
    func addGradientBackground(firstColor: UIColor, secondColor: UIColor){
        clipsToBounds = true
        let gradientLayer = CAGradientLayer()
        gradientLayer.colors = [firstColor.cgColor, secondColor.cgColor]
        gradientLayer.frame = self.bounds
        gradientLayer.startPoint = CGPoint(x: 0, y: 0)
        gradientLayer.endPoint = CGPoint(x: 0, y: 1)
        print(gradientLayer.frame)
        self.layer.insertSublayer(gradientLayer, at: 0)
    }
}

在你的细胞内简单地:

override func awakeFromNib() {
    super.awakeFromNib()
    self.addGradientBackground(firstColor: .green, secondColor: .blue)
}