Swift - 為什么我的 UIButton 需要雙擊才能處於選擇狀態？

Question

我有一個 UIButton，預期的行為是當它被點擊時，它應該具有藍色背景色，當未點擊時，它應該是白色。 但是，我總是必須在第一次嘗試時雙擊它才能被選中......這是為什么？

class CheckmarkCell: UITableViewCell {
    static let reuseIdentifier = String(describing: CheckmarkCell.self)

    @IBOutlet private weak var titleLabel: UILabel!
    @IBOutlet private weak var yesButton: UIButton!

    private weak var delegate: CheckmarkCellDelegate?
    private var value: Bool?

    public func configure(title: String, value: Bool?, delegate: CheckmarkCellDelegate? = nil) {
        self.titleLabel.text = title
        self.value = value
        self.delegate = delegate
        self.yesButton.layer.masksToBounds = true
        self.yesButton.layer.cornerRadius = self.yesButton.frame.width / 2
        self.yesButton.layer.borderWidth = 1.0
        self.yesButton.layer.borderColor = UIColor.NBABlue?.cgColor
        self.yesButton.backgroundColor = UIColor.white
            // This is the dot
        self.yesButton.tintColor = UIColor.clear

        // This block of code saves the values. If it is removed, when you scroll, values will all be deselected and false.
        switch self.value {
        case true:
            // This is the saved state
            self.yesButton.backgroundColor = UIColor.NBABlue
            self.yesButton.tintColor = UIColor.clear

            // Deselected, should e white.
        case false:
            self.yesButton.backgroundColor = UIColor.white
            self.yesButton.tintColor = UIColor.clear
        default:
            break
        }
    }

    @IBAction func buttonTapped(_ sender: UIButton) {
        if sender.isSelected {
            yesButton.isSelected = false
                // The selected state
            self.yesButton.backgroundColor = UIColor.NBABlue
            self.yesButton.tintColor = UIColor.clear
            if self.value == nil || self.value == false {
                self.value = true
                self.delegate?.checkmarkCell(self, selectedValue: self.value!)
            }
        } else {
            yesButton.isSelected = true
            self.yesButton.backgroundColor = UIColor.white
            self.yesButton.tintColor = UIColor.clear
            if self.value == nil || self.value == true {
                self.value = false
                self.delegate?.checkmarkCell(self, selectedValue: self.value!)
            }
        }
    }
}

Answer 1

單元格被重用在configure添加這個

self.yesButton.tintColor = UIColor.clear // below this
self.yesButton.isSelected = self.value

Answer 2

要刪除藍色背景，您必須從故事板中清除色調。

在節文件 IBAction 中寫下這一行。

sender.isSelected = !sender.isSelected