UIBarButtonItem color setting in Swift-5.0

问题

I realised that the color-behaviour of my UIBarButtonItem's (left and right buttons) is not as desired.

If I press and hold the right UIBarButton (see video), then the color changes from light-yellow to gray'isch dark-yellow.

However, I would like a solution that keeps the same light-yellow color, no matter of any button selection, press-and-hold, etc. The button color should always stay the same light-yellow.

How can I achieve this ?

Here is the video done in Simulator: (you can clearly see that click-n-hold causes a color-change. what is the solution to keep the light-yellow color even when press-and-hold ??)

Here is the Code:

@IBOutlet weak var btnCancel: UIBarButtonItem!
@IBOutlet weak var btnApply: UIBarButtonItem!

override func viewDidLoad() {
    super.viewDidLoad()

    btnCancel.title = "Cancel".localized
    btnApply.title = "Apply".localized
    navigationItem.title = "Filter".localized

    let attributes: [NSAttributedString.Key : Any] = [ .font: UIFont(name: "Avenir-Heavy", size: 14)!, .foregroundColor: UIColor.yellow]
    navigationItem.rightBarButtonItem?.setTitleTextAttributes(attributes, for: .normal)
    navigationItem.rightBarButtonItem?.setTitleTextAttributes(attributes, for: .selected)
    navigationItem.rightBarButtonItem?.setTitleTextAttributes(attributes, for: .highlighted)
    navigationItem.rightBarButtonItem?.setTitleTextAttributes(attributes, for: .focused)
}

回答1:

Here is how you can achieve desired effect by wrapping a normal button as your barButton item.

    private let normalButton: UIButton = {
        let normalButton = UIButton()
        normalButton.frame = CGRect(x: 0, y: 0, width: 80, height: 30)
        normalButton.setTitle("Apply", for: .normal)
        normalButton.setTitleColor(.yellow, for: .normal)
        normalButton.isUserInteractionEnabled = true
        return normalButton
    }()

    private lazy var applyRightBarButtonItem: UIBarButtonItem = {
        // Wrap your button as UIBarButtonItem
        return UIBarButtonItem(customView: normalButton)
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        // Important for detecting taps
        normalButton.addTarget(self, action: #selector(normalButtonTapped), for: .touchUpInside)
        // Set your right bar button ( You can do the same for the left one)
        self.navigationItem.rightBarButtonItem = applyRightBarButtonItem

    }

    @objc private func normalButtonTapped() {
        // TODO: - Handle tap
        print("Button Tapped")
    }

回答2:

please try this approach:

// MARK:- Custom BarButton Appearance
private extension YourViewController {

    func setupBarButtonAppearance() {

        let color = UIColor.yellow
        let font = UIFont(name: "Avenir-Heavy", size: 14)!

        let customAppearance = UIBarButtonItem.appearance(whenContainedInInstancesOf: [YourViewController.self])

        customAppearance.setTitleTextAttributes([
        NSAttributedString.Key.foregroundColor : color,
        NSAttributedString.Key.font : font], for: .normal)

        customAppearance.setTitleTextAttributes([
        NSAttributedString.Key.foregroundColor : color,
        NSAttributedString.Key.font : font], for: .highlighted)
    }
}

simply call this method in your viewDidLoad()

来源：https://stackoverflow.com/questions/57957274/uibarbuttonitem-color-setting-in-swift-5-0

标签

swift

uibarbuttonitem

nsattributedstring

navigationitem