Ios 透明渐变在UIView类中不起作用
我试图在Ios 透明渐变在UIView类中不起作用,ios,swift,uiview,Ios,Swift,Uiview,我试图在UIView类中为UIView添加一个透明渐变,但它不起作用 class RecipesDetailsView: UIView { override init(frame: CGRect) { super.init(frame: frame) layoutUI() } required init?(coder: NSCoder) { fatalError("init(coder:) has not been im
UIView
类中为UIView
添加一个透明渐变,但它不起作用
class RecipesDetailsView: UIView {
override init(frame: CGRect) {
super.init(frame: frame)
layoutUI()
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
lazy var containerView: UIView = {
let containerView = UIView()
containerView.backgroundColor = .white
let gradientMaskLayer = CAGradientLayer()
gradientMaskLayer.frame = containerView.bounds
gradientMaskLayer.colors = [UIColor.clear.cgColor, UIColor.white.cgColor]
gradientMaskLayer.locations = [0, 1]
containerView.layer.mask = gradientMaskLayer
containerView.fadeView(style: .bottom, percentage: 0.5)
containerView.translatesAutoresizingMaskIntoConstraints = false
return containerView
}()
lazy var startCookingButton: UIButton = {
let startCookingButton = UIButton(type: .system)
startCookingButton.setTitle("Start cooking", for: .normal)
startCookingButton.setTitleColor(.white, for: .normal)
startCookingButton.backgroundColor = .CustomGreen()
startCookingButton.layer.cornerRadius = 8.0
startCookingButton.translatesAutoresizingMaskIntoConstraints = false
startCookingButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
return startCookingButton
}()
lazy var saveButton: UIButton = {
let saveButton = UIButton(type: .system)
saveButton.setTitleColor(.customDarkGray(), for: .normal)
saveButton.setTitle("Save", for: .normal)
saveButton.setImage(UIImage(systemName: "heart"), for: .normal)
saveButton.imageEdgeInsets = UIEdgeInsets(top: 0,left: -5,bottom: 0,right: 0)
saveButton.titleEdgeInsets = UIEdgeInsets(top: 0,left: 0,bottom: 0,right: -5)
saveButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
saveButton.tintColor = .customDarkGray()
saveButton.backgroundColor = .clear
saveButton.translatesAutoresizingMaskIntoConstraints = false
return saveButton
}()
func setupContainerViewConstraints() {
NSLayoutConstraint.activate([
containerView.bottomAnchor.constraint(equalTo: bottomAnchor),
containerView.leadingAnchor.constraint(equalTo: leadingAnchor),
containerView.trailingAnchor.constraint(equalTo: trailingAnchor),
containerView.heightAnchor.constraint(equalToConstant: frame.width / 5)
])
}
func setupStartCookingButton() {
NSLayoutConstraint.activate([
startCookingButton.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 16),
startCookingButton.bottomAnchor.constraint(equalTo: containerView.bottomAnchor, constant: -32),
startCookingButton.heightAnchor.constraint(equalToConstant: 55),
startCookingButton.widthAnchor.constraint(equalToConstant: frame.width * (2.5/4))
])
}
func setupSaveButtonConstraints() {
NSLayoutConstraint.activate([
saveButton.centerYAnchor.constraint(equalTo: startCookingButton.centerYAnchor),
saveButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
saveButton.heightAnchor.constraint(equalTo: startCookingButton.heightAnchor),
saveButton.widthAnchor.constraint(equalToConstant: frame.width * (1.2/4))
])
}
func addSubviews() {
addSubview(containerView)
containerView.addSubview(startCookingButton)
containerView.addSubview(saveButton)
}
func layoutUI() {
addSubviews()
setupContainerViewConstraints()
setupStartCookingButton()
setupSaveButtonConstraints()
}
}
我想要的是:
我从代码中获得的信息:
图层不会随视图“自动调整大小”,因此您需要保留渐变图层作为属性,并在视图布局更改时更新其边框
添加此属性:
private var gradientMaskLayer: CAGradientLayer!
然后,在lazy var containerView:UIView=
change中:
let gradientMaskLayer = CAGradientLayer()
致:
然后,添加此函数:
override func layoutSubviews() {
super.layoutSubviews()
gradientMaskLayer.frame = bounds
}
编辑 但是,这会将渐变遮罩应用于
containerView
及其子视图(按钮),这可能不是您想要的
因此,将addsubview()
func更改为:
func addSubviews() {
addSubview(containerView)
// add buttons to self, not to containerView
//containerView.addSubview(startCookingButton)
//containerView.addSubview(saveButton)
addSubview(startCookingButton)
addSubview(saveButton)
}
编辑2 下面是一个完整的实现,视图控制器的背景设置为红色:
class TestViewController: UIViewController {
var rv: RecipesDetailsView!
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .red
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
// with the way you are setting up the layout,
// we need to add the view here where we know the
// frame has been setup
if rv == nil {
let w = view.frame.width
let h = w / 5.0 * 2.0
let t = view.frame.height - h
rv = RecipesDetailsView(frame: CGRect(x: 0.0, y: t, width: w, height: h))
view.addSubview(rv)
}
}
}
class RecipesDetailsView: UIView {
// add this var / property
private var gradientMaskLayer: CAGradientLayer!
override init(frame: CGRect) {
super.init(frame: frame)
layoutUI()
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func layoutSubviews() {
super.layoutSubviews()
// layers do not follow frame changes, so update here
gradientMaskLayer.frame = bounds
}
lazy var containerView: UIView = {
let containerView = UIView()
containerView.backgroundColor = .white
gradientMaskLayer = CAGradientLayer()
gradientMaskLayer.frame = containerView.bounds
gradientMaskLayer.colors = [UIColor.clear.cgColor, UIColor.white.cgColor]
gradientMaskLayer.locations = [0, 1]
containerView.layer.mask = gradientMaskLayer
//containerView.fadeView(style: .bottom, percentage: 0.5)
containerView.translatesAutoresizingMaskIntoConstraints = false
return containerView
}()
lazy var startCookingButton: UIButton = {
let startCookingButton = UIButton(type: .system)
startCookingButton.setTitle("Start cooking", for: .normal)
startCookingButton.setTitleColor(.white, for: .normal)
//startCookingButton.backgroundColor = .CustomGreen()
startCookingButton.backgroundColor = .systemGreen
startCookingButton.layer.cornerRadius = 8.0
startCookingButton.translatesAutoresizingMaskIntoConstraints = false
startCookingButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
return startCookingButton
}()
lazy var saveButton: UIButton = {
let saveButton = UIButton(type: .system)
//saveButton.setTitleColor(.customDarkGray(), for: .normal)
saveButton.setTitleColor(.darkGray, for: .normal)
saveButton.setTitle("Save", for: .normal)
saveButton.setImage(UIImage(systemName: "heart"), for: .normal)
saveButton.imageEdgeInsets = UIEdgeInsets(top: 0,left: -5,bottom: 0,right: 0)
saveButton.titleEdgeInsets = UIEdgeInsets(top: 0,left: 0,bottom: 0,right: -5)
saveButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
//saveButton.tintColor = .customDarkGray()
saveButton.tintColor = .darkGray
saveButton.backgroundColor = .clear
saveButton.translatesAutoresizingMaskIntoConstraints = false
return saveButton
}()
func setupContainerViewConstraints() {
NSLayoutConstraint.activate([
containerView.bottomAnchor.constraint(equalTo: bottomAnchor),
containerView.leadingAnchor.constraint(equalTo: leadingAnchor),
containerView.trailingAnchor.constraint(equalTo: trailingAnchor),
containerView.heightAnchor.constraint(equalToConstant: frame.width / 5)
])
}
func setupStartCookingButton() {
NSLayoutConstraint.activate([
startCookingButton.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 16),
startCookingButton.bottomAnchor.constraint(equalTo: containerView.bottomAnchor, constant: -32),
startCookingButton.heightAnchor.constraint(equalToConstant: 55),
startCookingButton.widthAnchor.constraint(equalToConstant: frame.width * (2.5/4))
])
}
func setupSaveButtonConstraints() {
NSLayoutConstraint.activate([
saveButton.centerYAnchor.constraint(equalTo: startCookingButton.centerYAnchor),
saveButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
saveButton.heightAnchor.constraint(equalTo: startCookingButton.heightAnchor),
saveButton.widthAnchor.constraint(equalToConstant: frame.width * (1.2/4))
])
}
func addSubviews() {
addSubview(containerView)
// add buttons to self, not to containerView
//containerView.addSubview(startCookingButton)
//containerView.addSubview(saveButton)
addSubview(startCookingButton)
addSubview(saveButton)
}
func layoutUI() {
addSubviews()
setupContainerViewConstraints()
setupStartCookingButton()
setupSaveButtonConstraints()
}
}
结果:
我认为由于您使用的是自动布局,containerView.bounds为零。尝试添加一个框架来查看。@Joshua我尝试过,它会使按钮消失。你能添加你得到的和你想要得到的图像吗?@ValentinaKonatar我添加了我从代码中得到的和我想要得到的图像make@AhmedAbdElaziz-什么是
.fadeView(样式:。底部,百分比:0.5)
?编辑您的问题并包括您的.fadeView
扩展名。我评论fadeView
扩展名
class TestViewController: UIViewController {
var rv: RecipesDetailsView!
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .red
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
// with the way you are setting up the layout,
// we need to add the view here where we know the
// frame has been setup
if rv == nil {
let w = view.frame.width
let h = w / 5.0 * 2.0
let t = view.frame.height - h
rv = RecipesDetailsView(frame: CGRect(x: 0.0, y: t, width: w, height: h))
view.addSubview(rv)
}
}
}
class RecipesDetailsView: UIView {
// add this var / property
private var gradientMaskLayer: CAGradientLayer!
override init(frame: CGRect) {
super.init(frame: frame)
layoutUI()
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func layoutSubviews() {
super.layoutSubviews()
// layers do not follow frame changes, so update here
gradientMaskLayer.frame = bounds
}
lazy var containerView: UIView = {
let containerView = UIView()
containerView.backgroundColor = .white
gradientMaskLayer = CAGradientLayer()
gradientMaskLayer.frame = containerView.bounds
gradientMaskLayer.colors = [UIColor.clear.cgColor, UIColor.white.cgColor]
gradientMaskLayer.locations = [0, 1]
containerView.layer.mask = gradientMaskLayer
//containerView.fadeView(style: .bottom, percentage: 0.5)
containerView.translatesAutoresizingMaskIntoConstraints = false
return containerView
}()
lazy var startCookingButton: UIButton = {
let startCookingButton = UIButton(type: .system)
startCookingButton.setTitle("Start cooking", for: .normal)
startCookingButton.setTitleColor(.white, for: .normal)
//startCookingButton.backgroundColor = .CustomGreen()
startCookingButton.backgroundColor = .systemGreen
startCookingButton.layer.cornerRadius = 8.0
startCookingButton.translatesAutoresizingMaskIntoConstraints = false
startCookingButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
return startCookingButton
}()
lazy var saveButton: UIButton = {
let saveButton = UIButton(type: .system)
//saveButton.setTitleColor(.customDarkGray(), for: .normal)
saveButton.setTitleColor(.darkGray, for: .normal)
saveButton.setTitle("Save", for: .normal)
saveButton.setImage(UIImage(systemName: "heart"), for: .normal)
saveButton.imageEdgeInsets = UIEdgeInsets(top: 0,left: -5,bottom: 0,right: 0)
saveButton.titleEdgeInsets = UIEdgeInsets(top: 0,left: 0,bottom: 0,right: -5)
saveButton.titleLabel?.font = UIFont(name: "AvenirNext-Bold", size: 14)
//saveButton.tintColor = .customDarkGray()
saveButton.tintColor = .darkGray
saveButton.backgroundColor = .clear
saveButton.translatesAutoresizingMaskIntoConstraints = false
return saveButton
}()
func setupContainerViewConstraints() {
NSLayoutConstraint.activate([
containerView.bottomAnchor.constraint(equalTo: bottomAnchor),
containerView.leadingAnchor.constraint(equalTo: leadingAnchor),
containerView.trailingAnchor.constraint(equalTo: trailingAnchor),
containerView.heightAnchor.constraint(equalToConstant: frame.width / 5)
])
}
func setupStartCookingButton() {
NSLayoutConstraint.activate([
startCookingButton.leadingAnchor.constraint(equalTo: containerView.leadingAnchor, constant: 16),
startCookingButton.bottomAnchor.constraint(equalTo: containerView.bottomAnchor, constant: -32),
startCookingButton.heightAnchor.constraint(equalToConstant: 55),
startCookingButton.widthAnchor.constraint(equalToConstant: frame.width * (2.5/4))
])
}
func setupSaveButtonConstraints() {
NSLayoutConstraint.activate([
saveButton.centerYAnchor.constraint(equalTo: startCookingButton.centerYAnchor),
saveButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
saveButton.heightAnchor.constraint(equalTo: startCookingButton.heightAnchor),
saveButton.widthAnchor.constraint(equalToConstant: frame.width * (1.2/4))
])
}
func addSubviews() {
addSubview(containerView)
// add buttons to self, not to containerView
//containerView.addSubview(startCookingButton)
//containerView.addSubview(saveButton)
addSubview(startCookingButton)
addSubview(saveButton)
}
func layoutUI() {
addSubviews()
setupContainerViewConstraints()
setupStartCookingButton()
setupSaveButtonConstraints()
}
}