我想在我的 View 顶部创建一个简单的栏,并排放置两个按钮,每个按钮占 50%。
我创建了这样的栏:
let topTabView = UIView()
topTabView.backgroundColor = UIColor.red
topTabView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(topTabView)
topTabView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
topTabView.topAnchor.constraint(equalTo: topLayoutGuide.bottomAnchor).isActive = true
topTabView.heightAnchor.constraint(equalToConstant: 60).isActive = true
topTabView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
这行得通。
然后我添加了我的两个按钮,我得到了所有的约束,除了我不确定如何让宽度 anchor 起作用,这样每个按钮都占据了 50% 的 View 。强>
let filterButton = UIButton()
filterButton.backgroundColor = UIColor.red
filterButton.setTitle("Filter", for: .normal)
filterButton.translatesAutoresizingMaskIntoConstraints = false
topTabView.addSubview(filterButton)
filterButton.leftAnchor.constraint(equalTo: topTabView.leftAnchor).isActive = true
filterButton.centerYAnchor.constraint(equalTo: topTabView.centerYAnchor).isActive = true
filterButton.heightAnchor.constraint(equalTo: topTabView.heightAnchor).isActive = true
// NOT SURE ABOUT THIS ONE
filterButton.widthAnchor.constraint(equalToConstant: 200).isActive = true
let mapButton = UIButton()
mapButton.backgroundColor = UIColor.red
mapButton.setTitle("Map", for: .normal)
mapButton.translatesAutoresizingMaskIntoConstraints = false
topTabView.addSubview(mapButton)
mapButton.rightAnchor.constraint(equalTo: topTabView.rightAnchor).isActive = true
mapButton.centerYAnchor.constraint(equalTo: topTabView.centerYAnchor).isActive = true
mapButton.heightAnchor.constraint(equalTo: topTabView.heightAnchor).isActive = true
// NOT SURE ABOUT THIS ONE
mapButton.widthAnchor.constraint(equalToConstant: 200).isActive = true
我试过类似的方法,但没有用:
mapButton.widthAnchor.constraint(equalToConstant: toTabView.frame.width / 2.0).isActive = true
任何帮助都会很棒!
最佳答案
so that each button takes up 50% of the view
这就是 multiplier
的用途。你没有使用它。使用它!
因此,您需要一个约束,其中按钮的宽度与父 View 的宽度相同,但其 multiplier
的值为 0.5
。
例子:
let b1 = UIButton()
b1.translatesAutoresizingMaskIntoConstraints = false
b1.backgroundColor = .green
b1.setTitle("Button1", for: .normal)
b1.setTitleColor(.black, for: .normal)
let b2 = UIButton()
b2.translatesAutoresizingMaskIntoConstraints = false
b2.backgroundColor = .yellow
b2.setTitle("Button2", for: .normal)
b2.setTitleColor(.black, for: .normal)
self.view.addSubview(b1)
self.view.addSubview(b2)
NSLayoutConstraint.activate([
b1.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 50),
b2.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 50),
b1.leadingAnchor.constraint(equalTo:self.view.leadingAnchor),
b2.leadingAnchor.constraint(equalTo:b1.trailingAnchor),
b1.widthAnchor.constraint(equalTo: self.view.widthAnchor, multiplier: 0.5),
b2.widthAnchor.constraint(equalTo: self.view.widthAnchor, multiplier: 0.5),
])
结果:
关于Swift 3 - 限制按钮宽度,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/41782539/