1、UIButton贴近右边，高度固定，宽度跟随标题变化
class TestButton: UIButton {
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let btn = TestButton(type: .custom)
btn.setTitle("TestButton 1 2 3 sdasdad dadasd", for: .normal)
btn.setTitleColor(.black, for: .normal)
btn.layer.borderColor = UIColor.red.cgColor
btn.layer.borderWidth = 1
view.addSubview(btn)
btn.snp.makeConstraints { (make) in
make.centerY.equalToSuperview()
make.right.equalToSuperview().offset(-20)
make.height.equalTo(30)
}
}
}
效果：
2、限制宽度，多了就换行
class TestButton: UIButton {
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let btn = TestButton(type: .custom)
btn.setTitle("TestButton 1 2 3 sdasdad dadasd,TestButton 1 2 3 sdasdad dadasd,TestButton 1 2 3 sdasdad dadasd", for: .normal)
btn.setTitleColor(.black, for: .normal)
btn.titleLabel?.numberOfLines = 0
btn.layer.borderColor = UIColor.red.cgColor
btn.layer.borderWidth = 1
view.addSubview(btn)
btn.snp.makeConstraints { (make) in
make.centerY.equalToSuperview()
make.right.equalToSuperview().offset(-20)
// make.height.equalTo(30)
make.width.lessThanOrEqualTo(200)
}
}
}
效果：
明显，UIButton的框太小了，限制了titleLabel，现在想实现，button的高度和文字高度一样
修改如下
class TestButton: UIButton {
override var intrinsicContentSize: CGSize {
return titleLabel!.sizeThatFits(CGSize(width: titleLabel!.preferredMaxLayoutWidth, height: .greatestFiniteMagnitude))
}
override func layoutSubviews() {
titleLabel?.preferredMaxLayoutWidth = frame.size.width
super.layoutSubviews()
}
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let btn = TestButton(type: .custom)
btn.setTitle("TestButton 1 2 3 sdasdad dadasd,TestButton 1 2 3 sdasdad dadasd,TestButton 1 2 3 sdasdad dadasd", for: .normal)
btn.setTitleColor(.black, for: .normal)
btn.titleLabel?.numberOfLines = 0
btn.layer.borderColor = UIColor.red.cgColor
btn.layer.borderWidth = 1
view.addSubview(btn)
btn.snp.makeConstraints { (make) in
make.centerY.equalToSuperview()
make.right.equalToSuperview().offset(-20)
// make.height.equalTo(30)
make.width.lessThanOrEqualTo(200)
}
}
}
效果：
总结：
Autolayout和intrinsicContentSize有关，UIButton的intrinsicContentSize默认和标题长短没有关系，和UILabel不一样
原文：https://www.cnblogs.com/doudouyoutang/p/11815787.html