📅  最后修改于: 2022-03-11 14:59:09.077000             🧑  作者: Mango
self.view.addSubview(button)
button.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
button.topAnchor.constraint(equalTo: self.balanceLabel.bottomAnchor,constant:30),
button.centerXAnchor.constraint(equalTo: self.view.centerXAnchor),
])