我想在按下后将 UIButton 的内容更改为 ActivityIndicator。
我知道按钮有一个 imageView 和一个 titleLabel,但我不知道如何在其中任何一个中放置事件指示器。
这就是我创建事件指标的方式:
let aiView = UIActivityIndicatorView(activityIndicatorStyle: .Gray)
aiView.startAnimating()
aiView.center = CGPointMake(0,0)
aiView.hidesWhenStopped = false
最佳答案
import UIKit
class LoadingButton: UIButton {
private var originalButtonText: String?
var activityIndicator: UIActivityIndicatorView!
func showLoading() {
originalButtonText = self.titleLabel?.text
self.setTitle("", for: .normal)
if (activityIndicator == nil) {
activityIndicator = createActivityIndicator()
}
showSpinning()
}
func hideLoading() {
self.setTitle(originalButtonText, for: .normal)
activityIndicator.stopAnimating()
}
private func createActivityIndicator() -> UIActivityIndicatorView {
let activityIndicator = UIActivityIndicatorView()
activityIndicator.hidesWhenStopped = true
activityIndicator.color = .lightGray
return activityIndicator
}
private func showSpinning() {
activityIndicator.translatesAutoresizingMaskIntoConstraints = false
self.addSubview(activityIndicator)
centerActivityIndicatorInButton()
activityIndicator.startAnimating()
}
private func centerActivityIndicatorInButton() {
let xCenterConstraint = NSLayoutConstraint(item: self, attribute: .centerX, relatedBy: .equal, toItem: activityIndicator, attribute: .centerX, multiplier: 1, constant: 0)
self.addConstraint(xCenterConstraint)
let yCenterConstraint = NSLayoutConstraint(item: self, attribute: .centerY, relatedBy: .equal, toItem: activityIndicator, attribute: .centerY, multiplier: 1, constant: 0)
self.addConstraint(yCenterConstraint)
}
}
关于ios - 在 UIButton 中显示事件指示器,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36539650/