如何显示UIAableViewController的UIActivityIndicatorView?
问题描述:
我是iOS开发的初学者,我有一个关于如何显示UIActivityIndicatorView的问题。如何显示UIAableViewController的UIActivityIndicatorView?
这是我的结构:
我有一个的UITabBarController为根VC。我有一个UITableViewController 在TableView内部,我做了一个REST请求(此时是一个假申请)。
我想要什么?
当我启动应用程序时,TableView被加载并且请购已完成。 请求被创建时,我想显示UIActivityIndicatorView。
我的问题是显示此ActivityIndicatorView :(
我的代码
MainViewController(根VC)
import UIKit
class MainViewController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
setupTabBarItems()
}
private func setupTabBarItems() {
let items: [String] = ["Home", "Carrinho", "Categorias", "Conta"]
let homeVC = HomeTableViewController()
let carrinhoVC = UIViewController()
let categoriasVC = UIViewController()
let contaVC = UIViewController()
let tabBarList = [homeVC, carrinhoVC, categoriasVC, contaVC]
for i in 0..<4 {
tabBarList[i].tabBarItem = UITabBarItem(title: items[i], image: UIImage(named: items[i]), selectedImage: UIImage(named: items[i]))
}
viewControllers = tabBarList
}
}
HomeTableViewController(表视图)
import UIKit
class HomeTableViewController: UITableViewController {
let progressView: UIActivityIndicatorView = {
let p = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.whiteLarge)
p.backgroundColor = .black
p.translatesAutoresizingMaskIntoConstraints = false
p.startAnimating()
return p
}()
override func viewDidLoad() {
super.viewDidLoad()
// **the method is called here**
setupIndicatorView()
/* others methods */
}
private func setupIndicatorView() {
guard let window = UIApplication.shared.keyWindow else {return}
window.addSubview(progressView)
window.bringSubview(toFront: progressView)
// function to add constraints (is an extension of UIView)
window.constraint(pattern: "H:|[v0]|", views: progressView)
window.constraint(pattern: "V:|[v0]|", views: progressView)
}
/* other methods */
有什么建议吗?
答
直接添加progressView到的tableView:
private func setupIndicatorView() {
self.view.addSubview(progressView)
progressView.center = self.view.center // or instead use autolayout if you prefer it
}