ios - Swift - 如何正确使用 MBProgressHUD.h？

Question

我有一些功能，我想在它们工作时显示progreeeHUD

我想出了两个显示和隐藏hud的函数

 func showHud() {
    let hud = MBProgressHUD.showHUDAddedTo(self.view, animated: true)

和

func hideHud() {
    MBProgressHUD.hideAllHUDsForView(self.view, animated: true)

我试过这样做

viewDidLoad

showHud()

func1()
func2()
func3()
func4()

showHud()

但这不起作用，hud 没有显示

我也试过了

@IBAction func goToGame(sender: UIButton) {


    let progressHUD = MBProgressHUD.showHUDAddedTo(self.view, animated: true)
    progressHUD.labelText = "Loading..."

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0)) {

        self.JSONRequest()
        self.loadFromDb()
        self.checkForDupl()
        self.saveToDb()

        dispatch_async(dispatch_get_main_queue()) {
            progressHUD.hide(true)
            self.performSegueWithIdentifier("toGameSegue", sender: nil)

        }
    }

这里的问题是必须在“toGameSegue”之后显示的 viewController 不等待 JSONRequest 和后续操作的完成，因此应用程序崩溃，因为它没有所需的数据

Answer 1

无阻塞

试试这个可见:

let loadingNotification = MBProgressHUD.showHUDAddedTo(self.view, animated: true)
loadingNotification.mode = MBProgressHUDMode.Indeterminate
loadingNotification.labelText = "Loading"

关闭 ProgressHUD:

MBProgressHUD.hideAllHUDsForView(self.view, animated: true)

就您而言:

@IBAction func goToGame(sender: UIButton) {


    let progressHUD = MBProgressHUD.showHUDAddedTo(self.view, animated: true)
    progressHUD.labelText = "Loading..."

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0)) {

        self.JSONRequest()


        dispatch_async(dispatch_get_main_queue()) {

        }
 }

func JSONRequest()
{
        //write it to success block
           self.loadFromDb()
            self.checkForDupl()
            self.saveToDb()
             progressHUD. hide (true)
             self.performSegueWithIdentifier("toGameSegue", sender: nil)
}