Swift Dispatch Main sync messes UIView animation up

I am facing an issue where my UIView with a Lottie-Animation is not being correctly displayed. I am using a lot of Dispatch.main.async and I a pretty sure that is messing everything up.

1. User taps on a Button and instantly my UIVIew("coverView")+ Animation ("loadingAnimation") should be displayed (calling setupLoadingAnimation)

ScreenVideo

But it is not, it is only being displayed after a another function is finished.

How and where do I have to call animation.play() and view.isHidden = false so it is being displayed right after the button was tapped?

This is my structure:

@objc func addWishButtonTapped() {        print("tapped 1")      DispatchQueue.main.async { [weak self] in          guard let self = self else { return }            // ...          self.setUpLoadingAnimation()          // ...                    print("tapped 2")                    self.crawlWebsite {              print("tapped 3")              self.hideLoadingView()              print("tapped 4")          }        }  }  

The view is not being setup and it stops printing after print("tapped 2") and only print print(tapped 3"). That is when the view+ loadingAnimatino become visible.

Setup Loading Animation:

    //MARK: setupLoadingAnimation  func setUpLoadingAnimation(){            DispatchQueue.main.async { [weak self] in          guard let self = self else { return }          self.view.addSubview(self.coverView)          self.coverView.topAnchor.constraint(equalTo: self.wishView.topAnchor).isActive = true          self.coverView.leadingAnchor.constraint(equalTo: self.wishView.leadingAnchor).isActive = true          self.coverView.trailingAnchor.constraint(equalTo: self.wishView.trailingAnchor).isActive = true          self.coverView.bottomAnchor.constraint(equalTo: self.wishView.bottomAnchor).isActive = true                    self.loadingAnimation.contentMode = .scaleAspectFit          self.loadingAnimation.translatesAutoresizingMaskIntoConstraints = false          self.coverView.addSubview(self.loadingAnimation)                    self.loadingAnimation.centerXAnchor.constraint(equalTo: self.coverView.centerXAnchor).isActive = true          self.loadingAnimation.centerYAnchor.constraint(equalTo: self.coverView.centerYAnchor).isActive = true          self.loadingAnimation.heightAnchor.constraint(equalToConstant: 100).isActive = true          self.loadingAnimation.widthAnchor.constraint(equalToConstant: 100).isActive = true          self.loadingAnimation.loopMode = .loop          self.loadingAnimation.play()      }        }  

crawlWebsite:

    //MARK: crawlWebsite  func crawlWebsite(finished: @escaping () -> Void){            var html: String?      guard let url = self.url else { return }      let directoryURL = url as NSURL      let urlString: String = directoryURL.absoluteString!       // save url to wish      self.wishView.link = urlString         DispatchQueue.main.async { [weak self] in          guard let self = self else { finished(); return }          html = self.getHTMLfromURL(url: url)          self.getContentFromHTML(html: html, url: url)          self.getOpenGraphData(urlString: urlString) {              finished()          }      }  }  

I know this is very messy so I hope everything is clear! Let me know if you have any questions! I am very stuck here...

https://stackoverflow.com/questions/65836254/swift-dispatch-main-sync-messes-uiview-animation-up January 22, 2021 at 05:50AM