Wsrtjtyk

I am currently working on a swift animation. This animation gets triggered by an another function in unsteady time intervals (connected to a server). The animation takes 2 seconds to finish but its possible that it gets triggered before it has finished.
Thats why I was thinking about creating a waiting queue which stores the triggering events until the animation is completed and can be restarted. So on the one hand side I have to lock the animation function until its ready again and one the other I need some kind of storage for the incoming events in the meantime. I was already thinking about dispatch groups but couldnt figure out how I could use them.
I would be really happy about any input in which direction I could go to solve this problem.

Triggering function:

private func subscribeToNewBLock() {

        DispatchQueue.global(qos:.userInteractive).async {

            watchForNewBlock() {result in

                switch result {

                case .Failure:

                    return

                case .Success(let result):

                    //Animation function

                    self.moveBlocksDown(blockNumber: result)

                    //Recursive call to keep listening for new blocks

                    self.subscribeToNewBLock()

                }

            }

       }

}

You may try to make your animation queue as like below example

var results = [Int]()

var isAnimating = false



private func subscribeToNewBLock() {

    DispatchQueue.global(qos:.userInteractive).async {

        watchForNewBlock() {result in

            switch result {

            case .Failure:

                return

            case .Success(let result):



                //Call your UI operations in main thread

                DispatchQueue.main.async {



                    self.results.append(result)

                    //Animation function

                    self.moveBlocksDown()



                    //Recursive call to keep listening for new blocks

                    self.subscribeToNewBLock()

                }

            }

        }

    }

}



private func moveBlocksDown() {



    guard isAnimating == false && results.count > 0 else {



        return

    }



    self.moveBlocksDown(blockNumber: results.first!)



}



private func moveBlocksDown(blockNumber:Int){



    isAnimating = true



    UIView.animate(withDuration: 2.0, animations: {



        //Animation code goes here



    }) { (completed) in



        if completed{



            //Add follwing code in place of animation completed(May be in completion handler)

            self.isAnimating = false

            self.results = self.results.filter{$0 != blockNumber} //Remove already animated blockNumber

            self.moveBlocksDown() //Call moveBlocksDown function to check if anything pending in queue

        }

    }

}