CallRollTool.swift

import Foundation

class CallRollTool {
    static private var outMark = 0
    static private var inMark = 0
    
    static func call(interval: TimeInterval = 0.5, _ callBack:@escaping (()->())){
        outMark += 1
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + interval) {
            inMark += 1
            if outMark == inMark{
                inMark = 0
                outMark = 0
                callBack()
            }
        }
    }
}