Swift 获取当前显示的ViewController

Swift 获取当前显示的ViewController

class public func getCurrentVc() -> UIViewController{
    let rootVc = UIApplication.shared.keyWindow?.rootViewController
    let currentVc =getCurrentVcFrom(rootVc!)
    return currentVc
   }

class private func getCurrentVcFrom(_ rootVc:UIViewController) -> UIViewController{
  var currentVc:UIViewController
  var rootCtr = rootVc
  if(rootCtr.presentedViewController != nil) {
    rootCtr = rootVc.presentedViewController!
  }
  if rootVc.isKind(of:UITabBarController.classForCoder()) {
    currentVc = getCurrentVcFrom((rootVc as! UITabBarController).selectedViewController!)
  }else if rootVc.isKind(of:UINavigationController.classForCoder()){
    currentVc = getCurrentVcFrom((rootVc as! UINavigationController).visibleViewController!)
  }else{
    currentVc = rootCtr
  }
  return currentVc
}