Ios 如何使用导航按钮在swift 5中显示间隙广告

我正在创建一个带有ViewController的Ann应用程序，该应用程序有三个按钮，可以指向其他三个ViewController

我想我的间隙广告显示时，用户点击按钮。当广告结束时，视图控制器出现，当用户关闭视图控制器并转到根视图控制器并尝试打开另一个视图控制器时，广告出现，然后是视图控制器

import UIKit
import AVKit
import GoogleMobileAds



class ViewController: UIViewController {

    private var interstitialad : GADInterstitial!
    
      
    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.interstitialad = createAd()
            
    }
    @IBAction func news(_ sender: Any) {
        
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)
        }
      
    }
    
    @IBAction func table(_ sender: Any) {
                
                
                
                
                
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)
        }

    }
    @IBAction func channels(_ sender: Any) {
            
            
            
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)


        }
                  
    }
    private func createAd() ->GADInterstitial {
        
        let ad = GADInterstitial(adUnitID: "ca-app-pub-3940256099942544/4411468910")
        ad.delegate = self
        ad.load(GADRequest())
        return ad
    }
    
    
    
    
   

}

extension ViewController: GADInterstitialDelegate{
   
    func interstitialDidDismissScreen(_ ad: GADInterstitial) {

        interstitialad = createAd()
        
    }
    
    
}

下面的代码使广告出现，但完成后不要打开目标视图控制器

import UIKit
import AVKit
import GoogleMobileAds



class ViewController: UIViewController {

    private var interstitialad : GADInterstitial!
    
      
    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.interstitialad = createAd()
            
    }
    @IBAction func news(_ sender: Any) {
        
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)
        }
      
    }
    
    @IBAction func table(_ sender: Any) {
                
                
                
                
                
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)
        }

    }
    @IBAction func channels(_ sender: Any) {
            
            
            
        if interstitialad?.isReady == true {
            interstitialad?.present(fromRootViewController: self)


        }
                  
    }
    private func createAd() ->GADInterstitial {
        
        let ad = GADInterstitial(adUnitID: "ca-app-pub-3940256099942544/4411468910")
        ad.delegate = self
        ad.load(GADRequest())
        return ad
    }
    
    
    
    
   

}

extension ViewController: GADInterstitialDelegate{
   
    func interstitialDidDismissScreen(_ ad: GADInterstitial) {

        interstitialad = createAd()
        
    }
    
    
}

---

是否调用了

InterstitialIDDISMISSScreen

函数？否，未调用该函数