How to implement interstitial Ads using AdMob in iOS with Swift?

Question

I'm implementing the interstitial Ads using the AdMob stuff but it is not displaying.

This is my class where I want to implement interstitial ads.

import UIKit
import GoogleMobileAds

class SearchNew: UIViewController{

    var interstitial: GADInterstitial!

    override func viewDidLoad() {
        super.viewDidLoad()

        self.interstitial = GADInterstitial(adUnitID: "ca-app-pub-3940256099942544/4411468910")

        let request = GADRequest()
        request.testDevices = ["2077ef9a63d2b398840261c8221a0c9b"]
        self.interstitial.loadRequest(request)

        self.showAd()
    }

    func showAd() {
        if self.interstitial.isReady {
            self.interstitial.presentFromRootViewController(self)
        }
    }

Answer 1

Add delegate function (GADInterstitialDelegate) for your class.

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate,  GADInterstitialDelegate {

    var mInterstitial: GADInterstitial!
    var gViewController: UIViewController?

Call loadRequest, it fires interstitialDidReceiveAd when ads ready to show

    func showAdmobInterstitial()
    {
            self.mInterstitial = GADInterstitial.init(adUnitID:kGoogleFullScreenAppUnitID )

            mInterstitial.delegate = self
            let Request  = GADRequest()
            Request.testDevices = ["2077ef9a63d2b398840261c8221a0c9b"]
            mInterstitial.loadRequest(Request)
    }

    func interstitialDidReceiveAd(ad: GADInterstitial!)
    {
        ad.presentFromRootViewController(self.gViewController)
    }

Call showAdmobInterstitial from any viewController

            let App = UIApplication.sharedApplication().delegate as! AppDelegate
            App.gViewController = self;
            App.showAdmobInterstitial()

Answer 2

In this way I did this admob Interstitial ads task

import UIKit
import GoogleMobileAds

//-------Interstitial adds--------
Step 1: You need to add this stuff in side your AppDelegate.swift file

@UIApplicationMain
Delegate: UIResponder, UIApplicationDelegate,GADInterstitialDelegate {

    var gViewController: UIViewController?

    var window: UIWindow?


 func showAdmobInterstitial()
    {
        let kGoogleFullScreenAppUnitID = "ca-app-pub-3940256099942544/4411468910";
        self.mInterstitial = GADInterstitial.init(adUnitID:kGoogleFullScreenAppUnitID )

        mInterstitial.delegate = self
        let Request  = GADRequest()
        Request.testDevices = ["2077ef9a63d2b398840261c8221a0c9b"]
        mInterstitial.loadRequest(Request)
    }

    func interstitialDidReceiveAd(ad: GADInterstitial!)
    {
        ad.presentFromRootViewController(self.gViewController)
    }
//-------------------------

Step 2: Now where ever or in any veiwController you want to show interstitial ads then add this stuff within that file.

let App = UIApplication.sharedApplication().delegate as! AppDelegate
            App.gViewController = self;
            App.showAdmobInterstitial()

By this way we can call now interstitial ads easily.