Firebase.java

1. //Internet Permission : -

    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

2. //Dependencies : -

    //Admob Ads SDK
    implementation 'com.google.android.gms:play-services-ads:21.3.0'
    //firebase SDk real-time
    implementation 'com.google.firebase:firebase-database:20.1.0'
    
    
3. //Meta Data : -

        <meta-data
            android:name="com.google.android.gms.ads.APPLICATION_ID"
            android:value="ca-app-pub-3940256099942544~3347511713"/>
    

4. //Sting File : -

    <string name="test_device_id">device_id</string>
    <!--   Admob App ID-->
    <string name="admob_APP_ID">ca-app-pub-3940256099942544~3347511713</string>
    <!-- Admob Ad Unit IDS Here -->
    <string name="admob_INTERSTITIAL_UNIT_ID">ca-app-pub-3940256099942544/1033173712</string>
    <string name="admob_BANNER_UNIT_ID">ca-app-pub-3940256099942544/6300978111</string>

5. //Variables : -

    private AdView mAdView;
    private InterstitialAd mInterstitialAd;

6. //All Methods : -


//Start Methods
private void initAdmobAd() {

        if (getString(R.string.test_device_id).length() > 12) {
            //Adding your device id -- to avoid invalid activity from your device
            List<String> testDeviceIds = Arrays.asList(getString(R.string.test_device_id));
            RequestConfiguration configuration =
                    new RequestConfiguration.Builder().setTestDeviceIds(testDeviceIds).build();
            MobileAds.setRequestConfiguration(configuration);
        }


        //Init Admob Ads
        MobileAds.initialize(this, new OnInitializationCompleteListener() {
            @Override
            public void onInitializationComplete(InitializationStatus initializationStatus) {
            }
        });

    }

    private void loadBannerAd() {

        mAdView = findViewById(R.id.adView);
        AdRequest adRequest = new AdRequest.Builder().build();
        mAdView.loadAd(adRequest);
    }

    private void loadFullscreenAd() {

        //Requesting for a fullscreen Ad
        AdRequest adRequest = new AdRequest.Builder().build();
        InterstitialAd.load(this, getString(R.string.admob_INTERSTITIAL_UNIT_ID), adRequest, new InterstitialAdLoadCallback() {
            @Override
            public void onAdLoaded(@NonNull InterstitialAd interstitialAd) {

                mInterstitialAd = interstitialAd;
                mInterstitialAd.setFullScreenContentCallback(new FullScreenContentCallback() {
                    @Override
                    public void onAdDismissedFullScreenContent() {
                    }
                }); // FullScreen Callback Ends here
            }

            @Override
            public void onAdFailedToLoad(@NonNull LoadAdError loadAdError) {
                // Handle the error
                mInterstitialAd = null;
            }
        });
    }

    private boolean isOnline() {

        ConnectivityManager cm = (ConnectivityManager) getSystemService(MainActivity.CONNECTIVITY_SERVICE);
        NetworkInfo netInfo = cm.getActiveNetworkInfo();
        return netInfo != null && netInfo.isConnectedOrConnecting();

    }

    private void firebase() {

        if (isOnline()) {
            FirebaseDatabase database = FirebaseDatabase.getInstance();
            DatabaseReference myRef = database.getReference("status");
            try {
                myRef.addValueEventListener(new ValueEventListener() {
                    @Override
                    public void onDataChange(@NonNull DataSnapshot snapshot) {
                        //Try firebase Start====================================================
                        try {
                            if (Boolean.TRUE.equals(snapshot.getValue(boolean.class))) {
                                initAdmobAd();
                                loadBannerAd();
                                loadFullscreenAd();
                            } else {
                                Log.e("error", "Status Error");
                            }
                        } catch (Exception e) {
                            Log.e("error", "Firebase Error");
                            e.printStackTrace();
                        }

                        //Try firebase End====================================================
                    }

                    @Override
                    public void onCancelled(@NonNull DatabaseError error) {
                    }
                });
            } catch (Exception e) {
                Log.e("error", "Firebase Error");
                e.printStackTrace();
            }
        }
    }

//End Methods

7. //Add to OnCreate : -

        //Call All Methods.
        firebase();

8. //Show Int-Ads : -

        if (mInterstitialAd != null) {
            mInterstitialAd.show(MainActivity.this);
            mInterstitialAd.setFullScreenContentCallback(new FullScreenContentCallback() {
                @Override
                public void onAdDismissedFullScreenContent() {
                    loadFullscreenAd();
                }
            });

        } else {
            Log.d("TAG", "The interstitial ad wasn't ready yet.");
        }
        
        //The End Here