android | App keeps crashing when I add admob banner ad into it

Question

I've been facing this issue every time I tried implementing ads into a VPN I'm making. Every time I was able to fix something but this is just not working at all and I have no idea what to do to fix it. I've tried implementing ads over 6 times, and got the same response every time I launched the app.

A crash.

I'm pretty new to android dev and android studio so I expected this...

Log:

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.pronner.ragtagvpn, PID: 5295
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.pronner.ragtagvpn/com.pronner.ragtagvpn.view.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.ads.AdView.loadAd(com.google.android.gms.ads.AdRequest)' on a null object reference
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3676)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3813)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2308)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loopOnce(Looper.java:201)
        at android.os.Looper.loop(Looper.java:288)
        at android.app.ActivityThread.main(ActivityThread.java:7898)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)
     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.ads.AdView.loadAd(com.google.android.gms.ads.AdRequest)' on a null object reference
        at com.pronner.ragtagvpn.view.MainActivity.onCreate(MainActivity.java:62)
        at android.app.Activity.performCreate(Activity.java:8290)
        at android.app.Activity.performCreate(Activity.java:8269)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1384)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3657)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3813) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:101) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2308) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loopOnce(Looper.java:201) 
        at android.os.Looper.loop(Looper.java:288) 
        at android.app.ActivityThread.main(ActivityThread.java:7898) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

MainActivity.java OnCreate:

package com.pronner.ragtagvpn.view;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;

import androidx.annotation.NonNull;
import androidx.appcompat.app.ActionBarDrawerToggle;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.core.view.GravityCompat;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentTransaction;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.pronner.ragtagvpn.R;
import com.pronner.ragtagvpn.Utils;
import com.pronner.ragtagvpn.adapter.ServerListRVAdapter;
import com.pronner.ragtagvpn.interfaces.ChangeServer;
import com.pronner.ragtagvpn.interfaces.NavItemClickListener;
import com.pronner.ragtagvpn.model.Server;

import com.google.android.gms.ads.MobileAds;
import com.google.android.gms.ads.initialization.InitializationStatus;
import com.google.android.gms.ads.initialization.OnInitializationCompleteListener;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity implements NavItemClickListener {
    private FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
    private Fragment fragment;
    private RecyclerView serverListRv;
    private ArrayList<Server> serverLists;
    private ServerListRVAdapter serverListRVAdapter;
    private DrawerLayout drawer;
    private ChangeServer changeServer;

    public static final String TAG = "RagTagVPN";

    private AdView mAdView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

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

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


        // Initialize all variable
        initializeAll();

        ImageButton menuRight = findViewById(R.id.navbar_right);

        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        getSupportActionBar().setDisplayShowTitleEnabled(false);


        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);

        menuRight.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                closeDrawer();
            }
        });

        transaction.add(R.id.container, fragment);
        transaction.commit();

        // Server List recycler view initialize
        if (serverLists != null) {
            serverListRVAdapter = new ServerListRVAdapter(serverLists, this);
            serverListRv.setAdapter(serverListRVAdapter);
        }

    }

AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.pronner.ragtagvpn">
    <queries>

        <intent>
            <action android:name="android.intent.action.VIEW" />
            <data android:scheme="https" />
        </intent>
        <intent>
            <action android:name="android.intent.action.DIAL" />
            <data android:scheme="tel" />
        </intent>
        <intent>
            <action android:name="android.intent.action.SEND" />
            <data android:mimeType="*/*" />
        </intent>

    </queries>

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

    <application
        android:allowBackup="true"
        android:icon="@drawable/ragtag"
        android:label="RagTagVPN"
        android:extractNativeLibs="true"
        tools:replace="android:extractNativeLibs"
        android:roundIcon="@drawable/ragtag"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <activity android:name="com.pronner.ragtagvpn.view.MainActivity"
            android:exported="true">
            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <action android:name="com.example.app.START_BACKGROUND" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>
        </activity>

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

    <activity
        android:name="de.blinkt.openvpn.DisconnectVPNActivity"
        android:excludeFromRecents="true"
        android:noHistory="true"
        android:taskAffinity=".DisconnectVPN"
        android:theme="@style/blinkt.dialog" />

    <service
        android:name="de.blinkt.openvpn.core.OpenVPNService"
        android:permission="android.permission.BIND_VPN_SERVICE"
        android:exported="true">
        <intent-filter>
            <action android:name="android.net.VpnService" />
        </intent-filter>
    </service>

    </application>
</manifest>

Answer 1

Alright, so I was able to fix it. Basically, I was writing the MainActivity.java for the "fragment_main.xml" instead of the "activity_main.xml", Therefore it didn't work. Now, I implemented the adview on the activity_main.xml and it works.

Just keep in mind that everyone has different ways of solving this and your problem may be different, look into the simple things and try to solve the problem no matter how many times you fail.

And if your AdView is not being put correctly always use the translationX and translationY properties. If it appears on the center, use translationY to put it on the top/bottom.

Top: for example -150dp
Bottom: for example 150dp