Android in-app purchase billing client crashes on build

Question

I am new to Android in-app purchases. I have followed the official documentation and I can't go beyond building the BillingClient as app crashes when it tries to build the BillingClient. Any help or any reference to a android in-app purchases in Java is much appreciated. My MainActivity.java codes is as follows:

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.webkit.WebSettings;
import android.webkit.WebView;

import com.android.billingclient.api.BillingClient;
import com.android.billingclient.api.BillingClientStateListener;
import com.android.billingclient.api.BillingResult;
import com.android.billingclient.api.Purchase;
import com.android.billingclient.api.PurchasesUpdatedListener;
import java.util.List;

public class MainActivity extends AppCompatActivity{

    private PurchasesUpdatedListener purchaseUpdateListener = new PurchasesUpdatedListener() {
        @Override
        public void onPurchasesUpdated(BillingResult billingResult, List<Purchase> purchases) {
            // To be implemented in a later section.
        }
    };


    private BillingClient billingClient = BillingClient.newBuilder(MainActivity.this)
            .setListener(purchaseUpdateListener)
            .enablePendingPurchases()
            .build();


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

}

Crash Log is as follows:

2020-07-07 01:19:40.667 27956-27956/? E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.js.bs, PID: 27956
    java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.js.bs/com.js.bs.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3272)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3500)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2049)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:223)
        at android.app.ActivityThread.main(ActivityThread.java:7523)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)
     Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
        at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:122)
        at com.android.billingclient.api.BillingClientImpl.initialize(com.android.billingclient:billing@@3.0.0:26)
        at com.android.billingclient.api.BillingClientImpl.<init>(com.android.billingclient:billing@@3.0.0:13)
        at com.android.billingclient.api.BillingClientImpl.<init>(com.android.billingclient:billing@@3.0.0:1)
        at com.android.billingclient.api.BillingClient$Builder.build(com.android.billingclient:billing@@3.0.0:14)
        at com.js.bs.MainActivity.<init>(MainActivity.java:31)
        at java.lang.Class.newInstance(Native Method)
        at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:95)
        at androidx.core.app.CoreComponentFactory.instantiateActivity(CoreComponentFactory.java:41)
        at android.app.Instrumentation.newActivity(Instrumentation.java:1253)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3260)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3500) 
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2049) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:223) 
        at android.app.ActivityThread.main(ActivityThread.java:7523) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941) 
2020-07-07 01:19:41.044 27956-27956/? I/Process: Sending signal. PID: 27956 SIG: 9

Hi Shalu I have added the crash log to the question thank you — jkndmiththinda, Jul 06 '20 at 15:27

score 4 · Accepted Answer · answered Jul 06 '20 at 15:59

4

Please change the billingClient object creation as below. While creating this object from outside the context may be null, so crashing. Move the object creation to onCreate() method of the activity.

    private BillingClient billingClient;

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

        billingClient = BillingClient.newBuilder(this)
            .setListener(purchaseUpdateListener)
            .enablePendingPurchases()
            .build();
    }

answered Jul 06 '20 at 15:59

Shalu T D

3,921
2
26
37

Thank you very much Shalu it worked :) Do you know any java examples of implementing android in-app purchase? – jkndmiththinda Jul 07 '20 at 08:31
1

Please accept as an answer, then it will be helpful for other users in this community. Sorry no example with me. If I found it, I will let you know. Please check https://developer.android.com/google/play/billing/integrate – Shalu T D Jul 07 '20 at 08:32

Android in-app purchase billing client crashes on build

1 Answers1

Linked