Saransh Agarwal Saransh Agarwal - 6 months ago 70
Android Question

Android Facebook integration login exception in setContentView

This is my MainActivity. The app is giving me a null pointer Exception at set content view and the app crashes please help.

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;

import com.facebook.CallbackManager;
import com.facebook.FacebookCallback;
import com.facebook.FacebookException;
import com.facebook.FacebookSdk;
import com.facebook.login.LoginResult;
import com.facebook.login.widget.LoginButton;

public class MainActivity extends AppCompatActivity {
private LoginButton loginButton;
private TextView info;
private CallbackManager callbackManager;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//here I get a nullpointerexception
FacebookSdk.sdkInitialize(getApplicationContext());
callbackManager = CallbackManager.Factory.create();
info = (TextView) findViewById(R.id.info);
loginButton = (LoginButton) findViewById(R.id.login_button);
loginButton.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
@Override
public void onSuccess(LoginResult loginResult) {
info.setText(
"User ID: "
+ loginResult.getAccessToken().getUserId()
+ "\n" +
"Auth Token: "
+ loginResult.getAccessToken().getToken()
);
}

@Override
public void onCancel() {

}

@Override
public void onError(FacebookException error) {
info.setText("Login attempt failed.");

}
});
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
callbackManager.onActivityResult(requestCode, resultCode, data);
}}


Above is my MainActivity. The app is giving me a null pointer Exception at set contentView The error is not resolving I have tried various ways

06-07 22:31:49.398 1020-1020/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.saranshagarwal.facebookintegration1, PID: 1020
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.saranshagarwal.facebookintegration1/com.example.saranshagarwal.facebookintegration1.MainActivity}: android.view.InflateException: Binary XML file line #16: Error inflating class com.facebook.login.widget.LoginButton
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5021)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:827)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:643)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.view.InflateException: Binary XML file line #16: Error inflating class com.facebook.login.widget.LoginButton
at android.view.LayoutInflater.createView(LayoutInflater.java:620)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:696)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
at com.example.saranshagarwal.facebookintegration1.MainActivity.onCreate(MainActivity.java:23)
at android.app.Activity.performCreate(Activity.java:5318)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1090)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 
at android.app.ActivityThread.access$800(ActivityThread.java:135) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:136) 
at android.app.ActivityThread.main(ActivityThread.java:5021) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:827) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:643) 
at dalvik.system.NativeStart.main(Native Method) 
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.constructNative(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at android.view.LayoutInflater.createView(LayoutInflater.java:594)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:696) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:755) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:492) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:397) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:353) 
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) 
at com.example.saranshagarwal.facebookintegration1.MainActivity.onCreate(MainActivity.java:23) 
at android.app.Activity.performCreate(Activity.java:5318) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1090) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 
at android.app.ActivityThread.access$800(ActivityThread.java:135) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:136) 
at android.app.ActivityThread.main(ActivityThread.java:5021) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:827) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:643) 
at dalvik.system.NativeStart.main(Native Method) 
Caused by: The SDK has not been initialized, make sure to call FacebookSdk.sdkInitialize() first.
at com.facebook.internal.Validate.sdkInitialized(Validate.java:145)
at com.facebook.AccessTokenTracker.<init>(AccessTokenTracker.java:55)
at com.facebook.login.widget.LoginButton$2.<init>(LoginButton.java:563)
at com.facebook.login.widget.LoginButton.configureButton(LoginButton.java:563)
at com.facebook.FacebookButtonBase.<init>(FacebookButtonBase.java:69)
at com.facebook.login.widget.LoginButton.<init>(LoginButton.java:201)
at java.lang.reflect.Constructor.constructNative(Native Method) 
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 
at android.view.LayoutInflater.createView(LayoutInflater.java:594) 
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:696) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:755) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:492) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:397) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:353) 
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:280) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140) 
at com.example.saranshagarwal.facebookintegration1.MainActivity.onCreate(MainActivity.java:23) 
at android.app.Activity.performCreate(Activity.java:5318) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1090) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 
at android.app.ActivityThread.access$800(ActivityThread.java:135) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:136) 
at android.app.ActivityThread.main(ActivityThread.java:5021) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:827) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:643) 
at dalvik.system.NativeStart.main(Native Method) 


This is my Log cat

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.saranshagarwal.facebookintegration1">

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

android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<meta-data
android:name="com.facebook.sdk.ApplicationId"
android:value="@string/app_id" />

<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.facebook.FacebookActivity"
android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
android:label="@string/app_name"
android:theme="@android:style/Theme.Translucent.NoTitleBar" />


</application>




This is my Manifest

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent"
android:padding="16dp"
>

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/info"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:textSize="18sp"
/>

<com.facebook.login.widget.LoginButton
android:id="@+id/login_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
/>




This is the activity_main.xml

Answer

Add this line just above setContentView not after

 FacebookSdk.sdkInitialize(getApplicationContext());

As you are using facebook sdk login button in activity_main xml and this xml you do set in setContentView and FacebookSdk is not initialize yet. So this gives you a null pointer exception.

Hope this will help you.